Re: [time-nuts] 10MHz Rubidium reference source for frequency counter
John wrote: It seems to me that it's just a case of expecting too much from a counter. Possibly, but a well-tuned 5370B can get to the low e-12's at 1-10 seconds. It has better one-shot resolution than the Pendulum, but not by a factor of 10. So, I'd have thought the Pendulum would at least get to the mid e-11's if the time base was up to it. To get the best performance from a counter, you need to set up the trigger thresholds well away from ground as Charles says. Also consider taking TI readings rather than frequency readings. Frequency readings are OK for initial setup and basic ADEV comparisons but they won't generally yield the best ADEV fidelity or the lowest possible measurement floor. Yes, using TI mode is essential for getting down to the counter's limits. Was Karen using frequency mode? I wasn't paying attention to that end of things. Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Here's another reference on driving 10-ish MHz square wave outputs via digital chips. A few years ago I hacked my HP Z3816 to covert its 4 - 19.6608 MHz square wave outputs to be 4 more 10 MHz outputs. In the process I reverse engineered some of what was there. I found each of these outputs came from one 74ACT040 inverter chip per output connector with several gates in parallel through 100 ohm resistors to give low impedance drive. Maybe all the parallel gates are overkill for most needs, but anyway, in the process I drew a schematic of the arrangement that was found there. You can find the schematic picture, labeled One of the 19.6608 MHz Outputs, near the middle of this page for the whole hacking project: http://www.xertech.net/Projects/Z3816/3816_mod.html Bob, I might add parenthetically, that while your responses always seem accurate and informative, many times they are presented in such a sketchy bullet-point way that only those who already understand what you are describing can accurately follow what you are trying to share. Maybe it is just my less-than-expert point of view, but I think a lot of your posts would benefit if you could give a bit more detail or maybe a link to some kind of example or explanation. I appreciate all you offer, it takes time to read and reply, but I think often you are preaching to the choir when a little more detail could reach the whole congregation. Change or not, please keep posting. Even the cryptic stuff contains meaning, perhaps a spur to dig deeper. Bruce, when posting here, used to baffle me too, but he often shared links to papers or schematics to aid in following the details of what he was describing. On 10/31/2014 5:02 PM, Bob Camp wrote: Hi A $0.15 each dual / quad / hex / octal buffer IC’s will get you 15 dbm per pair of gates. For under $10 in active parts you can have 30 or 40 outputs. I suspect that if you look inside the 3812 that’s exactly how they are generating the 10 MHz you are looking at. Bob On Oct 31, 2014, at 7:01 PM, Graham / KE9H ke9h.gra...@gmail.com wrote: Bill: On cable TV systems, 50 MHz to 500 (or higher) are the forward channel. (Head-end to client.) Below 30 MHz is the reverse channel, for data going from the client to the cable company. The band 30 to 50 is a cross over zone for the band splitting filters. It is designed to not amplify the forward direction below 50 MHz. --- Graham == On Fri, Oct 31, 2014 at 4:07 PM, Bill Riches bill.ric...@verizon.net wrote: Hi Bob, I connected 10 MHZ test jack output to a 15 db el-cheepo CATV amp and the output of that to a 4 way splitter. Splitter outputs went to 3336-3586 and counter. All seem to like the ref signal. Output of the amp takes makes the semi-square wave into a sick saw tooth. Amp is only rated from 50 to 500 mhz so strange things are happening with 10 MHZ input. Other CATV amps do have better low fx response - will play with that later. I have 10 mhz pulse from Lucent into trigger input of 465 scope and Thunderbolt gps output into vertical input of scope. Time base is set for .01 Usec per div. I notice that trace moves right to left then left to right about every 5 min or so. Moves about 3 div before changing directions. Why? Is the Lucent still making a list? It has only been on for a few hours. It takes about 10 min for GPS to go out from a cold start. (My Thunderbolt and RB do not change direction when using one as trigger and the other for vert input to scope) I ordered a USB to RS422 converter cable - will be here next week. What program is sort of working? Using Windoze 7 64bit and have an old XP machine available. Sure do appreciate all the info from our time nuts gurus! 73, Bill, WA2DVU Cape May, NJ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Bob et al, I don't understand the direction this question about the supercap has taken. It's connected to pin 1 of the GPS receiver. It looks to be a UT+, so that's the battery backup power. According to my UT+ manual the current draw on this pin is between 5uA (at 2.5V) and 100uA (at 5V)? How many hours will a .022F supercap keep at least 2.5V at that sort of discharge rate? Unless the cap has gone bad, it seems more likely that Bob's comment about it doing a fast survey and then doing a slower one in the background probably has merit. In fact, my unit goes through its survey mode pretty quickly on power up. So do those current/voltage figures imply several hours on the cap? Bob From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 9:22 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Arthur, Now that you mention it, yes, I do remember your post. Thanks for the reminder! Bob From: Arthur Dent golgarfrinc...@gmail.com To: time-nuts@febo.com Sent: Friday, October 31, 2014 9:20 PM Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net “…I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby….” Bob Camp kb8tq at n1k.org “I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present….” ++ Reposting what I had posted over a week ago, in case you missed it…. Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 “…Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all….” -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
We had something like that in school when I was a kid. (many years ago) I remember occasional click-click-click... as it got reset. mp...@clanbaker.org said: I am wondering what the easiest approach to this might be?I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Counting to 3600 won't work with leap seconds. :) I don't know the details of how a pulse sets the clock hands. I assume it can't set the time to a fraction of a pendulum swing so I don't see much use for something fancy like a GPSDO. But this is time-nuts, so anything is possible. I'd probably split the project into two parts. One is to keep good time on a computer, say something like a Raspberry Pi. You can use the net, or a low cost GPS unit, or something fancy like a GPSDO. The second part is how and when to generate the pulse. You can use GPIO pins, or modem control signals. You could use an old PC, but the payback due to reduced power will pay for a Raspberry Pi in a year or two depending on your power rates and how much power your old PC burns. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10MHz Rubidium reference source for frequency counter
csteinm...@yandex.com said: Yes, using TI mode is essential for getting down to the counter's limits. What's going on there? It's just a divide, right? Is the firmware not smart enough to do get enough precision? Do all counters have that problem? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP Z3816A GPS
Hello All... My HP Z3816A GPS box is in need of some TLC. Is there anyone on the list who works on these units? TIA 73 Don W4WJ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10MHz Rubidium reference source for frequency counter
It seems to me that it's just a case of expecting too much from a counter. Possibly, but a well-tuned 5370B can get to the low e-12's at 1-10 seconds. You can get down there with TI averaging, but the data you get is not ideal since the averaging process smooths out the very instabilities you're trying to characterize. (See Tom's page at http://www.leapsecond.com/pages/adev-avg/ for a good intuitive explanation.) Yes, using TI mode is essential for getting down to the counter's limits. Was Karen using frequency mode? I wasn't paying attention to that end of things. I'm not sure, but that's where most people start out. Going to TI mode may improve things a bit at the cost of a more complex, error-prone measurement process, but it still isn't going to measure a Morion at t=1s. -- john, KE5FX Miles Design LLC ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Setting Clocks in the Mid 1800's
On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid lmcda...@lmceng.com wrote: I gave a presentation on the Dent Dipleidoscope at the Harvard conference of the North American Sundial Society in 2013. If anyone is interested, I can provide a pdf of that presentation. The presentation includes history, detailed explanation of operation and lots of pictures of the construction of the dipleidoscope. (specifically on-list) Larry, I, for one, would appreciate your presentation. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
In message 54544287.3000...@pacific.net, Brooke Clarke writes: Hi Bob: I suspect that inside a screen room like that one, where I'm guessing the walls are iron/steel, there's not much of the Earth's mag field left to null. That would be very counter productive, because you would invariably get a very complex mag field which owuld be much harder to cancel out. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Selling time to the railroad
The physics department at the little Liberal Arts college I went to in Iowa, Grinnell college, used to sell time to the Rock Island Railroad. We had two excellent pendulum clocks that back when this was in action, were synchronized to zenith crossings of particular stars. This was a manual operation performed by undergraduates who were paid to be up at weird hours of the night. The time ticks from the clocks were transmitted to the Rock Island station in town electrically. I presume they distributed it by telegraph. hld -- Howard L. Davidson hl...@att.net ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Hi Bob, The traditional Hg ion clock with it's 40,5 GHz frequency is doable, but it would be interesting if it could be commercialized at a (time-nuts) friendly price. The modern optical clock got much easier to work with when the frequency comb was invented. The frequency comb and stable lasers is now commercialized, but not cheap, not cheap at all. Cheers, Magnus On 11/01/2014 02:27 AM, Bob Camp wrote: Hi Trapped ion clocks have been the “obvious successor” to a Cs tube for at least 30 years. There is a *lot* of very fancy work involved in getting from 10 MHz up to a very specific light wavelength with low ADEV and good phase noise….. Rocket science indeed. Time Nuts rocket science, but tough to do none the less. Bob On Oct 31, 2014, at 8:09 PM, paul swed paulsw...@gmail.com wrote: Humor aside. I did dig deeper. It seems that this technology could be commercialized in larger volumes and might land in the same cost as a good CS does today. Technically it looks reasonable. Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:45 PM, paul swed paulsw...@gmail.com wrote: Jim I am sorry to say thats the wrong clock picture. That picture is of 2 glass coffee tables and a toaster in between. I see you can order that art om ebay. Item number 142657nottoday3245 Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:36 PM, Jim Lux jim...@earthlink.net wrote: OK, I know you all want to go get one... http://discoverjpl.jpl.nasa.gov/posts/520 It's Bob Tjoelker in front of the Deep Space Atomic Clock (DSAC) being tested for magnetic field sensitivity. It's a trapped ion clock, 1 liter/1 kg, orders and orders of magnitude better than a USO in performance. (if it's in the building I think it's in, the rebar is made of non-magnetic stainless steel) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Arthur, Found your original picture/post. TNX! http://s906.photobucket.com/user/rjb1998/media/RFTG-uREF1photo1_zps87c505ca.jpg.html Would you share what you did for a 5 MHz buffer? Mike On 10/31/2014 10:20 PM, Arthur Dent wrote: Bob Stewart bob at evoria.net “…I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby….” Bob Camp kb8tq at n1k.org “I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present….” ++ Reposting what I had posted over a week ago, in case you missed it…. Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 “…Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all….” -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- 73, Mike, N1JEZ A closed mouth gathers no feet ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Hi The “easy way” is probably to take a GPS module and get the time out of that. There’s not a big need for a GPSDO in this case. The modules cost $20 and run on very little power. Mate the module up with your processor du-jour and let it figure out when the top of the hour is. There are a *bunch* of $15 boards out there. No need for anything fancy. The advantage of having a bit of code is that it can *know* when you are at 12:00:00 rather than having to count 3600 seconds past the last reset. I would use a … relay… to drive the clock. That way everything is isolated from everything else. You also get a nice real sounding click when it fires. Total cost of everything $50. Total time to get it all done….. I would take the clock to a “clock guy” to make sure it’s up to running this way. It would be a shame to fire things up and find that there is a problem with the clock. Even worse if you break something in the clock. — Totally off topic … we had a similar system in 8th grade. For some odd reason the reset didn’t work quite right. The clock tended to go nuts when the reset signal came through. Very distracting …. wonder why it did that …. Bob On Oct 31, 2014, at 9:29 PM, Mike Baker mp...@clanbaker.org wrote: Hello, Time-Nutters-- A friend has a vintage oak-cabinet pendulum movement clock made by The Self Winding Clock Company some time around 1903. The company was formed in 1886. By the early 1900's era, this clock was known for its relative accuracy. These clocks were pendulum controlled and powered by a rather small and frequently reset mainspring that was wound hourly by a set of 1.5 VDC dry-cell batteries. In 1890 (?) the Naval Observatory agreed to telegraph standard railway time.Western Union, which also owned the Self-Winding Clock Company, sold these clocks to the railroads and sent the hourly time coordinating signals around the country by telegraph. My friend has one of the railroad clocks that has the Western Union Telegraph hourly resetting option. My friend thought it would be an interesting juxtaposition of technology from two different eras by creating the momentary 3-volt resetting pulse every hour from a GPS disciplined oscillator / clock pulse. I am wondering what the easiest approach to this might be?I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Mike Baker *** ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi On Oct 31, 2014, at 10:20 PM, Arthur Dent golgarfrinc...@gmail.com wrote: Bob Stewart bob at evoria.net “…I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby….” Bob Camp kb8tq at n1k.org “I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present….” ++ Reposting what I had posted over a week ago, in case you missed it…. Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 “…Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) It’s the “see photo” part that I was having a hard time with. For what ever reason, the link in your original post did not work for me. Bob allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all….” -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Well Q = CV. If delta V = 1 and C = 0.022 then Q = 0.022. That’s 22 ma for 1 second or 22 ua for 1,000 seconds. At 5 ua you would get to about an hour. If the delta V is 2X that, the times would all double. If the current is 10X lower than the spec (it might be …) then you could get out to around a day. Bob On Nov 1, 2014, at 12:38 AM, Bob Stewart b...@evoria.net wrote: Hi Bob et al, I don't understand the direction this question about the supercap has taken. It's connected to pin 1 of the GPS receiver. It looks to be a UT+, so that's the battery backup power. According to my UT+ manual the current draw on this pin is between 5uA (at 2.5V) and 100uA (at 5V)? How many hours will a .022F supercap keep at least 2.5V at that sort of discharge rate? Unless the cap has gone bad, it seems more likely that Bob's comment about it doing a fast survey and then doing a slower one in the background probably has merit. In fact, my unit goes through its survey mode pretty quickly on power up. So do those current/voltage figures imply several hours on the cap? Bob From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 9:22 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Quick question - What about the other pins? Do they hook up in the same manner? If so, what happens to the odd pin? Bob On Oct 31, 2014, at 10:41 PM, Tom Miller tmiller11...@verizon.net wrote: Task 1 complete. Pin-1 - Pin-15 Pin-2 - Pin- 14 Pin-3 - Pin- 13 ... ... Pin-14 - Pin- 2 Pin-15 - Pin-1 Shell - Shell Regards, Tom - Original Message - From: Bob Camp kb...@n1k.org To: n1...@burlingtontelecom.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 8:27 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A,Z3811A, Z3812A GPSDO system Hi I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present. Yes that seems like it violates the spirit of redundancy. No I didn’t design it. Yes the guy who did spec it to work that way probably knew a whole lot more about exactly what they were after in the design. I suppose the first task would be to figure out if the jumper cable is a straight through or not…. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Self-setting / self-winding clock
Time-Nutters-- This particular 1903 Railroad self-setting/winding pendulum regulated clock needed only an hourly signal from a Western Union telegraph line to provide momentary closure of a relay contact. This supplied +3 VDC to rewind the spring and also reset the sweep seconds hand on the hour, every hour. From what I have learned about this, the resetting of the sweep seconds hand is mechanically coordinated to occur when the pendulum is at either end of its swing. It appears that is no way (that I know of) to guarantee that the telegraphed reset pulse would coincide with either end of the pendulum's travel. Apparently, the resetting of the sweep seconds hand will only occur within the time frame of any single pendulum swing. I suppose this means that the clock might be in error by as much as nearly one swing of the pendulum because it has to reach the end of its swing before the second hand is reset. Just guessing here, but I am thinking that all this clock needs is a 1-second long closure of a relay contact on the hour, every hour. I don't think that leap-seconds are an issue here as the clock can be manually adjusted for that whenever a leap second occurs. So-- it comes back to counting 3600 one-second pulses from a GPS clock...? Or am I missing something here...? Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock (Bob Camp)
I have Arduino and Parallax BS2 programs that check the time from a Motorola GPS card (UT) and then send out a pulse on an electronic relay once an hour. The pulse starts at 59:57 past the hour and ends at 59:59. The solenoid releases on each clock pretty close to the hour, and the clocks remain in synch indefinitely. The time is also displayed on a 2 line LCD in the GPS interface module. I've had this working in my house for years now, starting with WWV, WWVB, and now GPS. I'm happy to send the program to anyone interested. I've also used to drive slave clocks with a 1PPM pulse. Currently I have over 25 Self Winding clocks all synchronized. I have them wired serially in groups of 4 and send out 12v to each group. Works great. Mitch. -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of time-nuts-requ...@febo.com Sent: Saturday, November 01, 2014 5:51 AM To: time-nuts@febo.com Subject: time-nuts Digest, Vol 124, Issue 2 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. HP Z3816A GPS (w...@aol.com) 2. Re: 10MHz Rubidium reference source for frequency counter (John Miles) 3. Re: Setting Clocks in the Mid 1800's (Sanjeev Gupta) 4. Re: Mercury Ion Clock (Poul-Henning Kamp) 5. Selling time to the railroad (Howard Davidson) 6. Re: Mercury Ion Clock (Magnus Danielson) 7. Re: Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system (Mike Seguin) 8. Re: 1903 Railroad self-Winding / Self-setting Clock (Bob Camp) -- Message: 1 Date: Sat, 1 Nov 2014 02:15:52 -0400 From: w...@aol.com To: time-nuts@febo.com Subject: [time-nuts] HP Z3816A GPS Message-ID: 658d6.1dd91474.4185d...@aol.com Content-Type: text/plain; charset=US-ASCII Hello All... My HP Z3816A GPS box is in need of some TLC. Is there anyone on the list who works on these units? TIA 73 Don W4WJ -- Message: 2 Date: Sat, 1 Nov 2014 00:01:19 -0700 From: John Miles j...@miles.io To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: Re: [time-nuts] 10MHz Rubidium reference source for frequency counter Message-ID: 04e801cff5a1$a4d81c80$ee885580$@miles.io Content-Type: text/plain; charset=utf-8 It seems to me that it's just a case of expecting too much from a counter. Possibly, but a well-tuned 5370B can get to the low e-12's at 1-10 seconds. You can get down there with TI averaging, but the data you get is not ideal since the averaging process smooths out the very instabilities you're trying to characterize. (See Tom's page at http://www.leapsecond.com/pages/adev-avg/ for a good intuitive explanation.) Yes, using TI mode is essential for getting down to the counter's limits. Was Karen using frequency mode? I wasn't paying attention to that end of things. I'm not sure, but that's where most people start out. Going to TI mode may improve things a bit at the cost of a more complex, error-prone measurement process, but it still isn't going to measure a Morion at t=1s. -- john, KE5FX Miles Design LLC -- Message: 3 Date: Sat, 1 Nov 2014 15:14:51 +0800 From: Sanjeev Gupta gha...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Setting Clocks in the Mid 1800's Message-ID: cahzk5wdzpkrhgm1vswvpms-rwfwq0crfz_lxzrwxtgty5ok...@mail.gmail.com Content-Type: text/plain; charset=UTF-8 On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid lmcda...@lmceng.com wrote: I gave a presentation on the Dent Dipleidoscope at the Harvard conference of the North American Sundial Society in 2013. If anyone is interested, I can provide a pdf of that presentation. The presentation includes history, detailed explanation of operation and lots of pictures of the construction of the dipleidoscope. (specifically on-list) Larry, I, for one, would appreciate your presentation. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane -- Message: 4 Date: Sat, 01 Nov 2014 07:21:51 + From: Poul-Henning Kamp p...@phk.freebsd.dk To: Discussion of precise time and frequency measurement time-nuts@febo.com, Brooke Clarke bro...@pacific.net Subject: Re: [time-nuts] Mercury Ion Clock Message-ID: 2290.1414826...@critter.freebsd.dk Content-Type: text/plain; charset=us-ascii In message
Re: [time-nuts] Setting Clocks in the Mid 1800's
I would be quite interested in reading your presentation also. Thank you Paul WB8TSL On Sat, Nov 1, 2014 at 3:14 AM, Sanjeev Gupta gha...@gmail.com wrote: On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid lmcda...@lmceng.com wrote: I gave a presentation on the Dent Dipleidoscope at the Harvard conference of the North American Sundial Society in 2013. If anyone is interested, I can provide a pdf of that presentation. The presentation includes history, detailed explanation of operation and lots of pictures of the construction of the dipleidoscope. (specifically on-list) Larry, I, for one, would appreciate your presentation. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
I have the wall mounted version. I believe that the hour adjust solenoid took 100 volts or so. I will check my manual on the clock. At a minute before the top of the hour until a minute after the hour all traffic would stop on the WU lines and at the top of the hour a 100 v dc pulse came over the lines to reset the time. I believe it was in the 30s when WU decided they did not want to be in the time business and discontinued the service and said everyone could keep their clocks. I can imagine the next day clocks going home with office workers. WU charged a buck a month for the clock, service, and batteries. Many large offices had hundreds of these clocks. The book American Clocks -Volume 2 by Tran Duyly has everything you ever wanted to know about self winding clocks. 73, Bill, WA2DVU Cape May --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Measuring ADEV for a beginner
I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? Thanks Anthony ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all ? . ?? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
It certainly depends on your comfort with any particular technology. Be it discrete ICs or microprocessors what you ask for is indeed trivial to do. The hardest part may be building the pulse driver and thats not really hard. The telegraphs should have been a higher voltage to drive a 10-20 ma current across the coil. Leap second do not play into the operation as in 1900 there were not any. Humor aside Since the clock recals every hour (I suspect it runs slightly slow so that the hand advances to 0) Then a leap second washes out 1 hour after it happens. I would just grab one of the rediculously cheap neo GPS modules and an atmel tiny chip micro. But thats me. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 1:49 AM, Hal Murray hmur...@megapathdsl.net wrote: We had something like that in school when I was a kid. (many years ago) I remember occasional click-click-click... as it got reset. mp...@clanbaker.org said: I am wondering what the easiest approach to this might be?I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Counting to 3600 won't work with leap seconds. :) I don't know the details of how a pulse sets the clock hands. I assume it can't set the time to a fraction of a pendulum swing so I don't see much use for something fancy like a GPSDO. But this is time-nuts, so anything is possible. I'd probably split the project into two parts. One is to keep good time on a computer, say something like a Raspberry Pi. You can use the net, or a low cost GPS unit, or something fancy like a GPSDO. The second part is how and when to generate the pulse. You can use GPIO pins, or modem control signals. You could use an old PC, but the payback due to reduced power will pay for a Raspberry Pi in a year or two depending on your power rates and how much power your old PC burns. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Self-setting / self-winding clock
Mike I can't speak to the pendulum swing. I had seen clocks that did indeed have some form of mechanical lockout like you mention. So yes you are on target. Now we get to a bit of nitty gritty. When does the pulse arrive I suspect at 59:59. The goal is that the clock rolls up to 0 and is released by the pulse perhaps. So I mentioned that the pulse would be a higher voltage and 10-20 ma pulse. Thats telegraph behavior and if the telegraph coils not in the clock then as you say you are dealing with a 3V at some current pulse. One suggestion was a relay. Absolutely will work also solidstate relays they are cheap today and easily driven from a micro or traditional logic. I also suggested and agreed just buy a $21 maybe gps module as the source. They are really good cheap and very accurate. OK how about those pictures you mentioned? :-) Now as the saying goes Just do it. Regards Paul On Sat, Nov 1, 2014 at 11:06 AM, Mike Baker mp...@clanbaker.org wrote: Time-Nutters-- This particular 1903 Railroad self-setting/winding pendulum regulated clock needed only an hourly signal from a Western Union telegraph line to provide momentary closure of a relay contact. This supplied +3 VDC to rewind the spring and also reset the sweep seconds hand on the hour, every hour. From what I have learned about this, the resetting of the sweep seconds hand is mechanically coordinated to occur when the pendulum is at either end of its swing. It appears that is no way (that I know of) to guarantee that the telegraphed reset pulse would coincide with either end of the pendulum's travel. Apparently, the resetting of the sweep seconds hand will only occur within the time frame of any single pendulum swing. I suppose this means that the clock might be in error by as much as nearly one swing of the pendulum because it has to reach the end of its swing before the second hand is reset. Just guessing here, but I am thinking that all this clock needs is a 1-second long closure of a relay contact on the hour, every hour. I don't think that leap-seconds are an issue here as the clock can be manually adjusted for that whenever a leap second occurs. So-- it comes back to counting 3600 one-second pulses from a GPS clock...? Or am I missing something here...? Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Bill I responded to Mike there seems to be a number of threads running on this. So in fact you do have the telegraph coil in the clock. Makes sense to me. Thats why the 100 V they needed to drive 10-20 ma through the coil over distance and had to account for line loss. The boook you mention. Online? Regards Paul WB8TSL On Sat, Nov 1, 2014 at 8:00 AM, Bill Riches bill.ric...@verizon.net wrote: I have the wall mounted version. I believe that the hour adjust solenoid took 100 volts or so. I will check my manual on the clock. At a minute before the top of the hour until a minute after the hour all traffic would stop on the WU lines and at the top of the hour a 100 v dc pulse came over the lines to reset the time. I believe it was in the 30s when WU decided they did not want to be in the time business and discontinued the service and said everyone could keep their clocks. I can imagine the next day clocks going home with office workers. WU charged a buck a month for the clock, service, and batteries. Many large offices had hundreds of these clocks. The book American Clocks -Volume 2 by Tran Duyly has everything you ever wanted to know about self winding clocks. 73, Bill, WA2DVU Cape May --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
Usually phase detectors (we prefer to call them Time Interval Analysers) have data interfaces (RS232, GPIB, LAN). If you build your own then the interface is up to you: usually an RS232 is the best choice. The software to use: take a look at the Miles' TimeLab www.ke5fx.com/timelab/readme.htm or http://www.thegleam.com/ke5fx/. Of course, in case of the GPIB, you also will need an adapter: GPIB/USB or GPIB/LAN but the less expensive GPIB/RS232 maybe a good choice. On Sat, Nov 1, 2014 at 2:29 PM, Anthony Roby ar...@antamy.com wrote: I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? Thanks Anthony ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
what you want to measure is a time-series of either frequency data or phase data. the simplest possible case for a beginner would be to have two clocks with 1-PPS (one pulse per second) outputs, and connect one clock to the start-input and the other to the stop-input of a time-interval counter. If you measure phase, keep the time-interval number to a 5...6 digit number and you don't have to worry too much about the internal time-base of the counter. On Sat, Nov 1, 2014 at 3:29 PM, Anthony Roby ar...@antamy.com wrote: I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? Thanks Anthony ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Magnus, But for a time-nut how can price even enter into the conversation? Plus it only draws 10s of watts. A green super duper clock. Other comment I read is that there is no part that will wear out. Granted I suspect over many years something happens, but its not the typical CS depletion. I might speculate the glass windows fog or something or on earth the evacuated chamber ultimately leaks or the metal in the vacuum release stuff. No idea but pretty sure I won't be putting a watch on ebay any time soon. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 6:42 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: Hi Bob, The traditional Hg ion clock with it's 40,5 GHz frequency is doable, but it would be interesting if it could be commercialized at a (time-nuts) friendly price. The modern optical clock got much easier to work with when the frequency comb was invented. The frequency comb and stable lasers is now commercialized, but not cheap, not cheap at all. Cheers, Magnus On 11/01/2014 02:27 AM, Bob Camp wrote: Hi Trapped ion clocks have been the “obvious successor” to a Cs tube for at least 30 years. There is a *lot* of very fancy work involved in getting from 10 MHz up to a very specific light wavelength with low ADEV and good phase noise….. Rocket science indeed. Time Nuts rocket science, but tough to do none the less. Bob On Oct 31, 2014, at 8:09 PM, paul swed paulsw...@gmail.com wrote: Humor aside. I did dig deeper. It seems that this technology could be commercialized in larger volumes and might land in the same cost as a good CS does today. Technically it looks reasonable. Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:45 PM, paul swed paulsw...@gmail.com wrote: Jim I am sorry to say thats the wrong clock picture. That picture is of 2 glass coffee tables and a toaster in between. I see you can order that art om ebay. Item number 142657nottoday3245 Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:36 PM, Jim Lux jim...@earthlink.net wrote: OK, I know you all want to go get one... http://discoverjpl.jpl.nasa.gov/posts/520 It's Bob Tjoelker in front of the Deep Space Atomic Clock (DSAC) being tested for magnetic field sensitivity. It's a trapped ion clock, 1 liter/1 kg, orders and orders of magnitude better than a USO in performance. (if it's in the building I think it's in, the rebar is made of non-magnetic stainless steel) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] BBC TV program Click has material about GPS jamming and e Loran
Click is a short TV program produced by the BBC about tech related things. Anyway, the issue I see today (1/11/2014) http://www.bbc.co.uk/programmes/b04p21jv had a bit about GPS failure, GPS jamming, and use of eLORAN as a backup. *Hopefully* you can see it on the BBC iPlayer if interested, although I am not sure if those outside the UK can see it - you might need to use a proxy server in the UK, since I have no idea if they block access based on IP. Also more on the BBC in the last 24 hours or so about this. http://www.bbc.co.uk/news/science-environment-29758872 Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Paul, You mean, as all time-nuts already have redundant sites with at least 4 5071As with high-performance tubes, redundant cesium and rubidium fointains, set of active hydrogen masers, with everything in tight temperature, humidity and pressure control, UPS and diesel-engines, GPS/GLONASS/GALILEO receiver on temperature-stabilized piller and antenna, do TWSTFT to major labs... since money is no issue, right? The main problem with cesium tubes as I recall it is really the ionizer in the mass-spectrometer being poluted with cesium, this then creates bad S/N before running out of cesium in the oven. Yes, I agree it would be a great clock to have, but practical limits in cost is a challenge for most, so it would be interesting to look at it and ask how cheap it could be done. Cheers, Magnus On 11/01/2014 03:21 PM, paul swed wrote: Magnus, But for a time-nut how can price even enter into the conversation? Plus it only draws 10s of watts. A green super duper clock. Other comment I read is that there is no part that will wear out. Granted I suspect over many years something happens, but its not the typical CS depletion. I might speculate the glass windows fog or something or on earth the evacuated chamber ultimately leaks or the metal in the vacuum release stuff. No idea but pretty sure I won't be putting a watch on ebay any time soon. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 6:42 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: Hi Bob, The traditional Hg ion clock with it's 40,5 GHz frequency is doable, but it would be interesting if it could be commercialized at a (time-nuts) friendly price. The modern optical clock got much easier to work with when the frequency comb was invented. The frequency comb and stable lasers is now commercialized, but not cheap, not cheap at all. Cheers, Magnus On 11/01/2014 02:27 AM, Bob Camp wrote: Hi Trapped ion clocks have been the “obvious successor” to a Cs tube for at least 30 years. There is a *lot* of very fancy work involved in getting from 10 MHz up to a very specific light wavelength with low ADEV and good phase noise….. Rocket science indeed. Time Nuts rocket science, but tough to do none the less. Bob On Oct 31, 2014, at 8:09 PM, paul swed paulsw...@gmail.com wrote: Humor aside. I did dig deeper. It seems that this technology could be commercialized in larger volumes and might land in the same cost as a good CS does today. Technically it looks reasonable. Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:45 PM, paul swed paulsw...@gmail.com wrote: Jim I am sorry to say thats the wrong clock picture. That picture is of 2 glass coffee tables and a toaster in between. I see you can order that art om ebay. Item number 142657nottoday3245 Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:36 PM, Jim Lux jim...@earthlink.net wrote: OK, I know you all want to go get one... http://discoverjpl.jpl.nasa.gov/posts/520 It's Bob Tjoelker in front of the Deep Space Atomic Clock (DSAC) being tested for magnetic field sensitivity. It's a trapped ion clock, 1 liter/1 kg, orders and orders of magnitude better than a USO in performance. (if it's in the building I think it's in, the rebar is made of non-magnetic stainless steel) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Absolutely! but it's not just the price of the hardware. The clock has mercury in it. Horrors! So the paperwork involved with the EPA, OSHA, and who knows what other agency will cost more than the hardware. Best stick with a hydrogen clock, just stick an icepick in it when you want to get rid of it; pt and it's done. Safer than your old refrigerator. :-) seriously, tn's, see: http://www.microsemi.com/document-portal/doc_view/133441-rubidium-devices-material-safety-data-sheet Don paul swed Magnus, But for a time-nut how can price even enter into the conversation? Plus it only draws 10s of watts. A green super duper clock. Other comment I read is that there is no part that will wear out. Granted I suspect over many years something happens, but its not the typical CS depletion. I might speculate the glass windows fog or something or on earth the evacuated chamber ultimately leaks or the metal in the vacuum release stuff. No idea but pretty sure I won't be putting a watch on ebay any time soon. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 6:42 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: Hi Bob, The traditional Hg ion clock with it's 40,5 GHz frequency is doable, but it would be interesting if it could be commercialized at a (time-nuts) friendly price. The modern optical clock got much easier to work with when the frequency comb was invented. The frequency comb and stable lasers is now commercialized, but not cheap, not cheap at all. Cheers, Magnus On 11/01/2014 02:27 AM, Bob Camp wrote: Hi Trapped ion clocks have been the “obvious successor” to a Cs tube for at least 30 years. There is a *lot* of very fancy work involved in getting from 10 MHz up to a very specific light wavelength with low ADEV and good phase noise….. Rocket science indeed. Time Nuts rocket science, but tough to do none the less. Bob On Oct 31, 2014, at 8:09 PM, paul swed paulsw...@gmail.com wrote: Humor aside. I did dig deeper. It seems that this technology could be commercialized in larger volumes and might land in the same cost as a good CS does today. Technically it looks reasonable. Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:45 PM, paul swed paulsw...@gmail.com wrote: Jim I am sorry to say thats the wrong clock picture. That picture is of 2 glass coffee tables and a toaster in between. I see you can order that art om ebay. Item number 142657nottoday3245 Regards Paul WB8TSL On Fri, Oct 31, 2014 at 1:36 PM, Jim Lux jim...@earthlink.net wrote: OK, I know you all want to go get one... http://discoverjpl.jpl.nasa.gov/posts/520 It's Bob Tjoelker in front of the Deep Space Atomic Clock (DSAC) being tested for magnetic field sensitivity. It's a trapped ion clock, 1 liter/1 kg, orders and orders of magnitude better than a USO in performance. (if it's in the building I think it's in, the rebar is made of non-magnetic stainless steel) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- The power of accurate observation is commonly called cynicism by those who have not got it. -George Bernard Shaw Dr. Don Latham AJ7LL Six Mile Systems LLC 17850 Six Mile Road Huson, MT, 59846 mail: POBox 404 Frenchtown MT 59834-0404 VOX 406-626-4304 Skype: buffler2 www.lightningforensics.com www.sixmilesystems.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
On 11/1/14, 9:08 AM, Magnus Danielson wrote: Paul, You mean, as all time-nuts already have redundant sites with at least 4 5071As with high-performance tubes, redundant cesium and rubidium fointains, set of active hydrogen masers, with everything in tight temperature, humidity and pressure control, UPS and diesel-engines, GPS/GLONASS/GALILEO receiver on temperature-stabilized piller and antenna, do TWSTFT to major labs... since money is no issue, right? The main problem with cesium tubes as I recall it is really the ionizer in the mass-spectrometer being poluted with cesium, this then creates bad S/N before running out of cesium in the oven. Yes, I agree it would be a great clock to have, but practical limits in cost is a challenge for most, so it would be interesting to look at it and ask how cheap it could be done. Having been to a few of the design reviews and such for the DSAC, and before, when it was called the 1 liter atomic clock, etc. I think one could build one *if* you have a fairly wide collection of skills, and you weren't hung up on it being tiny and low power, and zero maintenance. For instance, building a perfectly sealed physics package that is space flight compatible is non-trivial. Most of us don't have e-beam welding equipment sitting around (nor does JPL.. we contract that kind of stuff out). As Prestage points out in the article below, they started looking at how they build long life Traveling Wave Tubes for space (another precision ion optics device), and having spent some time in various TWT factories over the past 15 years: there is a lot of art in the manufacturing process. http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41329/1/07-2003.pdf http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41395/1/08-0610.pdf However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] 1903 Railroad self-Winding / Self-setting Clock
The Western Union clocks used in broadcasting up through the middle 70's were designed to be corrected through one-second current pulses over a standard 60 mA teletype loop. The clocks were wired in series like the old series Christmas-tree bulbs. Internally, the clocks employed two 1-1/2 V dry cells to supply 3 VDC to the winding mechanism. This was activated whenever the clock spring ran down and was independent of the setting (correcting) signal. When winding, the clocks emitted a soft purr. The setting mechanism was arranged so that the second-hand was seized and forced to the 00 position when the clock pulse arrived at xx:59. It was released at xx:00 when the one-second pulse ended. I believe a clutch mechanism prevented this setting action from affecting the pendulum. As another writer mentioned, the clocks were ideally adjusted to operate a fraction of a second slow in an hour's time; thus the second-hand was pulled forward a bit rather then retarded. The lead pendulum was short and the mechanisms not very elegant; thus the clocks were not very accurate when operated without the setting signal. I believe there was also a mechanical gate that allowed the clock to be reset only when the second hand was close to the 00 position. My understanding was that master clocks were installed in Western Union offices in the major cities where time service was provided. These master clocks actually generated the one-second pulses from xx:59 to xx:00 on each hour. Once a day a correcting pulse was routed across the country from the Naval Observatory. This was sent over telegraph circuits that were used for other purposes, too. At the appropriate time a technician had to enable the path to the office master clock to allow it to be corrected. This was apparently a manual operation. In originating network broadcast programs, timing accuracy needs to be well within one-second as one second typically represents about three words of the broadcast opening. At one point the Western Union technicians went on strike forcing management personnel to take over technical operations. Soon after we began noticing the clock error steadily increase. Calling Western Union did not seem to help as it is possible the management personnel were not familiar with how to route the daily timing pulse to correct their office master clock. After a week or so, we were forced to construct a driver for the clocks based upon a crystal-controlled clock that was set from WWV. When Western Union indicated they were dropping clock service, we elaborated on this to a precision time-code generator with provision for arming so as to introduce leap-seconds when needed and to change from standard to daylight time on schedule. In broadcasting we used both digital and analog clocks. The digital clocks were used for starting network feeds, but were not very acceptable to announcers reading copy or talking up to a switching point. They strongly preferred the proportional indication of a clock hand as it is difficult to translate digital indications into time left when trying to concentrate on other matters. Bruce, KG6OJI ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
I've confirmed from the model number that the GPS module on these is indeed an Oncore UT+. There's a Synergy engineering note available regarding Oncore battery backup, and one place a copy can be found is here... http://f6fgz.free.fr/Fichiers/GPS/Backup_Battery_Considerations.pdf If so desired, it would be possible to retrospectively convert the UT+ on the Z3811A to take the usual rechargeable battery but the precautions mentioned in the engineering note would need to be implemented. I'm running file checks on my archives right now so can't confirm exactly what's involved, but I think there's one zero ohm SMD chip to be removed at least, and fitting a battery can of course bring its own issues. If anyone's interested, I've just uploaded some detailed photos of the of RFTG-U Ref-1 circuit board to Didier's manuals site. Probably far more detail there than even the nuttiest of us might consider to be sane or healthy but I've got it apart anyway so what the heck and they might come in very useful if it decides to self destruct whilst I'm poking it about on the bench:-) Regards Nigel GM8PZR In a message dated 01/11/2014 06:20:00 GMT Standard Time, b...@evoria.net writes: Hi Bob et al, I don't understand the direction this question about the supercap has taken. It's connected to pin 1 of the GPS receiver. It looks to be a UT+, so that's the battery backup power. According to my UT+ manual the current draw on this pin is between 5uA (at 2.5V) and 100uA (at 5V)? How many hours will a .022F supercap keep at least 2.5V at that sort of discharge rate? Unless the cap has gone bad, it seems more likely that Bob's comment about it doing a fast survey and then doing a slower one in the background probably has merit. In fact, my unit goes through its survey mode pretty quickly on power up. So do those current/voltage figures imply several hours on the cap? Bob From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 9:22 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Magnus I would say that yes I do have various backups and none as good as any of this discussion. Agreeing with Jim much of this appears to me to be semi-reasonable and in particular in a amateur lab environment. But I am afraid thats just about how far I am going to get on the project. Its right behind the H maser. Any day now. Recovering the Frankenstein CS was about my real limit. I haven't seen any tubes show up on ebay lately. :-) Such is life. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 12:49 PM, Jim Lux jim...@earthlink.net wrote: On 11/1/14, 9:08 AM, Magnus Danielson wrote: Paul, You mean, as all time-nuts already have redundant sites with at least 4 5071As with high-performance tubes, redundant cesium and rubidium fointains, set of active hydrogen masers, with everything in tight temperature, humidity and pressure control, UPS and diesel-engines, GPS/GLONASS/GALILEO receiver on temperature-stabilized piller and antenna, do TWSTFT to major labs... since money is no issue, right? The main problem with cesium tubes as I recall it is really the ionizer in the mass-spectrometer being poluted with cesium, this then creates bad S/N before running out of cesium in the oven. Yes, I agree it would be a great clock to have, but practical limits in cost is a challenge for most, so it would be interesting to look at it and ask how cheap it could be done. Having been to a few of the design reviews and such for the DSAC, and before, when it was called the 1 liter atomic clock, etc. I think one could build one *if* you have a fairly wide collection of skills, and you weren't hung up on it being tiny and low power, and zero maintenance. For instance, building a perfectly sealed physics package that is space flight compatible is non-trivial. Most of us don't have e-beam welding equipment sitting around (nor does JPL.. we contract that kind of stuff out). As Prestage points out in the article below, they started looking at how they build long life Traveling Wave Tubes for space (another precision ion optics device), and having spent some time in various TWT factories over the past 15 years: there is a lot of art in the manufacturing process. http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41329/1/07-2003.pdf http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41395/1/08-0610.pdf However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Jim, On 11/01/2014 05:49 PM, Jim Lux wrote: Having been to a few of the design reviews and such for the DSAC, and before, when it was called the 1 liter atomic clock, etc. I think one could build one *if* you have a fairly wide collection of skills, and you weren't hung up on it being tiny and low power, and zero maintenance. For instance, building a perfectly sealed physics package that is space flight compatible is non-trivial. Most of us don't have e-beam welding equipment sitting around (nor does JPL.. we contract that kind of stuff out). As Prestage points out in the article below, they started looking at how they build long life Traveling Wave Tubes for space (another precision ion optics device), and having spent some time in various TWT factories over the past 15 years: there is a lot of art in the manufacturing process. Ah, yes, *most* time-nuts is not aiming to shoot their clocks into deep space. We are satisfied to stay in geostationary orbit or lower ;-) http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41329/1/07-2003.pdf http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41395/1/08-0610.pdf However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. Yes. I guess a bit of baking out the build is also to be recommended. I guess most of us don't do vacuum in our labs, so there is a challenge in itself, as there is many beginners mistakes to be done there. The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) Have tou cared to get the right isotope or do you use the natural abundance spreading? Hg-199 has an abundance of 16,87%. The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) Ah yes. Got a NaI(Tl) scintilator with about 1 cm copper filter and a matching PMT. No amp thought, but then again, I do not know what I should measure with it. :) The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I was thinking the same, especially when consider optical clocks, then 40 GHz isn't as esoteric. Traditional cesiums and rubidiums use a pair of synthesized frequencies being then sent into a step-recover diode inside a tuned cavity which then does the mixing and selects the right combination. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. Would be a fun project to do, things to be learned. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Paul, The lack of hydrogen masers here is disturbing. So is better cesiums tanked up and fresh. Will see what I can do with what I got. Fixing up rubidiums and cesiums is currently how far this lab goes. Cheers, Magnus On 11/01/2014 06:23 PM, paul swed wrote: Magnus I would say that yes I do have various backups and none as good as any of this discussion. Agreeing with Jim much of this appears to me to be semi-reasonable and in particular in a amateur lab environment. But I am afraid thats just about how far I am going to get on the project. Its right behind the H maser. Any day now. Recovering the Frankenstein CS was about my real limit. I haven't seen any tubes show up on ebay lately. :-) Such is life. Regards Paul WB8TSL On Sat, Nov 1, 2014 at 12:49 PM, Jim Lux jim...@earthlink.net wrote: On 11/1/14, 9:08 AM, Magnus Danielson wrote: Paul, You mean, as all time-nuts already have redundant sites with at least 4 5071As with high-performance tubes, redundant cesium and rubidium fointains, set of active hydrogen masers, with everything in tight temperature, humidity and pressure control, UPS and diesel-engines, GPS/GLONASS/GALILEO receiver on temperature-stabilized piller and antenna, do TWSTFT to major labs... since money is no issue, right? The main problem with cesium tubes as I recall it is really the ionizer in the mass-spectrometer being poluted with cesium, this then creates bad S/N before running out of cesium in the oven. Yes, I agree it would be a great clock to have, but practical limits in cost is a challenge for most, so it would be interesting to look at it and ask how cheap it could be done. Having been to a few of the design reviews and such for the DSAC, and before, when it was called the 1 liter atomic clock, etc. I think one could build one *if* you have a fairly wide collection of skills, and you weren't hung up on it being tiny and low power, and zero maintenance. For instance, building a perfectly sealed physics package that is space flight compatible is non-trivial. Most of us don't have e-beam welding equipment sitting around (nor does JPL.. we contract that kind of stuff out). As Prestage points out in the article below, they started looking at how they build long life Traveling Wave Tubes for space (another precision ion optics device), and having spent some time in various TWT factories over the past 15 years: there is a lot of art in the manufacturing process. http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41329/1/07-2003.pdf http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/41395/1/08-0610.pdf However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] BBC TV program Click has material about GPS jammingand e Loran
The politics of this system are a bit dubious as are the claims on accuracy and freedon from jamming. But it does give us another off-air frequency standard. Alan G3NYK - Original Message - From: Dr. David Kirkby (Kirkby Microwave Ltd) drkir...@kirkbymicrowave.co.uk To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, November 01, 2014 3:07 PM Subject: [time-nuts] BBC TV program Click has material about GPS jammingand e Loran Click is a short TV program produced by the BBC about tech related things. Anyway, the issue I see today (1/11/2014) http://www.bbc.co.uk/programmes/b04p21jv had a bit about GPS failure, GPS jamming, and use of eLORAN as a backup. *Hopefully* you can see it on the BBC iPlayer if interested, although I am not sure if those outside the UK can see it - you might need to use a proxy server in the UK, since I have no idea if they block access based on IP. Also more on the BBC in the last 24 hours or so about this. http://www.bbc.co.uk/news/science-environment-29758872 Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
Anthony, On 11/01/2014 02:29 PM, Anthony Roby wrote: I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? The time-interval counter, such as HP5370 or SR620, get started (channel 1) by a reference clock, such as 1 PPS and is then stopped (channel 2) by signal under test. The counter is typically read out through GPIB, even if some counters have serial interface and maybe even USB or Ethernet for really new (or retro-fitted), and the recommended path is to get a GPIB to USB interface for instance. Then use John Miles TimeLab. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
On 11/1/14, 11:05 AM, Magnus Danielson wrote: Jim, However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. Yes. I guess a bit of baking out the build is also to be recommended. I guess most of us don't do vacuum in our labs, so there is a challenge in itself, as there is many beginners mistakes to be done there. I haven't done high vacuum in quite a few years, but it is fascinating and frustrating. These days, quite a bit of surplus gear is out there that does make life easier (e.g. turbo molecular pumps). A Hg Ion system isn't real huge, and doesn't have a big gas load, so a straightforward LN2 sorption pump would probably work as a batch mode(e.g. a bunch of the right material, plunged into a LN bath, and it the gas molecules just stick right to the material.. ) The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) Have tou cared to get the right isotope or do you use the natural abundance spreading? Hg-199 has an abundance of 16,87%. Interesting, I don't know if they go out and sort it, or if they set up the system so that it's basically a mass spec, and the wrong isotope doesn't make it through the quadrupole filter. I'll bet the latter. No matter how good your offline enrichment process is, there will always be some other stuff in there. For all I know, the actual ion trap is specific to the mass of the ions. The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) Ah yes. Got a NaI(Tl) scintilator with about 1 cm copper filter and a matching PMT. No amp thought, but then again, I do not know what I should measure with it. :) You can measure radiation from common household objects like bananas The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I was thinking the same, especially when consider optical clocks, then 40 GHz isn't as esoteric. Traditional cesiums and rubidiums use a pair of synthesized frequencies being then sent into a step-recover diode inside a tuned cavity which then does the mixing and selects the right combination. Same scheme might work here. Next time I'm talking to one of the DSAC folks, I'll ask how they do the synthesis chain. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. Would be a fun project to do, things to be learned. For when you get tired of counting femtoseconds.. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 5300B - HP 5308A Counter Time Base Question...
I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and needed to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Question...
Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?searchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom - Original Message - From: Burt I. Weiner b...@att.net To: time-nuts@febo.com Sent: Saturday, November 01, 2014 3:19 PM Subject: [time-nuts] HP 5300B - HP 5308A Counter Time Base Question... I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and needed to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Question...
Hi 4.5 Hz at 1 MHz is 4.5 ppm. That’s not out of the likely adjustment range on the basic crystal reference on a 5308. It’s probably a simple tweak to get it back into calibration. Bob On Nov 1, 2014, at 3:19 PM, Burt I. Weiner b...@att.net wrote: I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and needed to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Question...
The time basse oscillator is only a crystal around a logic gate; not exciting at all. The adjustment is on the 5300A unit. There is a hole in the rear panel of the case that allows adjustment. You are going to need a calibrated standard of some kind to calibrate it against. The manuals for both the 5300A and the 5309A are on the Keysight web site at http://www.keysight.com/main/facet.jspx?t=79910.g.3cc=USlc=engsm=gno=0 Cheers, Dave M Burt I. Weiner wrote: I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and needed to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
Hi The problem with setting up to measure any of this stuff is that it’s *very* dependent on the gear you have. There’s no big surprises below. It’s all “spend more money and have fewer things to figure out”. First you need a way to measure frequency out of your mixer (there are LOTS of ways …): If you grab a HP 5334 or HP 5335 to measure the frequency or time, you need to get the data out via GPIB. That’s a project by it’s self. If you grab a HP 53131 or CNT 90 to measure the frequency, you can use a serial port. One less project, way more money. If you grab a HP 5371, you just push a button and it pops up an ADEV plot. Less money than a 53131 (usually). It’s a bit limited on the range it will do ADEV over. If you grab a brand new Symmetricom Time Pod, you spend (gulp!!) a bit more. You can now do measurements easily over it’s frequency range. (If you can afford that option - can I come play at your house ?) Yes each of these is it’s own little rabbit hole to wander down and each has it’s own issues. Now you need a reference: GPSDO’s have their fans, they often have spurs and other “crud” on the output. They do have very good long term stability. OCXO’s are often pretty quiet and spur free. You need some way to calibrate them for really long term stuff. Rb’s come in a wide range of sizes and costs. Some are better than others. Their ADEV at 1 second often not as good as an OCXO. Cs standards and Hydrogen masers are (to me) in the same cost category as exotic test gear above. Fine for a company, not quite so easy for a basement guy. Again each of these is a bit of a project by it’s self. Often it turns into a “a couple of these and a couple of those” sort of solution. You only know something is right if you have another one to compare it to. Now you have some gear. Let’s ignore building the mixer board and assume that’s taken care of already. Now you need software: TimeLab is free and it will interface with many of the counters you might be using. It does all the math for you and puts up pretty plots. Highly recommended. There are other free software packages out there. Stable32 is another commonly used program. You need to get the data out of the counter before you can use it. There are other paid programs out there, Stable 32 is the best of the bunch. An Excel spread sheet is indeed another option. The ADEV math is *not* very complicated. Excel can do it all very easily. Getting data out of the counter could be a terminal program sort of thing (serial port) or something more complex (GPIB). In both cases there are a number of programs to pick between. With software, things like what computer and operating system you have will influence your choices. I’m a Mac person, but I also run Linux, Windows, FreeBSD and a few other things as needed. Most people have a favorite …. So, that’s the quick and dirty start to the “quick ADEV setup” process. There are: 4 counter like things X 4 reference ideas X (at least 4 mixer approaches) X (way more than) 4 software options = 256 paths you could follow. That’s quite a few, and many of them would be utter nonsense. Even pruning out the ones are unlikely to ever be followed, you still have lots. Here’s one: 1) Drive your “known good” reference OCXO into a Minicircuits RPD-1 mixer. 2) Drive your “device under test” into the other side of the RPD-1 3) Amplify and limit the output with a couple of OP-37 op amps running off of +/-15V. first stage is an amp with high pass and low pass sections second stage is an inverter / limiter (back to back diodes in a normal op amp inverter). third stage is same as the second you might (or might not) want a fourth stage 4) Feed the +/- 0.7 V limited output into a 5335 (DC couple the input) in talk only mode 5) Hook up the 5335 to a National Instruments GPIB card on a PC 6) Run a Visual Basic routine to grab the outputs and write them to a text file. 7) Process the text file with Excel. Use the ADEV formula from the original NIST papers. There have been a *lot* of OCXO’s tested that way in many different factories over a couple of decades. (Yes, it’s probably easier these days to substitute Time Lab for steps 6 and 7). Is it the ideal or perfect way to do it? Certainly not. It is one of many simple ways it can be done. Even this simple way has two forks in it (TimeLab or not). It also has a few features like a know good OCXO and the undocumented circuit on the output of the RPD-1. Quick, simple and pretty much useless to you. It’s my favorite way to do it, but that really should not make it your favorite. What to do? It’s really a multi part process. Break each section down and address it separately. You *do* have a goal in mind, but get each chunk running by it’s self. Do simple verifications each step of the way. Tie it all together at the end. Accept that you *will* spend
[time-nuts] Digital temperature compensation
I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Book info amazon http://www.amazon.com/American-Clocks-Volume-Special-Self-Winding/dp/0930163 443/ref=sr_1_sc_3?ie=UTF8qid=1414869823sr=8-3-spellkeywords=american+cloc ks+tran+duyly 73, Bill, WA2DVU Bill I responded to Mike there seems to be a number of threads running on this. So in fact you do have the telegraph coil in the clock. Makes sense to me. Thats why the 100 V they needed to drive 10-20 ma through the coil over distance and had to account for line loss. The boook you mention. Online? Regards Paul WB8TSL --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Mercury Ion Clock
Hi On Nov 1, 2014, at 2:35 PM, Jim Lux jim...@earthlink.net wrote: On 11/1/14, 11:05 AM, Magnus Danielson wrote: Jim, However, if you were happy with lab grade construction, and you have the Kurt Lesker and Duniway catalogs as bedside reading, I think you'd have a chance. Yes. I guess a bit of baking out the build is also to be recommended. I guess most of us don't do vacuum in our labs, so there is a challenge in itself, as there is many beginners mistakes to be done there. I haven't done high vacuum in quite a few years, but it is fascinating and frustrating. These days, quite a bit of surplus gear is out there that does make life easier (e.g. turbo molecular pumps). A Hg Ion system isn't real huge, and doesn't have a big gas load, so a straightforward LN2 sorption pump would probably work as a batch mode(e.g. a bunch of the right material, plunged into a LN bath, and it the gas molecules just stick right to the material.. ) The ion trap and such is a fairly straightforward thing, from what I understand: you need the usual vacuum pumps and such to build one. If you don't want it to run for years without servicing, then issues of the mercury content are less important. (BTW, the space clock uses thermal dissociation of HgO to get the mercury) Have tou cared to get the right isotope or do you use the natural abundance spreading? Hg-199 has an abundance of 16,87%. Interesting, I don't know if they go out and sort it, or if they set up the system so that it's basically a mass spec, and the wrong isotope doesn't make it through the quadrupole filter. Don’t in any way discount the amount of effort in getting that filter to work “right”. I'll bet the latter. No matter how good your offline enrichment process is, there will always be some other stuff in there. For all I know, the actual ion trap is specific to the mass of the ions. The PMT is an off the shelf thing. Check out the amateur built fusion reactor (fusor) websites on where to get PMTs and amplifiers (they're used behind a scintillator) Ah yes. Got a NaI(Tl) scintilator with about 1 cm copper filter and a matching PMT. No amp thought, but then again, I do not know what I should measure with it. :) You can measure radiation from common household objects like bananas The 40 GHz stuff these days is not nearly as exotic as it used to be. The challenge might be test equipment when you're debugging your 40 GHz synthesis chain. I was thinking the same, especially when consider optical clocks, then 40 GHz isn't as esoteric. Can you get this all done with 40 GHz as your “top” frequency? Traditional cesiums and rubidiums use a pair of synthesized frequencies being then sent into a step-recover diode inside a tuned cavity which then does the mixing and selects the right combination. Same scheme might work here. Next time I'm talking to one of the DSAC folks, I'll ask how they do the synthesis chain. I don't think it would be *easy*, but I think doable, and nothing in the system is particularly expensive or that exotic. It's sort of like telescope building.. The raw materials to make a 18 reflector telescope aren't all that expensive, nor is there some secret sauce: it's just time to grind the mirror (and recover from mistakes) and build the system. Would be a fun project to do, things to be learned. For when you get tired of counting femtoseconds.. Then you need to build a second one to check the first one with. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Hi Mike: The hourly synchronization 1 second wide pulse turns on a second prior to the top of the hour and off at the top. But . . . . it's not a low voltage pulse, but rather each clock is in a series loop where the external resistance is more than an order of magnitude higher than the internal resistance of the solenoid. That's because T = L/R for inductive circuits and using an external resistor lowers the time constant. When you use a DC source that has just enough voltage to pull in the solenoid the movement is very sluggish, but when there's an external resistor in the circuit the action is snappy and much stronger (to the point where for slave clocks it makes the difference between advancing and just wiggling without advancement). See for example the video at: http://www.prc68.com/I/SWCC.shtml#SC An energy efficient approach might be to start charging a large cap a minute prior to the top of the hour then discharge it through a series power resistor using a one second wide pulse that ends at the top of the hour. Note it takes more power to correct the clock if it's a couple minutes off than when it's on time, so there needs to be a lot of power in the pulse. PS the synchronizer by Ken's clocks uses a 4.5 V supply and is too weak to work on my clocks. PPS adding the series resistor is also needed in teletype circuits and for the same reason, to get faster action. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Mike Baker wrote: Hello, Time-Nutters-- A friend has a vintage oak-cabinet pendulum movement clock made by The Self Winding Clock Company some time around 1903. The company was formed in 1886. By the early 1900's era, this clock was known for its relative accuracy. These clocks were pendulum controlled and powered by a rather small and frequently reset mainspring that was wound hourly by a set of 1.5 VDC dry-cell batteries. In 1890 (?) the Naval Observatory agreed to telegraph standard railway time.Western Union, which also owned the Self-Winding Clock Company, sold these clocks to the railroads and sent the hourly time coordinating signals around the country by telegraph. My friend has one of the railroad clocks that has the Western Union Telegraph hourly resetting option. My friend thought it would be an interesting juxtaposition of technology from two different eras by creating the momentary 3-volt resetting pulse every hour from a GPS disciplined oscillator / clock pulse. I am wondering what the easiest approach to this might be?I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Mike Baker *** ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
Hi This sort of thing is normally done with a precisely controlled temperature chamber and multi day temperature ramp runs. Even then there is a bit of “wonder what that was, let’s try it again”. If you are looking at a crystal oscillator, what you have is a perturbation in the frequency / temperature curve. The response you get will be temperature rate of change dependent. Bob On Nov 1, 2014, at 4:40 PM, Dan Drown dan-timen...@drown.org wrote: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. temp-clock-warmer.pngtemp-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Bob: When we received new computers from HP and plugged them in the date/time was correct. I believe the DS32xx series of RTCs, like those in wrist watches run on almost no power. The trick is in getting a super cap with low leakage and low resistance. The super caps designed to keep memory chips alive may not power anything needing more than a microamp. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob On Oct 31, 2014, at 12:42 PM, Tom Miller tmiller11...@verizon.net wrote: I thought so too. There is an ultracap in each unit. Tom - Original Message - From: Mike Seguin n1...@burlingtontelecom.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 12:19 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby. I am using GPSCon to monitor and it appears to work fine. One thing on my units, when I power cycled them, it started a 'survey' over! I didn't expect that. Are others seeing this. There must be a way to store the surveyed position Tnx, Mike On 10/30/2014 3:59 PM, Bob Stewart wrote: Hi Anthony, Did you power cycle both units as part of connecting them together at J5 to J5? And can you remind me whether you are using the supplied interface cable, or are you using something else? After warmup, the ON light is on for the REF-0 unit and the STBY light is on for the REF-1 unit. While running, there is no output from J8 on the unit marked STBY. J8 works on the unit marked ON. There is a timestamp coming from J6, and I think a 1PPS signal on some pin or other. Bob From: Anthony Roby ar...@antamy.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, October 30, 2014 2:24 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system I'm still having no luck with mine. When I power on, the LEDs cycle, the Fault light is on and the No GPS and Standby lights flash. When I connect my GPS antenna, the No GPS light stops flashing and stays on. After several minutes only the Standby light is on. When I connect both the Ref1 and Ref0 together with the interface cable, the Fault lights on both units are illuminated. Do you see the same? I don't know what to infer from the Fault light since there is no supplemental data to work from. Anthony ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- 73, Mike, N1JEZ A closed mouth gathers no feet ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Digital temperature compensation
You could try submitting your data to zunzun.com It will fit it to around 40,000 different curves and find the best ones. Beware that with all curve fitting formulas, once your live data starts to wander out of the range of your original curve fit data, things can go rather badly... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all ? . ?? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
Thanks for this. I should have said that I have a Racal-Dana 1992 counter (with GPIB) and I have an Isotemp OCXO134-10, so its sounds like I just need the opamps, an RPD-1 and a GPIB-USB interface plus some software. I'll do a bit more digging around and see if I can get the GPIB up and running in the next couple of weeks. Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Saturday, November 01, 2014 3:18 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Measuring ADEV for a beginner Hi The problem with setting up to measure any of this stuff is that it ??s *very* dependent on the gear you have. There ??s no big surprises below. It ??s all ??spend more money and have fewer things to figure out ??. First you need a way to measure frequency out of your mixer (there are LOTS of ways ? ): If you grab a HP 5334 or HP 5335 to measure the frequency or time, you need to get the data out via GPIB. That ??s a project by it ??s self. If you grab a HP 53131 or CNT 90 to measure the frequency, you can use a serial port. One less project, way more money. If you grab a HP 5371, you just push a button and it pops up an ADEV plot. Less money than a 53131 (usually). It ??s a bit limited on the range it will do ADEV over. If you grab a brand new Symmetricom Time Pod, you spend (gulp!!) a bit more. You can now do measurements easily over it ??s frequency range. (If you can afford that option - can I come play at your house ?) Yes each of these is it ??s own little rabbit hole to wander down and each has it ??s own issues. Now you need a reference: GPSDO ??s have their fans, they often have spurs and other ??crud ?? on the output. They do have very good long term stability. OCXO ??s are often pretty quiet and spur free. You need some way to calibrate them for really long term stuff. Rb ??s come in a wide range of sizes and costs. Some are better than others. Their ADEV at 1 second often not as good as an OCXO. Cs standards and Hydrogen masers are (to me) in the same cost category as exotic test gear above. Fine for a company, not quite so easy for a basement guy. Again each of these is a bit of a project by it ??s self. Often it turns into a ??a couple of these and a couple of those ?? sort of solution. You only know something is right if you have another one to compare it to. Now you have some gear. Let ??s ignore building the mixer board and assume that ??s taken care of already. Now you need software: TimeLab is free and it will interface with many of the counters you might be using. It does all the math for you and puts up pretty plots. Highly recommended. There are other free software packages out there. Stable32 is another commonly used program. You need to get the data out of the counter before you can use it. There are other paid programs out there, Stable 32 is the best of the bunch. An Excel spread sheet is indeed another option. The ADEV math is *not* very complicated. Excel can do it all very easily. Getting data out of the counter could be a terminal program sort of thing (serial port) or something more complex (GPIB). In both cases there are a number of programs to pick between. With software, things like what computer and operating system you have will influence your choices. I ??m a Mac person, but I also run Linux, Windows, FreeBSD and a few other things as needed. Most people have a favorite ? . So, that ??s the quick and dirty start to the ??quick ADEV setup ?? process. There are: 4 counter like things X 4 reference ideas X (at least 4 mixer approaches) X (way more than) 4 software options = 256 paths you could follow. That ??s quite a few, and many of them would be utter nonsense. Even pruning out the ones are unlikely to ever be followed, you still have lots. Here ??s one: 1) Drive your ??known good ?? reference OCXO into a Minicircuits RPD-1 mixer. 2) Drive your ??device under test ?? into the other side of the RPD-1 3) Amplify and limit the output with a couple of OP-37 op amps running off of +/-15V. first stage is an amp with high pass and low pass sections second stage is an inverter / limiter (back to back diodes in a normal op amp inverter). third stage is same as the second you might (or might not) want a fourth stage 4) Feed the +/- 0.7 V limited output into a 5335 (DC couple the input) in talk only mode 5) Hook up the 5335 to a National Instruments GPIB card on a PC 6) Run a Visual Basic routine to grab the outputs and write them to a text file. 7) Process the text file with Excel. Use the ADEV formula from the original NIST papers. There have been a *lot* of OCXO ??s tested that way in many different factories over a couple of decades. (Yes, it ??s probably easier these days to substitute Time Lab for steps 6 and 7). Is it the ideal
Re: [time-nuts] Measuring ADEV for a beginner
Thanks - seems that I should be able to do this with my Racal-Dana 1992 counter. Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Saturday, November 01, 2014 1:29 PM To: time-nuts@febo.com Cc: mag...@rubidium.se Subject: Re: [time-nuts] Measuring ADEV for a beginner Anthony, On 11/01/2014 02:29 PM, Anthony Roby wrote: I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? The time-interval counter, such as HP5370 or SR620, get started (channel 1) by a reference clock, such as 1 PPS and is then stopped (channel 2) by signal under test. The counter is typically read out through GPIB, even if some counters have serial interface and maybe even USB or Ethernet for really new (or retro-fitted), and the recommended path is to get a GPIB to USB interface for instance. Then use John Miles TimeLab. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
Ok, I hadn't considered rate of change. This data is currently 3 day's worth and seems to repeat itself on both days at the same temperature point. Attached is a time based graph to show that. The ppm axis (on the right) is inverted to make it easier to see the relationship between the two. Quoting Bob Camp kb...@n1k.org: Hi This sort of thing is normally done with a precisely controlled temperature chamber and multi day temperature ramp runs. Even then there is a bit of “wonder what that was, let’s try it again”. If you are looking at a crystal oscillator, what you have is a perturbation in the frequency / temperature curve. The response you get will be temperature rate of change dependent. Bob On Nov 1, 2014, at 4:40 PM, Dan Drown dan-timen...@drown.org wrote: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. temp-clock-warmer.pngtemp-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Hi Hal: The click-click-click... is the self winding. A solenoid vibrates back and forth and a pawl and ratchet winds the main spring. https://www.youtube.com/watch?v=QIxOVo_0xgofeature=youtu.be Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Hal Murray wrote: We had something like that in school when I was a kid. (many years ago) I remember occasional click-click-click... as it got reset. mp...@clanbaker.org said: I am wondering what the easiest approach to this might be?I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Counting to 3600 won't work with leap seconds. :) I don't know the details of how a pulse sets the clock hands. I assume it can't set the time to a fraction of a pendulum swing so I don't see much use for something fancy like a GPSDO. But this is time-nuts, so anything is possible. I'd probably split the project into two parts. One is to keep good time on a computer, say something like a Raspberry Pi. You can use the net, or a low cost GPS unit, or something fancy like a GPSDO. The second part is how and when to generate the pulse. You can use GPIO pins, or modem control signals. You could use an old PC, but the payback due to reduced power will pay for a Raspberry Pi in a year or two depending on your power rates and how much power your old PC burns. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Setting Clocks in the Mid 1800's
Hi Larry: Yes, please. Here's my Dent Dipleidoscope: http://www.prc68.com/I/Dent.shtml Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Sanjeev Gupta wrote: On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid lmcda...@lmceng.com wrote: I gave a presentation on the Dent Dipleidoscope at the Harvard conference of the North American Sundial Society in 2013. If anyone is interested, I can provide a pdf of that presentation. The presentation includes history, detailed explanation of operation and lots of pictures of the construction of the dipleidoscope. (specifically on-list) Larry, I, for one, would appreciate your presentation. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 5300B - HP 5308A Counter Time Base...
Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?searchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. Thatâs not out of the likely adjustment range on the basic crystal reference on a 5308. Itâs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Selling time to the railroad
Hi Howard: From what I know the USNO used a Photographic Zenity Tube that made use of a pool of Mercury and glass plate that was exposed 4 times for a single star meridian crossing. The plate was then read using what amounts to a microscope and large X-Y table and after doing some math the exact time (within a millisecond or so) of the meridian crossing could be determined. Since the exposure was based on the observatory sidereal clock the answer was in sidereal time. This nighttime activity is needed to maintain the observatory clock. I suspect that the source of local time would be one of the ticks from the sidereal clock. So providing the noon or hourly time ticks is a different activity. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Howard Davidson wrote: The physics department at the little Liberal Arts college I went to in Iowa, Grinnell college, used to sell time to the Rock Island Railroad. We had two excellent pendulum clocks that back when this was in action, were synchronized to zenith crossings of particular stars. This was a manual operation performed by undergraduates who were paid to be up at weird hours of the night. The time ticks from the clocks were transmitted to the Rock Island station in town electrically. I presume they distributed it by telegraph. hld ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi Bob: AFAICR on the old 6-channel Motorola GPS boards there was an option for a backup battery. Without the backup battery if there was any power interruption the memory would erase and you needed to do a cold start. Having the almanac and ephemeris, even if from a year ago has the effect of greatly reducing start-up time. In this case the purpose of the super cap is to prevent memory loss because of a power glitch not for long term power failure. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi Well Q = CV. If delta V = 1 and C = 0.022 then Q = 0.022. That’s 22 ma for 1 second or 22 ua for 1,000 seconds. At 5 ua you would get to about an hour. If the delta V is 2X that, the times would all double. If the current is 10X lower than the spec (it might be …) then you could get out to around a day. Bob On Nov 1, 2014, at 12:38 AM, Bob Stewart b...@evoria.net wrote: Hi Bob et al, I don't understand the direction this question about the supercap has taken. It's connected to pin 1 of the GPS receiver. It looks to be a UT+, so that's the battery backup power. According to my UT+ manual the current draw on this pin is between 5uA (at 2.5V) and 100uA (at 5V)? How many hours will a .022F supercap keep at least 2.5V at that sort of discharge rate? Unless the cap has gone bad, it seems more likely that Bob's comment about it doing a fast survey and then doing a slower one in the background probably has merit. In fact, my unit goes through its survey mode pretty quickly on power up. So do those current/voltage figures imply several hours on the cap? Bob From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 9:22 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Didn't the clocks in cars back in the day use the same sort of thing to wind themselves? Though I remember a single click every x minutes, not the vibration of a solenoid. Bob From: Brooke Clarke bro...@pacific.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, November 1, 2014 4:14 PM Subject: Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock Hi Hal: The click-click-click... is the self winding. A solenoid vibrates back and forth and a pawl and ratchet winds the main spring. https://www.youtube.com/watch?v=QIxOVo_0xgofeature=youtu.be Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Hal Murray wrote: We had something like that in school when I was a kid. (many years ago) I remember occasional click-click-click... as it got reset. mp...@clanbaker.org said: I am wondering what the easiest approach to this might be? I suppose I could take the 1-sec pulses from a GPSDO (Trimble Thunderbolt ?) and count 3600 of them to generate a momentary reset 3VDC signal. In any event, I thought I would pass this by the Time-Nuts gang to see if any feedback is available as to what the least complicated (simplest) way might be to accomplish this. Counting to 3600 won't work with leap seconds. :) I don't know the details of how a pulse sets the clock hands. I assume it can't set the time to a fraction of a pendulum swing so I don't see much use for something fancy like a GPSDO. But this is time-nuts, so anything is possible. I'd probably split the project into two parts. One is to keep good time on a computer, say something like a Raspberry Pi. You can use the net, or a low cost GPS unit, or something fancy like a GPSDO. The second part is how and when to generate the pulse. You can use GPIO pins, or modem control signals. You could use an old PC, but the payback due to reduced power will pay for a Raspberry Pi in a year or two depending on your power rates and how much power your old PC burns. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Self-setting / self-winding clock
Hi Mike: There's a heart shaped cam that forces the hour, minute and if the clock has one the second hand to 12:00 and holds them there until the sync pulse goes away. Note the second hand only was used on clocks in radio stations so they could join the network. For that 1 second was close enough. http://www.prc68.com/I/SWCC2.shtml Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Mike Baker wrote: Time-Nutters-- This particular 1903 Railroad self-setting/winding pendulum regulated clock needed only an hourly signal from a Western Union telegraph line to provide momentary closure of a relay contact. This supplied +3 VDC to rewind the spring and also reset the sweep seconds hand on the hour, every hour. From what I have learned about this, the resetting of the sweep seconds hand is mechanically coordinated to occur when the pendulum is at either end of its swing. It appears that is no way (that I know of) to guarantee that the telegraphed reset pulse would coincide with either end of the pendulum's travel. Apparently, the resetting of the sweep seconds hand will only occur within the time frame of any single pendulum swing. I suppose this means that the clock might be in error by as much as nearly one swing of the pendulum because it has to reach the end of its swing before the second hand is reset. Just guessing here, but I am thinking that all this clock needs is a 1-second long closure of a relay contact on the hour, every hour. I don't think that leap-seconds are an issue here as the clock can be manually adjusted for that whenever a leap second occurs. So-- it comes back to counting 3600 one-second pulses from a GPS clock...? Or am I missing something here...? Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10MHz Rubidium reference source for frequency counter
On Fri, 31 Oct 2014 23:40:04 -0400, you wrote: John wrote: It seems to me that it's just a case of expecting too much from a counter. Possibly, but a well-tuned 5370B can get to the low e-12's at 1-10 seconds. It has better one-shot resolution than the Pendulum, but not by a factor of 10. So, I'd have thought the Pendulum would at least get to the mid e-11's if the time base was up to it. The 'Smart Freq' feature on the CNT-91 appears to do multiple measurements over the gate time to get an improved resolution, kind of like the 53131/2. In practice, when 11 digits or whatever are claimed, I usually find that there is just a little bit of information in the last digit, not that it's a solid reading to that number of digits. In the Measurement Uncertainties section of the manual, would the formula for frequency suggest that Smart Freq makes the result up from multiple measurements of 0.4 times the nominal gate time? To get the best performance from a counter, you need to set up the trigger thresholds well away from ground as Charles says. Also consider taking TI readings rather than frequency readings. Frequency readings are OK for initial setup and basic ADEV comparisons but they won't generally yield the best ADEV fidelity or the lowest possible measurement floor. Yes, using TI mode is essential for getting down to the counter's limits. Was Karen using frequency mode? I wasn't paying attention to that end of things. I don't know exactly how the CNT-91 does it, but the older CNT-81 can do a lot of measurements in Time Interval A to B mode. With a static delay, my 6681 gives a SD of about 0.22ps for a set of 100 1-second measurements (a 10MHz square wave was driving the inputs). One little thing I noticed there was that the reference freq needed to be at least 3ppm off the input frequency to get quite that low. The newer series seem to need a bit of an offset too: https://www.febo.com/pipermail/time-nuts/2014-September/086701.html Angus. Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
I gave zunzun a try and the one with the lowest root mean squared error was: f(x) = a( x**0.5) + b( x ) + c( sin(x) ) + d( cos(x) ) It got 0.202 RMSE, so I guess I'll stick with my original function as it seems to be closer to what I expect will happen at colder/hotter temps. You have a good point about temperatures outside my data samples. Once it gets hot again in the summertime, I'm sure I'll have to re-evaluate this. Quoting Mark Sims hol...@hotmail.com: You could try submitting your data to zunzun.com It will fit it to around 40,000 different curves and find the best ones. Beware that with all curve fitting formulas, once your live data starts to wander out of the range of your original curve fit data, things can go rather badly... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10MHz Rubidium reference source for frequency counter
Hal wrote: Yes, using TI mode is essential for getting down to the counter's limits. What's going on there? It's just a divide, right? Is the firmware not smart enough to do get enough precision? Do all counters have that problem? The raw TI data have all of the benefit of the interpolation done by the basic TI counter. To get frequency (or period), the counter divides the TI into (or by) the event count, which is an integer that is more granular than the interpolated TI result. This reduces precision (not necessarily by a huge amount, since it's typically a big integer) and has the potential to introduce periodic anomalies into the data. To my knowledge, all TI-based counters behave this way. Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
bro...@pacific.net said: The click-click-click... is the self winding. A solenoid vibrates back and forth and a pawl and ratchet winds the main spring. I don't think that's what I was referring to. It was a long time ago so my memory may be buggy. The click-click-click... that I remember was loud enough to distract the class. It only happened occasionally, ballpark of once per month or less. The minute hand was making a step with each click. I assumed there was some mechanism to remotely set the clock. I think it ended up roughly correct. (I didn't even have a watch back then.) Was there any alternative to SWCC technology in the 1950s time frame? There's a heart shaped cam that forces the hour, minute and if the clock has one the second hand to 12:00 and holds them there until the sync pulse goes away. Note the second hand only was used on clocks in radio stations so they could join the network. For that 1 second was close enough. Is that one cam that gets all the hands or a separate cam for each hand? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system
Hi I think if you look at the math, the 0.022 F cap isn’t going to take care of the rated 20 uA current drain for very long. Bob On Nov 1, 2014, at 4:59 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When we received new computers from HP and plugged them in the date/time was correct. I believe the DS32xx series of RTCs, like those in wrist watches run on almost no power. The trick is in getting a super cap with low leakage and low resistance. The super caps designed to keep memory chips alive may not power anything needing more than a microamp. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi I sort of doubt that a GPS aux supply is quite that low current. I have seen some RTC’s that won’t last a month on a coin cell. My recollection is that the Oncore backup is closer to that category than the “many years on a cap” group. Bob On Oct 31, 2014, at 9:26 PM, Brooke Clarke bro...@pacific.net wrote: Hi Bob: When HP came out with the 300 series Rocky Mountain Basic computers they were fitted with a super cap to power the RTC. I will keep time for some months. http://www.prc68.com/I/HPIB.shtml#300 Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Bob Camp wrote: Hi The ultra cap is a pretty small one (physical small). You might be able to find a larger (more farads) one that would fit in the same space. It’s not going to help for a hours and hours sort of outage. It might get you from dying in 15 minutes to dying in a half hour. Bob On Oct 31, 2014, at 12:42 PM, Tom Miller tmiller11...@verizon.net wrote: I thought so too. There is an ultracap in each unit. Tom - Original Message - From: Mike Seguin n1...@burlingtontelecom.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, October 31, 2014 12:19 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby. I am using GPSCon to monitor and it appears to work fine. One thing on my units, when I power cycled them, it started a 'survey' over! I didn't expect that. Are others seeing this. There must be a way to store the surveyed position Tnx, Mike On 10/30/2014 3:59 PM, Bob Stewart wrote: Hi Anthony, Did you power cycle both units as part of connecting them together at J5 to J5? And can you remind me whether you are using the supplied interface cable, or are you using something else? After warmup, the ON light is on for the REF-0 unit and the STBY light is on for the REF-1 unit. While running, there is no output from J8 on the unit marked STBY. J8 works on the unit marked ON. There is a timestamp coming from J6, and I think a 1PPS signal on some pin or other. Bob From: Anthony Roby ar...@antamy.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, October 30, 2014 2:24 PM Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system I'm still having no luck with mine. When I power on, the LEDs cycle, the Fault light is on and the No GPS and Standby lights flash. When I connect my GPS antenna, the No GPS light stops flashing and stays on. After several minutes only the Standby light is on. When I connect both the Ref1 and Ref0 together with the interface cable, the Fault lights on both units are illuminated. Do you see the same? I don't know what to infer from the Fault light since there is no supplemental data to work from. Anthony ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- 73, Mike, N1JEZ A closed mouth gathers no feet ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe,
Re: [time-nuts] Measuring ADEV for a beginner
ar...@antamy.com said: I'll do a bit more digging around and see if I can get the GPIB up and running in the next couple of weeks. I've been happy with the ProLogic GPIB-USB gizmo. https://www.sparkfun.com/products/549 It took some fiddling to get going, but I like chasing that sort of thing. http://www.megapathdsl.net/~hmurray/hacks/probe.c -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all ? . ?? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
Hi On Nov 1, 2014, at 5:09 PM, Dan Drown dan-timen...@drown.org wrote: Ok, I hadn't considered rate of change. It’s one of the limits on this sort of thing in general. It’s even more of an issue with a coupled mode like the one you show. Since there are an enormous number of possible variables, it’s always tough to know exactly how much of an issue you will have. One common answer - run your profile runs at the temperature change rate you are most likely to see in practice. Another very common answer - don’t use that crystal, get one that does not have the problem. You can get parts with slopes 0.1 ppm / C over 10 to 50 C. You might have to spend some quality time sorting them out …. Bob This data is currently 3 day's worth and seems to repeat itself on both days at the same temperature point. Attached is a time based graph to show that. The ppm axis (on the right) is inverted to make it easier to see the relationship between the two. Quoting Bob Camp kb...@n1k.org: Hi This sort of thing is normally done with a precisely controlled temperature chamber and multi day temperature ramp runs. Even then there is a bit of “wonder what that was, let’s try it again”. If you are looking at a crystal oscillator, what you have is a perturbation in the frequency / temperature curve. The response you get will be temperature rate of change dependent. Bob On Nov 1, 2014, at 4:40 PM, Dan Drown dan-timen...@drown.org wrote: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. temp-clock-warmer.pngtemp-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. temp-vs-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi It’s an added circuit you need to build up and add to the box. It fakes out the slave detection logic. Bob On Nov 1, 2014, at 6:41 PM, Anthony Roby ar...@antamy.com wrote: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all ? . ?? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list
Re: [time-nuts] Digital temperature compensation
dan-timen...@drown.org said: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. This is for ntpd rather than chrony, but it's a good read: NTP temperature compensation http://www.ijs.si/time/temp-compensation/ With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. That section of the graph doesn't make sense to me. I suspect a glitch in your setup. When does your GPS unit run out of satellites? Where is your temperature probe? Is it in contact with the crystal inside the PC? Is the PC doing anything? In particular at the times when the data doesn't make sense? PCs can do a lot of self heating. Try running a big workload when the temperature is in the middle of the good range. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi Anthony, It's a new circuit that has to be inserted, which is what I've done, but I'm not sure whether or not it's strictly necessary for the unit to function or whether it's just there to get the lights sequencing properly and perhaps all that's needed for basic functionality are just the links. I'm leaving well alone for now to let the oscillator run overnight but will try it again tomorrow with just the links and see what happens. I'm also hoping to get some idea of the between unit signalling, although I only have Z3811s I'm hoping, with the boards being an almost identical match, that what goes one way should be matched by what comes the other. Regards Nigel GM8PZR In a message dated 01/11/2014 22:41:09 GMT Standard Time, ar...@antamy.com writes: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a power supply -see photo) allows the lights to cycle through their normal sequence on warm-up and the second unit isn't needed at all ? . ?? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock
Hi Hal: I think there were a number of slave clock systems and some of them could do DST/ST changes and/or catch up from a power failure. That very well might have been what you heard. To me the winding sounds like a muffled air compressor. The setting sounds like Thunk. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Hal Murray wrote: bro...@pacific.net said: The click-click-click... is the self winding. A solenoid vibrates back and forth and a pawl and ratchet winds the main spring. I don't think that's what I was referring to. It was a long time ago so my memory may be buggy. The click-click-click... that I remember was loud enough to distract the class. It only happened occasionally, ballpark of once per month or less. The minute hand was making a step with each click. I assumed there was some mechanism to remotely set the clock. I think it ended up roughly correct. (I didn't even have a watch back then.) Was there any alternative to SWCC technology in the 1950s time frame? There's a heart shaped cam that forces the hour, minute and if the clock has one the second hand to 12:00 and holds them there until the sync pulse goes away. Note the second hand only was used on clocks in radio stations so they could join the network. For that 1 second was close enough. Is that one cam that gets all the hands or a separate cam for each hand? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
If this is just for holdover then I don't think you even want a general solution. Have the controller always keep the last few days of data for temperature vs. EFC value. Then if GPS fails use the most recent data for the current temperature. This makes for a self adapting system accounting for aging too. Not just crystal aging but the aging of the resisters, the temperature sensor itself and other components. I don't think holdover should fall back onto a model that was created from data that might be months or years old. Use hours or days old data. This will give the desired response which is this: If the temperature is constant when the GPS fails the EFC value as determined by your holdover temperature modeling should give you the EXACT same EFC value as just before the GPS failure. I don't think you can do that with a model. You'd nee to use logged data. On Sat, Nov 1, 2014 at 4:01 PM, Bob Camp kb...@n1k.org wrote: Hi On Nov 1, 2014, at 5:09 PM, Dan Drown dan-timen...@drown.org wrote: Ok, I hadn't considered rate of change. It’s one of the limits on this sort of thing in general. It’s even more of an issue with a coupled mode like the one you show. Since there are an enormous number of possible variables, it’s always tough to know exactly how much of an issue you will have. One common answer - run your profile runs at the temperature change rate you are most likely to see in practice. Another very common answer - don’t use that crystal, get one that does not have the problem. You can get parts with slopes 0.1 ppm / C over 10 to 50 C. You might have to spend some quality time sorting them out …. Bob This data is currently 3 day's worth and seems to repeat itself on both days at the same temperature point. Attached is a time based graph to show that. The ppm axis (on the right) is inverted to make it easier to see the relationship between the two. Quoting Bob Camp kb...@n1k.org: Hi This sort of thing is normally done with a precisely controlled temperature chamber and multi day temperature ramp runs. Even then there is a bit of “wonder what that was, let’s try it again”. If you are looking at a crystal oscillator, what you have is a perturbation in the frequency / temperature curve. The response you get will be temperature rate of change dependent. Bob On Nov 1, 2014, at 4:40 PM, Dan Drown dan-timen...@drown.org wrote: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. temp-clock-warmer.pngtemp-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. temp-vs-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
Mmmm yes you can see the equation evaluation starting to rise in your Warmer plot, as Mark says, which will make a nonsense of the formula if your summer temps get above 28. Why not a table and then interpolate between the table data points?. You might have more points where the changes are greater. The colder plot looks cubic maybe for a crystal made for 20 deg C ?? But depending on the oscillator electronics you may have component tempcos affecting the frequency as well? I suspect the turnover at 21deg C should be a smooth curve not as your formula predicts. Which suggests that you have too too high an order of polynomial I think, but you may not get a good fit with a cubic if other effects are present. Alan G3NYK - Original Message - From: Dan Drown dan-timen...@drown.org To: time-nuts@febo.com Sent: Saturday, November 01, 2014 10:07 PM Subject: Re: [time-nuts] Digital temperature compensation I gave zunzun a try and the one with the lowest root mean squared error was: f(x) = a( x**0.5) + b( x ) + c( sin(x) ) + d( cos(x) ) It got 0.202 RMSE, so I guess I'll stick with my original function as it seems to be closer to what I expect will happen at colder/hotter temps. You have a good point about temperatures outside my data samples. Once it gets hot again in the summertime, I'm sure I'll have to re-evaluate this. Quoting Mark Sims hol...@hotmail.com: You could try submitting your data to zunzun.com It will fit it to around 40,000 different curves and find the best ones. Beware that with all curve fitting formulas, once your live data starts to wander out of the range of your original curve fit data, things can go rather badly... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi If you: 1) Do not have two units (Ref 0 and Ref 1) — and — 2) Do not “fake out” the slave detect (= use the mod) Then the unit you have will not: 1) Enable the pps out 2) Enable the 15 MHz out It will try to disciple the OCXO, but you won’t be able to see any result of that. Bob On Nov 1, 2014, at 7:05 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Anthony, It's a new circuit that has to be inserted, which is what I've done, but I'm not sure whether or not it's strictly necessary for the unit to function or whether it's just there to get the lights sequencing properly and perhaps all that's needed for basic functionality are just the links. I'm leaving well alone for now to let the oscillator run overnight but will try it again tomorrow with just the links and see what happens. I'm also hoping to get some idea of the between unit signalling, although I only have Z3811s I'm hoping, with the boards being an almost identical match, that what goes one way should be matched by what comes the other. Regards Nigel GM8PZR In a message dated 01/11/2014 22:41:09 GMT Standard Time, ar...@antamy.com writes: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that I needed to connect them together to get the REF1 unit to come out of standby ? . ?? Bob Camp kb8tq at n1k.org ??I suspect that somebody will have to figure out what the 15 pin connector / jumper is doing. On previous RFTG units there was a way to re-wire the crossover interface to fake out the slave detect process. That would let you run a single GPS equipped box and have it behave correctly. Without the fake wires trick none of them played nice without the slave being present ? . ?? ++ Reposting what I had posted over a week ago, in case you missed it ? . Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 ?? ? Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of these units I had modified but at the time there wasn't a single person who was interested. I have been using the RFTG-u REF1 since then and it is a nice unit. The modifications I added (including a
[time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?s earchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. ThatâÂÂs not out of the likely adjustment range on the basic crystal reference on a 5308. ItâÂÂs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Digital temperature compensation
I think you have a good point - any model is going to have a larger error than the data itself. I'll be looking into this. Quoting Chris Albertson albertson.ch...@gmail.com: If this is just for holdover then I don't think you even want a general solution. Have the controller always keep the last few days of data for temperature vs. EFC value. Then if GPS fails use the most recent data for the current temperature. This makes for a self adapting system accounting for aging too. Not just crystal aging but the aging of the resisters, the temperature sensor itself and other components. I don't think holdover should fall back onto a model that was created from data that might be months or years old. Use hours or days old data. This will give the desired response which is this: If the temperature is constant when the GPS fails the EFC value as determined by your holdover temperature modeling should give you the EXACT same EFC value as just before the GPS failure. I don't think you can do that with a model. You'd nee to use logged data. On Sat, Nov 1, 2014 at 4:01 PM, Bob Camp kb...@n1k.org wrote: Hi On Nov 1, 2014, at 5:09 PM, Dan Drown dan-timen...@drown.org wrote: Ok, I hadn't considered rate of change. It’s one of the limits on this sort of thing in general. It’s even more of an issue with a coupled mode like the one you show. Since there are an enormous number of possible variables, it’s always tough to know exactly how much of an issue you will have. One common answer - run your profile runs at the temperature change rate you are most likely to see in practice. Another very common answer - don’t use that crystal, get one that does not have the problem. You can get parts with slopes 0.1 ppm / C over 10 to 50 C. You might have to spend some quality time sorting them out …. Bob This data is currently 3 day's worth and seems to repeat itself on both days at the same temperature point. Attached is a time based graph to show that. The ppm axis (on the right) is inverted to make it easier to see the relationship between the two. Quoting Bob Camp kb...@n1k.org: Hi This sort of thing is normally done with a precisely controlled temperature chamber and multi day temperature ramp runs. Even then there is a bit of “wonder what that was, let’s try it again”. If you are looking at a crystal oscillator, what you have is a perturbation in the frequency / temperature curve. The response you get will be temperature rate of change dependent. Bob On Nov 1, 2014, at 4:40 PM, Dan Drown dan-timen...@drown.org wrote: I'm experimenting with using a temperature sensor to estimate local oscillator frequency changes. My goal is to have a decent holdover clock for a NTP server with not so great GPS antenna placement. I've been sampling temperature every minute, measured by a DS18B20. I've been measuring local clock frequency differences, using chronyd's logs from the GPS's PPS. At 28C through 21C, I get a pretty good result that fits a quadratic polynomial decently (0.117 ppm stddev). I've attached the graph of that as temp-clock-warmer.png. With the colder temperatures, there's a sudden drop off in frequency that I'm having a hard time finding a equation that fits as nicely. All the examples I can find on the web look like third degree polynomials, while my data doesn't seem to fit that exactly. The best result I've had so far (0.198 ppm stddev) is attached as temp-clock.png and uses the function: f(x) = -abs(a * (x - 20.88)) + b * ((x - 20.88)**2) + c * ((x - 20.88)**3) a = 0.888582 b = 0.113806 c = -0.00445763 Does anyone have any advice on how to better model this? Has anyone seen this behavior? I can provide the raw data if that would help any. temp-clock-warmer.pngtemp-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. temp-vs-clock.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com
[time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Keep in mind that I made the modifications to my RFTG-u REF 1 almost 4 years ago and the details of why I did what I did are kind of foggy today. It was a pure hack but I *believe* that the circuitry as well as the jumpers were required, or at least I thought so. The big problem with getting something like this to work is that after spending a lot of time on it I generally go on to the next project and as long as what I did works, I forget about it because it is a one of a kind thing. The photo link below shows the 5Mhz buffer amp I connected to the TP in front of the oscillator that uses a mounting bracket that is secured by the BNC connector that outputs the 5Mhz. The 24V/2A power supply that I mounted on the back connects across the diode on the circuit board as shown. The transistors and other components of the modification that are mounted free form on the back of the J5 connector get the +5VDC from the header directly in back of J5. The wire on the left goes through an existing hole on the circuit board to connect to the fault LED. I was hoping that someone else would duplicate the modification just to reassure me that what I did wasn't black magic. It looks like Nigel is doing just that-thanks. http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1_zps546e4c82.jpg ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
Hi If the OCXO was not heating, it would be off by about 20 to 60 Hz. It’s close enough that it is getting power and heating up. If it does move when you fiddle the trimmer, that part is likely still connected. It sounds like the beast has simply aged further than it’s trim range. Bob On Nov 1, 2014, at 8:39 PM, Burt I. Weiner b...@att.net wrote: The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?s earchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. ThatâÂÂs not out of the likely adjustment range on the basic crystal reference on a 5308. ItâÂÂs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi Bob, I understand the consequences of not modifying the unit but, having done so and having a REF-1 unit running stand alone, I was just commenting that I wasn't sure whether or not it was necessary to implement all of Arthur's modification in order to enable the basic functionality, or whether some part of it might be purely to control the indicators. As a follow on from that I was wondering whether or not it might be possible to achieve a similar result, at least to the point of just making it functional, just by cross linking some of the out and return paths, faking it without the need for an additional powered interface if you like, not for any other reason than it might then be possible to make a plug in modification that could be fitted without needing to open the box. Regards Nigel GM8PZR In a message dated 02/11/2014 00:19:57 GMT Standard Time, kb...@n1k.org writes: Hi If you: 1) Do not have two units (Ref 0 and Ref 1) — and — 2) Do not “fake out” the slave detect (= use the mod) Then the unit you have will not: 1) Enable the pps out 2) Enable the 15 MHz out It will try to disciple the OCXO, but you won’t be able to see any result of that. Bob On Nov 1, 2014, at 7:05 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Anthony, It's a new circuit that has to be inserted, which is what I've done, but I'm not sure whether or not it's strictly necessary for the unit to function or whether it's just there to get the lights sequencing properly and perhaps all that's needed for basic functionality are just the links. I'm leaving well alone for now to let the oscillator run overnight but will try it again tomorrow with just the links and see what happens. I'm also hoping to get some idea of the between unit signalling, although I only have Z3811s I'm hoping, with the boards being an almost identical match, that what goes one way should be matched by what comes the other. Regards Nigel GM8PZR In a message dated 01/11/2014 22:41:09 GMT Standard Time, ar...@antamy.com writes: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014 15:25:02 GMT Standard Time, ar...@antamy.com writes: For those who missed it, Arthur's post is at https://www.febo.com/pipermail/time-nuts/2010-June/047825.html and the photo is at http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1photo1_zps87c505ca.jpg Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur Dent Sent: Friday, October 31, 2014 9:20 PM To: time-nuts@febo.com Subject: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Bob Stewart bob at evoria.net ?? ? I have both of my units sitting on the bench. I found that
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi I’ve watched the two boxes fire up. They spend a bit of time blinking lights on this one and then on that one. From watching the “dance”, I think that the transistor delay circuit (or something like it) is indeed needed. There are multiple ways the delay and sequencing could be implemented. A cheap 5V PIC is certainly one way to do it. With no voltage coming out on the connector doing a purely external solution probably is going to require external power. I think I’d at least bring that out on one of the many unused alarm pins. Bob On Nov 1, 2014, at 9:52 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Bob, I understand the consequences of not modifying the unit but, having done so and having a REF-1 unit running stand alone, I was just commenting that I wasn't sure whether or not it was necessary to implement all of Arthur's modification in order to enable the basic functionality, or whether some part of it might be purely to control the indicators. As a follow on from that I was wondering whether or not it might be possible to achieve a similar result, at least to the point of just making it functional, just by cross linking some of the out and return paths, faking it without the need for an additional powered interface if you like, not for any other reason than it might then be possible to make a plug in modification that could be fitted without needing to open the box. Regards Nigel GM8PZR In a message dated 02/11/2014 00:19:57 GMT Standard Time, kb...@n1k.org writes: Hi If you: 1) Do not have two units (Ref 0 and Ref 1) — and — 2) Do not “fake out” the slave detect (= use the mod) Then the unit you have will not: 1) Enable the pps out 2) Enable the 15 MHz out It will try to disciple the OCXO, but you won’t be able to see any result of that. Bob On Nov 1, 2014, at 7:05 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Anthony, It's a new circuit that has to be inserted, which is what I've done, but I'm not sure whether or not it's strictly necessary for the unit to function or whether it's just there to get the lights sequencing properly and perhaps all that's needed for basic functionality are just the links. I'm leaving well alone for now to let the oscillator run overnight but will try it again tomorrow with just the links and see what happens. I'm also hoping to get some idea of the between unit signalling, although I only have Z3811s I'm hoping, with the boards being an almost identical match, that what goes one way should be matched by what comes the other. Regards Nigel GM8PZR In a message dated 01/11/2014 22:41:09 GMT Standard Time, ar...@antamy.com writes: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required. Whether or not this is part or all of the reason that my green on light is flashing rather than steady I don't know, but I am seeing the 1PPS and 15MHz outputs and the 15MHz looks to be conditioning ok. Aside from the 5 volt supply, which I'm picking off from pin 5 of the header between u33 and U34, and the aforementioned fault LED connection, all the other connections can be made to J5 externally and could be housed in a 15 way shell along with the switching circuits. I'm still hopeful that some cross linking of the right pairs might achieve the same result without the extra circuitry, so all that needs to be done now is just to identify the right pairs:-) At least with it up and running it should be easier to check out some of the inter-unit signalling. Thanks Arthur, your efforts are much appreciated. regards Nigel GM8PZR In a message dated 01/11/2014
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
Hi Arthur, Thanks for the extra information, it sounds like you may well have answered my question:-) As I commented to Bob, I was hoping I might be able to find an option that didn't require any internal access, I knew that was a long shot anyway but I quite liked the idea of a plug and go solution. Anyway, I can assure you that what you did wasn't just black magic, or at least that if it was the magic still works:-) Regards Nigel GM8PZR In a message dated 02/11/2014 01:27:18 GMT Standard Time, golgarfrinc...@gmail.com writes: Keep in mind that I made the modifications to my RFTG-u REF 1 almost 4 years ago and the details of why I did what I did are kind of foggy today. It was a pure hack but I *believe* that the circuitry as well as the jumpers were required, or at least I thought so. The big problem with getting something like this to work is that after spending a lot of time on it I generally go on to the next project and as long as what I did works, I forget about it because it is a one of a kind thing. The photo link below shows the 5Mhz buffer amp I connected to the TP in front of the oscillator that uses a mounting bracket that is secured by the BNC connector that outputs the 5Mhz. The 24V/2A power supply that I mounted on the back connects across the diode on the circuit board as shown. The transistors and other components of the modification that are mounted free form on the back of the J5 connector get the +5VDC from the header directly in back of J5. The wire on the left goes through an existing hole on the circuit board to connect to the fault LED. I was hoping that someone else would duplicate the modification just to reassure me that what I did wasn't black magic. It looks like Nigel is doing just that-thanks. http://i906.photobucket.com/albums/ac262/rjb1998/RFTG-uREF1_zps546e4c82.jpg ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Measuring ADEV for a beginner
That will work as a starting-point. When you look at your ADEV plot, you will notice a 1/tau curve for the lower taus, that is due to your counters limitations. If you need to go below that, you need a better counter, but for the moment you should start believe the plot as it flattens out, that has more to do with your signal, unless that is the same as your reference or a very high measurement floor of the counter. A good test is to split your reference into the start and stop inputs, and then measure the amount of noise you have. Preferably with a slightly longer cable to the stop channel. This will give you the noise floor of the counter, for that signaltype and trigger-point. There are ways to improve things if your noise is higher than the single-shot resolution, as you read out the ADEV at tau=1s. Cheers, Magnus On 11/01/2014 09:43 PM, Anthony Roby wrote: Thanks - seems that I should be able to do this with my Racal-Dana 1992 counter. Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Saturday, November 01, 2014 1:29 PM To: time-nuts@febo.com Cc: mag...@rubidium.se Subject: Re: [time-nuts] Measuring ADEV for a beginner Anthony, On 11/01/2014 02:29 PM, Anthony Roby wrote: I've been reading a lot about ADEV and following the threads on the list, particularly Karen's in-flight thread. What I haven't come across is a simple explanation of the basic setup required to go about collecting the data. John Miles referenced this page http://www.ke5fx.com/tpll.htm, and the simple setup at the bottom of the page looks like a reasonable place to start. Seems that I'd need to acquire a phase detector and build or buy some filters and the amp. I can probably figure that out, but how do I get the data into a PC? Is there a basic hardware and software setup that someone could point me to or recommend? The time-interval counter, such as HP5370 or SR620, get started (channel 1) by a reference clock, such as 1 PPS and is then stopped (channel 2) by signal under test. The counter is typically read out through GPIB, even if some counters have serial interface and maybe even USB or Ethernet for really new (or retro-fitted), and the recommended path is to get a GPIB to USB interface for instance. Then use John Miles TimeLab. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Setting Clocks in the Mid 1800's
Yes, that is one of the original 1843 dipleidoscope designs. All the
original black finish seems to have been polished away, however.
This original design used a lot of expensive brass. Later models used a
cast brass {scroll base and a dipleidoscope body machined from a round
brass bar; this could be used for either the British Isles or for the
India model.
Larry
On 11/1/2014 2:16 PM, Brooke Clarke wrote:
Hi Larry:
Yes, please.
Here's my Dent Dipleidoscope:
http://www.prc68.com/I/Dent.shtml
Mail_Attachment --
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
http://www.prc68.com/I/DietNutrition.html
Sanjeev Gupta wrote:
On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid lmcda...@lmceng.com
wrote:
I gave a presentation on the Dent Dipleidoscope at the Harvard
conference
of the North American Sundial Society in 2013. If anyone is
interested, I
can provide a pdf of that presentation. The presentation includes
history,
detailed explanation of operation and lots of pictures of the
construction
of the dipleidoscope.
(specifically on-list)
Larry, I, for one, would appreciate your presentation.
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--
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
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and follow the instructions there.
Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812...
That's one down side of course of only buying the REF-1 units, not having any idea of the normal behaviour. It's certainly sounding like any hopes of a purely passive solution is one for the wishful thinking department. I'd still like to minimise any internal modifications, and mounting Arthur's switching circuit inside a connector body wouldn't be difficult, so will still check to see if there's any way of routing power out via the 15 way connector. That still leaves the fault light connection but I was pretty sure I've already established that just holding that input high to match the fault light would enable it to start up ok but fiddling with it just now I'm back to a fault light and not outputs. Perhaps I should have left well alone:-) Regards Nigel GM8PZR In a message dated 02/11/2014 02:00:23 GMT Standard Time, kb...@n1k.org writes: Hi I’ve watched the two boxes fire up. They spend a bit of time blinking lights on this one and then on that one. From watching the “dance”, I think that the transistor delay circuit (or something like it) is indeed needed. There are multiple ways the delay and sequencing could be implemented. A cheap 5V PIC is certainly one way to do it. With no voltage coming out on the connector doing a purely external solution probably is going to require external power. I think I’d at least bring that out on one of the many unused alarm pins. Bob On Nov 1, 2014, at 9:52 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Bob, I understand the consequences of not modifying the unit but, having done so and having a REF-1 unit running stand alone, I was just commenting that I wasn't sure whether or not it was necessary to implement all of Arthur's modification in order to enable the basic functionality, or whether some part of it might be purely to control the indicators. As a follow on from that I was wondering whether or not it might be possible to achieve a similar result, at least to the point of just making it functional, just by cross linking some of the out and return paths, faking it without the need for an additional powered interface if you like, not for any other reason than it might then be possible to make a plug in modification that could be fitted without needing to open the box. Regards Nigel GM8PZR In a message dated 02/11/2014 00:19:57 GMT Standard Time, kb...@n1k.org writes: Hi If you: 1) Do not have two units (Ref 0 and Ref 1) — and — 2) Do not “fake out” the slave detect (= use the mod) Then the unit you have will not: 1) Enable the pps out 2) Enable the 15 MHz out It will try to disciple the OCXO, but you won’t be able to see any result of that. Bob On Nov 1, 2014, at 7:05 PM, GandalfG8--- via time-nuts time-nuts@febo.com wrote: Hi Anthony, It's a new circuit that has to be inserted, which is what I've done, but I'm not sure whether or not it's strictly necessary for the unit to function or whether it's just there to get the lights sequencing properly and perhaps all that's needed for basic functionality are just the links. I'm leaving well alone for now to let the oscillator run overnight but will try it again tomorrow with just the links and see what happens. I'm also hoping to get some idea of the between unit signalling, although I only have Z3811s I'm hoping, with the boards being an almost identical match, that what goes one way should be matched by what comes the other. Regards Nigel GM8PZR In a message dated 01/11/2014 22:41:09 GMT Standard Time, ar...@antamy.com writes: I wasn't clear from the photo whether the circuit was a representation of what is on the board, and you just had to connect the pins listed together, or whether this was a new circuit that had to be inserted. Sounds like the latter? Anthony -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of GandalfG8--- via time-nuts Sent: Saturday, November 01, 2014 4:04 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812... Well, I'm happy to report that Arthur's modification does do the trick, although I don't know why as I don't have any data for the interface as yet. I daren't disturb the 15 pin connector right now as this Z3811A PCB is still out of its case and connected to a breadboard with wires just pushed into the sockets, and for the same reason I don't have any computer connection at the moment either. My implementation isn't quite as described, in that I've not made a connection to the fault LED but am just manually pulling that input high and low on the breadboard with another wire link as required.
Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
Are yu sure that it's an OXCO? According to the manual that I have, the only option for the 5300B counter unit was option 001, which added a TXCO. The manual doesn't give any data on the Option 001 oscillator, so can't confirm that your oscillator is TXCO or OXCO. If it's a TXCO, it won't get very warm, of course, and there won't be any oven control circuitry. Is there an HP part number on the oscillator module? Cheers, Dave M. Burt I. Weiner wrote: The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
Bob, Alas, I suspect you've hit the nail on the head. I'll probably wind up replacing the oscillator with something similar that I can make work. While I've got some pretty good counters in the racks in my workshop, the 5300B is a handy little counter to schlep around for low frequency work. Beside, it's lighter than the rack mounted counters. Thanks, Burt, K6OQK From: Bob Camp kb...@n1k.org Hi If the OCXO was not heating, it would be off by about 20 to 60 Hz. It's close enough that it is getting power and heating up. If it does move when you fiddle the trimmer, that part is likely still connected. It sounds like the beast has simply aged further than it's trim range. Bob On Nov 1, 2014, at 8:39 PM, Burt I. Weiner b...@att.net wrote: The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
Bert, the normal oscillator is just a crystal. Option 001 is a TCXO, no oven. If you do not have opt 001, I would look for the second adjustment internally. Two are shown on the schematic. - Original Message - From: Burt I. Weiner b...@att.net To: time-nuts@febo.com Sent: Saturday, November 01, 2014 8:39 PM Subject: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base... The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?s earchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. ThatâÂÂs not out of the likely adjustment range on the basic crystal reference on a 5308. ItâÂÂs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
I've had a few of these over the years and option 001 is indeed a TCXO. Best bet for calibrating the TCXO is removing it from 5300B and tweak the osc on the bench Also remember these were designed as service grade counters for land mobile service not lab grade instruments. There are battery and DVM modules available for these as well This is a nice counter for radio service but it's not time nuts grade Sent from my iPhone On Nov 1, 2014, at 11:39 PM, Tom Miller tmiller11...@verizon.net wrote: Bert, the normal oscillator is just a crystal. Option 001 is a TCXO, no oven. If you do not have opt 001, I would look for the second adjustment internally. Two are shown on the schematic. - Original Message - From: Burt I. Weiner b...@att.net To: time-nuts@febo.com Sent: Saturday, November 01, 2014 8:39 PM Subject: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base... The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?s earchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. ThatâÂÂs not out of the likely adjustment range on the basic crystal reference on a 5308. ItâÂÂs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base...
HP Agilent 05341-60047 10 MHZ Oscillator Microsonics 0960-0394 HP Agilent 05341-60047 10 MHZ Oscillator Microsonics ... US $99.00 Used in Business Industrial, Electrical Test Equipment, Test Equipment View on www.ebay.com Preview by Yahoo From: Scott McGrath scmcgr...@gmail.com To: Tom Miller tmiller11...@verizon.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, November 1, 2014 10:00 PM Subject: Re: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base... I've had a few of these over the years and option 001 is indeed a TCXO. Best bet for calibrating the TCXO is removing it from 5300B and tweak the osc on the bench Also remember these were designed as service grade counters for land mobile service not lab grade instruments. There are battery and DVM modules available for these as well This is a nice counter for radio service but it's not time nuts grade Sent from my iPhone On Nov 1, 2014, at 11:39 PM, Tom Miller tmiller11...@verizon.net wrote: Bert, the normal oscillator is just a crystal. Option 001 is a TCXO, no oven. If you do not have opt 001, I would look for the second adjustment internally. Two are shown on the schematic. - Original Message - From: Burt I. Weiner b...@att.net To: time-nuts@febo.com Sent: Saturday, November 01, 2014 8:39 PM Subject: [time-nuts] UPDATE: HP 5300B - HP 5308A Counter Time Base... The closest it will adjust is -2.5 Hz of 10. MHz. This unit differs from the one in the manual in that it has a Microsonics OCXO with the adjustment on the side of the module. The oven does not feel warm but is written on the side is: Adjust at 25 Deg C, which is about 77 degrees F. The schematic associated with the oven is missing from the schematic. I suspect that the oven is either shot or not getting power. The unit will not power up with the boards separated so I'm going to have to spend some time hanging wires out the side to make measurements. Does anyone know of a schematic showing the Microsonics module and the associated circuitry for oven control? Not sure if it's worth the effort, but it would be a shame to toss it - that's against my nature. Burt, K6OQK Tom Bob, Thanks for the comments and quick reply. Tom, when I originally did a google search I did not see the site that you sent, but from your guidance I did find the manual showing the frequency adjustment and I'm letting the 5300B/5308A combination counter heat up. From a cold start it's about 6+ Hz low when compared to my house GPS reference - a DATUM 9390-52054. In a bit I'll give the thing a tweak and it should come right in as Bob suggests. I don't know the history of this counter except that the fellow that gave it to me has nothing to really compare it against nor the experience to question its accuracy. On my unit the oscillator adjustment marking is gone, but the hole for the adjustment thankfully is still there : I'll let you know how it goes - should be a simple tweak. Thanks Guys, Burt K6OQK From: Tom Miller tmiller11...@verizon.net Subject: Re: [time-nuts] HP 5300B - HP 5308A Counter Time Base Hi Bert, The service manual for the 5300B is on the keysight.com site under manuals. http://www.keysight.com/main/techSupport.jspx?s earchT=5300Bid=5300B:epsg:propageMode=OVpid=5300B:epsg:procc=USlc=eng Do you have a frequency reference (house standard) that you can use to adjust the reference in the counter? See the manual. Regards, Tom From: Burt I. Weiner b...@att.net I was recently given a HP-5300B / 5308A counter. I thought it might be handy when I'm at an AM broadcast transmitter and need to make rough frequency measurements. It turns out that at 1000 kHz it reads about 4.5 Hz high. Looking inside I'm not sure if there's a time base adjustment. I looked at the on-line manuals available and I don't find any reference to adjusting the time base frequency. Does anyone here know anything about these counters? Is there a schematic available? I'm not looking for precision, but 4.5 Hz at 1 MHz seems a tad much. Burt, K6OQK -- From: Bob Camp kb...@n1k.org Hi 4.5 Hz at 1 MHz is 4.5 ppm. ThatâÂÂs not out of the likely adjustment range on the basic crystal reference on a 5308. ItâÂÂs probably a simple tweak to get it back into calibration. Bob Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To
