Re: [time-nuts] My NTGS50AA failed
Hi Ignacio I have removed a faulty oscillator from one of these, not one of my more relaxed moments and quite amazed when the board emerged totally undamaged, but proof at least that it can be done:-) With the oscillator removed there's access to two sets of connector pads that will either accept SMA or SMB connectors and after conducting tests on the original oscillator via flying leads just soldered to the board I decided not to fit a replacement to the board after all but to fit a couple of SMB connectors to make the setup more versatile, and to avoid the possibility of having to remove another oscillator in the future:-) Another advantage of these pads is that if the board does get damaged removing the oscillator they can still be used as an alternative. The connectors take the 10MHz from the oscillator into the board and the EFC control voltage out from the board to the oscillator, now there's a surprise:-), and oscillator power can be completely external if required. From this it would seem that the reference supply from the oscillator itself is not used in practice, certainly not in the offboard case anyway. As others have suggested it seems likely your problem may not be the oscillator itself, but it still might be worth removing anyway to make testing and fault finding more straightforward. The maximum positive excursion of the NTGS50AA should be 6 volts, not 5 as you're seeing, and another indication it might be worth removing the oscillator to see how the board behaves stand alone. I've not seen what seemed to be the repeated attempts at lock that you mentioned previously, but then I wasn't even aware for a long time that the control voltage could drive below 3 volts as well as above it:-) This is my note from previous observation of my faulty unit - When first powered it brings up all LEDs and then switches to a green LED for a few seconds and then amber. It starts a self survey and acquisition process with all appearing ok, and the DAC voltage reported as 3.02 volts. Sometime later, I've seen as short as 6 minutes but as long as 12 to 15 depending on how long the oscillator has been turned off and allowed to cool, once enough satellites are being tracked, the DAC voltage starts to increase, presumably seeking to drive the oscillator frequency to 10MHz, but the frequency doesn't reach 10MHz and the DAC voltage ramps up to 6.04 volts over a period of approx 30 seconds where it remains. As the DAC voltage crosses approx 5.6 volts the Red fault LED is switched on, as opposed to green that would normally be expected to indicate all was well, and Lady Heather's OSC: report switches from Good to Bad and highlights red. Similarly Normal OSC age changes to OSC age alarm and also highlights red. --- I've attached a Lady H plot that shows this, hopefully it will get through OK. The above DAC voltages were as reported by Lady Heather but I've checked these and, when the board is working as it should be anyway, they're very close. In my case the problem described above was an oscillator that had aged beyond the upper 6 volt limit, needing approx 6.54 volts to reach 10MHz, and once removed from the board I was able to add a simple op amp level shifter to bring it back into range just to prove all else was ok, which it was, but obviously Lady H now indicated the EFC into the level shifter rather than at the oscillator itself. Whilst your problem sounds like it might not be quite such an obvious fix, removing the oscillator would open the loop and make testing both the oscillator and the board much easier, so much as it's a pain I do feel that's probably your best next step. Regards Nigel GM8PZR In a message dated 12/11/2014 02:06:54 GMT Standard Time, eb4...@cembreros.jazztel.es writes: Hi, Removing the oscillator for testing and replacing it with other if it was the culprit was my first option. I have a spare Trimble oscillator that probably came from other NTGS50AA since it still have the foam band attached, but this oscillator is really aged, it needs 7.91 V to bring it on spot and the maximum control voltage of the NTGS50AA is 5 V. I was trying to avoid removing the oscillator but probably it must be done to clarify things. Thank you, Ignacio EB4APL . El 12/11/2014 a las 2:40, Mark Sims escribió: I have seen this caused by the oscillator not responding to the EFC signal. Fixed it by swapping in a MV-89 oscillator. The oscillators used in these units don't output an oven temperature monitor signal. ___ 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
Re: [time-nuts] Second Units? KS-24361
Hi If you look at the TDev plots or a phase plot on these units, they look a lot like a Z3801. They wander 10’s or ns as they do their “thing”. While GPS out of these receivers is good to (at most) 1 ns. That’s the resolution of the sawtooth (if they are using it). That only counts if you are looking at the 1 second to 1 second RMS deltas. The “fall off by tau” rule holds for a few decades past 1 second, but it does eventually fall apart. The GPSDO will follow GPS past a point. Bob On Nov 11, 2014, at 8:55 PM, paul swed paulsw...@gmail.com wrote: Bob I will say that I am watching the noise of the pps ti in the z3811 program. Granted its been running 30 some hours now. Virtually nothing in time. My fingers are crossed it will clean up. I do like the unit quite well. Have to thank Bert for even cluing me in. So I do agree quite a nice unit. Regards Paul WB8TSL On Tue, Nov 11, 2014 at 7:42 PM, Bob Camp kb...@n1k.org wrote: Hi Here’s another way to look at the second unit - What would you pay (on an auction site) for the parts? Since there’s a warranty on the box, all would be 100% good working parts with a solid guarantee and paid shipping back: Lucent low EMI DC-DC converter “power brick” - $35 + $5 ship MTI 260 OCXO $35 + $15 ship Nice board built up with GPSDO parts $ (gotta be at least 20) + ship Metal enclosure $ (ok, it’s not that good, $5) Connectors, buffering, filtering $ something Just the two big parts in the box likely would set you back more than the cost of the second unit delivered in the US. If you are headed into a GPSDO project, the thing is a steal. Bob On Nov 10, 2014, at 1:41 AM, F. W. Bray fwb...@mminternet.com wrote: Sorry, I intended to say that this question concerns the KS-24361 units. Forgot to put that in the subject line! I have one complete setup on the way. Any thoughts as to whether it is better to get a second complete set or just go for the unit that has the GPS in it? This would be as a spare or possibly actual use. Thanks. Fred KE6CD ___ 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] 10 MHz OCXO recommendations
Sorry a few more points to mention. If for some reason I am particularly concerned about the stability of an OCXO reference I will compare it to another OCXO and on occasion to a GPSDO as well while measuring a Device Under Test. This gives me some comfort that if am looking at the performance of a particular Device Under Test that any drift in the OCXO I am using as a reference would have been detected. (It also gives me a reason to keep my stack of HP5370 and HP5335 counters running.) I don't expect this approach to give me absolute certainty of picking up drift or jumps in my reference but it does give me some comfort. While I suspect this approach would not go over very well in a commercial lab vs buying a high performance cesium standard or H Maser (: for hobby use it seems to work for me. Timelab is also useful for collecting analyzing the data from the various counters. I also trigger all the counters from the same 1pps source. I typically compare my best OCXO's to my best GPSDO on a more or less continuous basis (from a time nuts perspective it's of some interest to look at their long term drift.) From time to time I also cross check my best GPSDO against another GPSDO (: Regards Mark Spencer Sent from my iPad On 2014-11-11, at 4:26 PM, Charles Steinmetz csteinm...@yandex.com wrote: Mark wrote: I find the concept of occasionally adjusting a good OCXO which in turn is used as a reference works well for me.I have some that haven't needed adjustment for over 2 years (they are still well within one part per billion of being on frequency.) A few of us have advocated this approach on the list, and there is good reason for it. A GPSDO offers two advantages: (1) it is self-adjusting, therefore easy to own and use; and (2) it has better stability at long tau than the OCXO alone. The price you pay for those advantages is poorer stability at low tau than the OCXO alone, which can be anywhere from slight with a good design (e.g., Thunderbolt, Z3801) to shockingly bad with a bad design (including many DIY attempts). If one does not need the very best performance at long tau -- and most time-nuts do not -- a free-running OCXO that you adjust manually every now and then can be the best reference available to the average time nut. (Long tau can be anywhere from 100 seconds to several thousand seconds, depending on the particular OCXO.) Plus, not spending money on GPS discipline allows you to spend more on the OCXO to get better stability at low tau, and a more extended upper limit on low tau (say, better than GPS all the way to 2000 seconds instead of 200 seconds). Personally, I do use GPS discipline to keep my best OCXO in perpetual adjustment, but that is mostly for convenience. Usually, I turn disciplining off when I'm taking data. Only when I'm doing something where the data are averaged for longer than about 3000 seconds do I leave it on (3000 seconds is based on the stability of my particular OCXO). Remember, GPS has a well-defined stability floor, and is not better than a good OCXO at averaging times (tau) less than 100 or even 1000 seconds -- so GPS discipline cannot do anything to help the stability of a good OCXO at shorter tau than that. (Yes, it may be able to help a lousy OCXO or TCXO at lower tau -- but you can get a better OCXO than that for $20, so why bother?) There is so much focus on GPSDOs that I think many time nuts do not realize this fundamental fact. A few rules of thumb: -- An OCXO is the best low-tau reference most amateurs can afford -- GPS discipline cannot help at low tau because it is noisy -- Most of us do not need extreme stability at long tau And some general conclusions: -- Get the best OCXO you can find -- Enclose it (thermally isolated from the enclosure) -- Don't try to whip a so-so OCXO into shape with GPS discipline Finding a really good OCXO may take some effort. Some models are more likely to be really good than others (like the BVA that Mark mentioned, and some others that have been vetted in large numbers), but even then there can be large differences from sample to sample. So, one may need to sort through a number of them to find a really good one. If one doesn't have access to a clearly better oscillator for comparison, using the three-cornered hat technique with one's best oscillators is probably the best method available to the amateur time nut. Note that quartz oscillators tend to exhibit best stability if they are left on continuously, and stability may improve for a long time (months, perhaps even many months) after they are turned on, depending on how long they were off and how much trauma they received before being powered up again). The point is that GPS discipline is not always (and maybe, not usually) the best way to get the best stability possibile over the range of tau that is most important
[time-nuts] SRS TSD12
Folks, I have noted that a number of Stanford Research TSD12 Rubidium standards are available on the auction site. I searched the TN archives and the interweb and came up with little useful information. Does anyone have any information about these units? Is it a rebadged PRS-10 made for the Telecom market? The connector pinout is identical to the PRS10, at least. TIA, Shaun M ___ 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] Lady heather and fluke 910R
Hi, It is possible get any data using fluke 910R? RM ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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] SRS TSD12
Be cautious on these. Take a lesson from my idiocy; I read this email, said h atomic oscillator, and headed to eBay. Found a listing for a reasonable price, read through too quickly, and bought one... ...a non working one meant for parts. They're interspersed with the working ones and look similar so be careful! On Tuesday, November 11, 2014, Shaun Merrigan shaunmerri...@outlook.com wrote: Folks, I have noted that a number of Stanford Research TSD12 Rubidium standards are available on the auction site. I searched the TN archives and the interweb and came up with little useful information. Does anyone have any information about these units? Is it a rebadged PRS-10 made for the Telecom market? The connector pinout is identical to the PRS10, at least. TIA, Shaun M ___ 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] 10 MHz OCXO recommendations
Just to add a note on the original question : there are some brand new never used Vectron 8091s available for a reasonable price now and it's drift and jitter have been on par with my Wenzel. I am not yet set up to measure it's phase noise or other general rf characteristics but according to its cut sheet they're quite good. On Tuesday, November 11, 2014, Mark Spencer m...@alignedsolutions.com wrote: Sorry a few more points to mention. If for some reason I am particularly concerned about the stability of an OCXO reference I will compare it to another OCXO and on occasion to a GPSDO as well while measuring a Device Under Test. This gives me some comfort that if am looking at the performance of a particular Device Under Test that any drift in the OCXO I am using as a reference would have been detected. (It also gives me a reason to keep my stack of HP5370 and HP5335 counters running.) I don't expect this approach to give me absolute certainty of picking up drift or jumps in my reference but it does give me some comfort. While I suspect this approach would not go over very well in a commercial lab vs buying a high performance cesium standard or H Maser (: for hobby use it seems to work for me. Timelab is also useful for collecting analyzing the data from the various counters. I also trigger all the counters from the same 1pps source. I typically compare my best OCXO's to my best GPSDO on a more or less continuous basis (from a time nuts perspective it's of some interest to look at their long term drift.) From time to time I also cross check my best GPSDO against another GPSDO (: Regards Mark Spencer Sent from my iPad On 2014-11-11, at 4:26 PM, Charles Steinmetz csteinm...@yandex.com javascript:; wrote: Mark wrote: I find the concept of occasionally adjusting a good OCXO which in turn is used as a reference works well for me.I have some that haven't needed adjustment for over 2 years (they are still well within one part per billion of being on frequency.) A few of us have advocated this approach on the list, and there is good reason for it. A GPSDO offers two advantages: (1) it is self-adjusting, therefore easy to own and use; and (2) it has better stability at long tau than the OCXO alone. The price you pay for those advantages is poorer stability at low tau than the OCXO alone, which can be anywhere from slight with a good design (e.g., Thunderbolt, Z3801) to shockingly bad with a bad design (including many DIY attempts). If one does not need the very best performance at long tau -- and most time-nuts do not -- a free-running OCXO that you adjust manually every now and then can be the best reference available to the average time nut. (Long tau can be anywhere from 100 seconds to several thousand seconds, depending on the particular OCXO.) Plus, not spending money on GPS discipline allows you to spend more on the OCXO to get better stability at low tau, and a more extended upper limit on low tau (say, better than GPS all the way to 2000 seconds instead of 200 seconds). Personally, I do use GPS discipline to keep my best OCXO in perpetual adjustment, but that is mostly for convenience. Usually, I turn disciplining off when I'm taking data. Only when I'm doing something where the data are averaged for longer than about 3000 seconds do I leave it on (3000 seconds is based on the stability of my particular OCXO). Remember, GPS has a well-defined stability floor, and is not better than a good OCXO at averaging times (tau) less than 100 or even 1000 seconds -- so GPS discipline cannot do anything to help the stability of a good OCXO at shorter tau than that. (Yes, it may be able to help a lousy OCXO or TCXO at lower tau -- but you can get a better OCXO than that for $20, so why bother?) There is so much focus on GPSDOs that I think many time nuts do not realize this fundamental fact. A few rules of thumb: -- An OCXO is the best low-tau reference most amateurs can afford -- GPS discipline cannot help at low tau because it is noisy -- Most of us do not need extreme stability at long tau And some general conclusions: -- Get the best OCXO you can find -- Enclose it (thermally isolated from the enclosure) -- Don't try to whip a so-so OCXO into shape with GPS discipline Finding a really good OCXO may take some effort. Some models are more likely to be really good than others (like the BVA that Mark mentioned, and some others that have been vetted in large numbers), but even then there can be large differences from sample to sample. So, one may need to sort through a number of them to find a really good one. If one doesn't have access to a clearly better oscillator for comparison, using the three-cornered hat technique with one's best oscillators is probably the best method available to the amateur time nut. Note that quartz oscillators tend to exhibit best stability if
Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
It's interesting. I took the hint, and tried sin(a)*sin(b) expand and set b=a+pi/2. fun fun fun. All that's needed in theory is a mixer and a pi/2 phase shifter at 5 MHz. Probably a bunch of other stuff because of real parts :-) Minicircuits will sell you one, packaged, for about 50 rasbucknicks. Don Dave M I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
Only a small subset of QEX articles on available in digital format. This isn't one of them. We'll either need to get a copy from the author, or from a QEX subscriber. On 11/12/2014 2:34 PM, Dave M wrote: I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) ___ 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] Divide by five
In message 54614a56.4010...@rubidium.dyndns.org, Magnus Danielson writes: There used to be an academic paper on timing.com's home-page about their clock-ensemble algorithm called something like Advances in Time-Scale Algorithms. PTTI 24, Sam Steins work: http://tycho.usno.navy.mil/ptti/1992papers/Vol%2024_28.pdf There you go... I've long toyed with the idea of building ensemble clock, but never got around to it. I did some experiments based on that timing.com paper, but didn't really have enough clocks for it to be worthwhile, and the cooling in my lap couldn't cope with me turning so much kit on at the same time during summer. -- 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.
Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Article
Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Oz-in-DFW Sent: Wednesday, November 12, 2014 4:41 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle Only a small subset of QEX articles on available in digital format. This isn't one of them. We'll either need to get a copy from the author, or from a QEX subscriber. On 11/12/2014 2:34 PM, Dave M wrote: I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) ___ 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 A few more details to add: The serial com coming out of the GPS has several standard Motorola headers in it: @@Eanormal position message @@EnTRAIM / sawtooth status timing status message @@Bb Visible satellites message @@Bo UTC offset message The first two make sense for a GPSDO. The third is probably for the :SYSTEM:STATUS? display. The last one makes very little sense for a CDMA basestation GPSDO. On Nov 4, 2014, at 4:38 AM, Stewart Cobb stewart.c...@gmail.com wrote: A wiring diagram of the Z3809A cable interconnect cable was published earlier on this list. That information appears to be incorrect. The cable is actually wired pin 1 to pin 15, pin 2 to pin 14, etc. Another way to describe it is that for each wire in the cable, the pin numbers on each end of the cable add up to 16. A mated pair of these units is running in my lab with a scratch-built interconnect cable following the above rules. This scratch-built cable allowed access to the interconnect signals while the system was operating happily. No lights were lit except the green ON light on the Ref-0 unit (Z3812A, no GPS) and the yellow STBY light on the Ref-1 unit (Z3911A with GPS receiver). The following signals were observed on the interconnect (pin numbers given for the J5 interconnect socket on the Ref-1 unit): Pin 1: 9600 baud serial data (described below) Pin 1 is an open drain output. The pull up is supplied by pin 15. Pin 2: logic low (0.11V) Pin 2 is part of the negotiation process. It goes high and low as the boxes sort out who is who. It appears to be some sort of open drain with pull up arrangement. Pulling pin 2 low briefly will take the GPS unit out of standby status in a single box configuration if pin 3 is grounded. Pin 3: Ground (0.00V) Presence detect? (see below) Pin 4: logic high (4.79V) Pin 4 is also part of the “chat” process. It is not an open drain with pull up. It appears to be a legit CMOS output, possibly with a series resistor. Pin 5: inverted Motorola PPS, high (5V) for 800ms, low for 200ms Pin 5 is an open drain output. The pull up is supplied on pin 11. Pin 6: 17 / 23 dBm signal from Ref-0 unit (see below) Pin 7: logic high (4.48V) Pin 8: Ground (0.00V) Pin 9: logic low (0.11V) Pin 10: 17 / 23 dBm signal from Ref-1 unit (see below) Pin 11: inverted PPS, low 400us, high (5V) otherwise This pin is driven by pin 5 on the other end of the cable. It looks like a CMOS input with a pull up. Pin 12: logic low (0.12V) Pin 12 is part of a wired OR / open drain / pull up combination. It gets used to work out which box is doing what. Pin 13: Ground (0.00V) Pin 14: logic low (0.08V) Pin 14 may also be part of the “who is doing what” back and forth between the boxes. Pin 15: logic high (4.78V) Pins 3, 8, and 13 appear to be firmly connected to Ground. (Note that these are the three pins which are clipped short on the HP interconnect cable.) On an unpowered, disconnected box (either Ref-0 or Ref-1), pins 8 and 13 are connected to Ground (low resistance) and pin 3 is high impedance. Presumably pin 3 on each box (connected to the grounded pin 13 on the other box) is used to sense the presence of the other box and/or the interconnect cable. The timing of the PPS signal on pin 11 matches precisely the timing of the PPS signal available on pins 1 and 6 of J6 (RS422/PPS) on the active Ref-0 unit. Presumably this signal is coming across the cable from the Ref-0 unit. Note: when the system is coming up from a cold start, SatStat on the unit with the GPS receiver (Ref-1) will show [Ext 1PPS valid] in the space where it shows [GPS 1PPS valid] after the survey is complete. It appears that the Ref-1 unit timing system is locking its oscillator to the PPS coming from the Ref-0 unit during this time. The timing of the PPS signal on pin 5 matches the timing of the PPS output described in the Motorola OnCore manual. Presumably this signal is sourced by the Ref-1 unit to allow the Ref-0 unit to lock to GPS. The edges of this PPS signal look very dirty compared to the signal on pin 11. This may be an artifact of the homemade cable used for this experiment. The HP cable clearly has an overall shield (visible through the cable sheath) and may have internal coax or twisted pair for these PPS signals. When pin 5 and pin 11 are observed together, the usual GPS sawtooth pattern is evident. Someone discovered earlier that the both units will blink their green ON lights if the front-panel switch on either unit is set to 23 dBm vice the normal 17. Obviously each unit can communicate its switch status to the other unit. They use pins 6 and 10 to do that. Pin 10 (on the Ref-1 unit) is high (~5V) if the switch on the Ref-1 unit is in the 17 dBm position, and low in the 23 dBm position. Pin 6 (on the Ref-1 unit) gives the same indications for the switch on the Ref-0
Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
I believe I have a PDF copy of the article if anyone wants it. It's about 1.3 MB in size. DaveD On 11/12/2014 2:36 PM, Don Latham wrote: It's interesting. I took the hint, and tried sin(a)*sin(b) expand and set b=a+pi/2. fun fun fun. All that's needed in theory is a mixer and a pi/2 phase shifter at 5 MHz. Probably a bunch of other stuff because of real parts :-) Minicircuits will sell you one, packaged, for about 50 rasbucknicks. Don Dave M I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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] Bypass Capacitor Kit Prices
List, There has been limited response from the list for bypass caps for the HP 3586 and HP 5370. So this is what I was able to come up with: HP 3586 25ea 470uF 50 Volt Panasonic 667-EEU-FR1H471B for $25 This includes taxes, shipping to and my postage costs. HP 5370X 50ea 150uF 50V Panasonic 667-EEU-FR1H151B for $25. This includes taxes, shipping to and my postage costs. I did not include the large (expensive) input filter caps as that will be up to the individuals discretion. However I will send a complete recap list with every order. I’m setting a cutoff date of Nov. 25th for orders. Delivery will probably be mid Dec. I won’t cash your check until I ship you your parts. My address is Perry Sandeen 661 La Costa Banning, CA 92220-5317 Also if one wants one or both of the lists just for reference, please send me an original email and I’ll send you a copy. SandeenpaXXatXXyahoo.com. Regards, Perrier ___ 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] Lucent GPSDO comments
Wrote: At some point we will get into hacking the main board to switch from 15 MHz to 10 MHz. One doesn’t have to that if one uses the two IC divide by 1.5 circuit I offered the list. I specifically found it so I didn’t have to hack the innards. Wrote: The great news is the oscillator is 5 Mhz. Don’t bet the rent on that. My early units have 10 MHZ Datum oscillators. Bob’s point about getting the GPSDO’s if all cost the same is a good point. Another point. At least on the older units I have: GPSDO, Rubidium, and Crystal oscillator, the output circuitry after the 15 MHz conversion takes place is the same. So if one hacks the 10 Mhz into the chain, all one has to do is remove or bypass the 15 MHz filter before the output. Even if you don’t have the rubidium unit but have either/or GPDO or Crystal oscillator email me off list for the rubidium schematic as after the logic chips they use the same circuit. Regards, Perrier ___ 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] Electrolytic Capacitor Redux
List, Thanks to all for their comments. Wrote: The high grade aluminum electrolytics and the tantalums will look quite different on a network analyzer as you sweep them from 100 KHz up. OK. Since these of just being used for DC PS bypassing on individual boards I think I’ll be OK with the Panasonic electrolytics. Wrote: Take a look at the Aluminum Organic Polymer Electrolytics. Available in 105 °C and 125 °C. They have very low ESRs. In the milliohms. Yowza! Excellent specs but they cost more than tantalums Wrote: bought Vishay/Sprague caps. I looked at what Mouser stocked but they don’t match the capacitance values I need. My goal when it comes to huge uF caps HP uses in their PS’s is to find a kind of common(s) denominator so I can get the +10 prices. So some of my equipment my get a higher capacity and/or voltage than the OEM version. One thing I’m not going to do is use the OEM screw terminal caps because of their price. Instead I’m going to use the snap-in style and mount them using #16 solid copper wire. I checked the HP 3586 PS schematic and the are specing 40 micro-volts ripple before the regulators. Tight! Regards, Perrier SandeenpaXXatXXyahoo.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] Quad Driven Mixer 5 to 10 MHz Doubler Article
John wrote: It is a cute technique, not originated by me, but useful. Indeed it is. I designed a similar one using a quadrature hybrid splitter and level 7 mixer, and it's almost scary how well it works. It's as cute as a regenerative divide by two using a DBM. 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] Quad Driven Mixer 5 to 10 MHz Doubler Article
I also appreciate the Wenzel circuit. Not seeing the other article, I might guess that maybe it offers suppression of the original 5 MHz signal as a benefit. It seems to be the equivalent of a digital XOR circuit with one lead delayed by 90 degrees. Regards Paul WB8TSL On Wed, Nov 12, 2014 at 6:06 PM, Brian, WA1ZMS wa1...@att.net wrote: Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Oz-in-DFW Sent: Wednesday, November 12, 2014 4:41 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle Only a small subset of QEX articles on available in digital format. This isn't one of them. We'll either need to get a copy from the author, or from a QEX subscriber. On 11/12/2014 2:34 PM, Dave M wrote: I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) ___ 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 GPSDO comments
Hi The chain in the Z3810 / 3811 / 3812 Lucent boxes is *much* different than the setup in the earlier parts. The phase noise and ADEV on the Z3810’s is better than what you got on the earlier versions. That makes keeping the noise down in whatever mod you do more important. The existing 10 MHz output on the Z3810 setup is a real good example of how a seemingly simple thing can add a lot of phase noise and even mess up ADEV. I don’t think the 15 MHz is used for much of anything in the Z3810. That could be wrong, but I can’t see where it is needed based on poking around a little. The 15 MHz buffer appears to be quiet and puts out a lot of power. Using it for 10 MHz would give you a *lot* of 10 MHz signal to play with. IF the mods are simple it’s an attractive solution. If it involves swapping out 30 parts - not so much. Bob On Nov 12, 2014, at 5:50 PM, Perry Sandeen via time-nuts time-nuts@febo.com wrote: Wrote: At some point we will get into hacking the main board to switch from 15 MHz to 10 MHz. One doesn’t have to that if one uses the two IC divide by 1.5 circuit I offered the list. I specifically found it so I didn’t have to hack the innards. Wrote: The great news is the oscillator is 5 Mhz. Don’t bet the rent on that. My early units have 10 MHZ Datum oscillators. Bob’s point about getting the GPSDO’s if all cost the same is a good point. Another point. At least on the older units I have: GPSDO, Rubidium, and Crystal oscillator, the output circuitry after the 15 MHz conversion takes place is the same. So if one hacks the 10 Mhz into the chain, all one has to do is remove or bypass the 15 MHz filter before the output. Even if you don’t have the rubidium unit but have either/or GPDO or Crystal oscillator email me off list for the rubidium schematic as after the logic chips they use the same circuit. Regards, Perrier ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
As a subscriber to QEX I saw this article but thought that the bi-phase rectifier was a lot easier and has be well characterised by the time-nuts experts. Now it has shown up here I would be interested to hear from those experimenting how badly the NE602 performs compared with a passive DBM for nuts-style applications :-)) I have a pile of kit with 5MHz VCXOs (Racal and Marconi) including an excellent GPSDO by Rapco. Alan G3NYK - Original Message - From: Dave Daniel kc0...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, November 12, 2014 10:36 PM Subject: Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle I believe I have a PDF copy of the article if anyone wants it. It's about 1.3 MB in size. DaveD On 11/12/2014 2:36 PM, Don Latham wrote: It's interesting. I took the hint, and tried sin(a)*sin(b) expand and set b=a+pi/2. fun fun fun. All that's needed in theory is a mixer and a pi/2 phase shifter at 5 MHz. Probably a bunch of other stuff because of real parts :-) Minicircuits will sell you one, packaged, for about 50 rasbucknicks. Don Dave M I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Article
Just a few days ago, I ordered parts to build a couple of the Wenzel 2-diode doublers, described in the same article as your full-wave diode doubler, just in time to discover them on Ebay (via slow boat from China), item# 171511157159. I inspected the components and layout in the picture in the listing, and it certainly looks like the Wenzel FWB doubler. At $9.99 USD, the price is cheap enough, especially since you get SMA connectors on both ends. Might have to do a bit of solder work on the SMA connectors if you want to put it into a little box. The listing on the doubler on Ebay says that the low end is 10MHz, but I'll bet that it will get down to 5MHz quite easily If there's any trouble handling a 5MHz input, you could easily use a lower frequency ferrite for the balun and make it work. As you suggest, a BPF on the output and maybe a bit of amplification to get the level up to a usable level should get you a fairly clean 10 MHz. Dave M Brian, WA1ZMS wrote: Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 ___ 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] My NTGS50AA failed
Charles, Thank you, I found this very enlightening. Now I have to find the 9.7 KHz pulses, no luck so far. Best regards, Ignacio El 12/11/2014 a las 7:34, Charles Steinmetz escribió: Ignacio wrote: I'm not very sure that the DAC is working, I suppose that the unit doesn't measure the DAC output, it reports the DAC commands. My voltage figures is what LH reports (so the NTGS50AA reports, probably what it is trying to do), but the frequency control pin of the oscillator is stuck at 5.02 V regardless of the supposed (intended) DAC output, it does not move at all. One more thing that could be helpful -- on Nov. 2, 2013 Stewart Cobb posted a description of the DAC operation for a Trimble Thunderbolt (Thunderbolt tuning DAC theory of operation). On Jan. 5, 2014 someone (no name) posted further information on the same thread re: the Trimble/Nortel 45k. You can find both posts in the list archives (follow the link at the bottom of this post, then click time-nuts Archives on the list home page). 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
I'm a member, and the article is not there -- just the Excel spreadsheet and a Word document of the parts list. Too bad, I have a handful of 5 MHzx TCXOs. I may have hardcopy of the issue, will have to dig for it. Jim wb4...@amsat.org On 11/12/2014 3:34 PM, Dave M wrote: I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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. --- 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] My NTGS50AA failed
Hi Nigel, Thank you for the suggestions, I was trying to avoid the OCXO removal but I think that now it must be done. I was also playing with the idea of populating the connectors so an OCXO exchange could be easily made, this makes possible to try various oscillators. Meanwhile I has been probing and measuring a lot of points and by chance I found a very interesting thing: Probing TP33 (which is close to the Trimble chip (U2) and directly connected to pin 76) there is a 1PPS, 10 us wide signal. I've checked it and appears to be synchronous with the 1/2 PPS output so maybe it can be routed to an output, probably I'll replace the 1/2 PPS with it, using the existing drive circuit and connector since it is very straightforward. My only concern is if this signal only is there during the anomalous condition that I have now, I have to retest it after fixing it. I had asked several times if anybody had located a 1PPS signal on these units, but the responses were negative and I had not probed systematically the board before. Also I'm taking notes of the signals found and I'll try to make a partial schematic at least with the EFC circuitry. When I fix it I'll clean the notes and figures and I'll upload it to some place. Best regards, Ignacio El 12/11/2014 a las 11:47, GandalfG8--- via time-nuts escribió: Hi Ignacio I have removed a faulty oscillator from one of these, not one of my more relaxed moments and quite amazed when the board emerged totally undamaged, but proof at least that it can be done:-) With the oscillator removed there's access to two sets of connector pads that will either accept SMA or SMB connectors and after conducting tests on the original oscillator via flying leads just soldered to the board I decided not to fit a replacement to the board after all but to fit a couple of SMB connectors to make the setup more versatile, and to avoid the possibility of having to remove another oscillator in the future:-) Another advantage of these pads is that if the board does get damaged removing the oscillator they can still be used as an alternative. The connectors take the 10MHz from the oscillator into the board and the EFC control voltage out from the board to the oscillator, now there's a surprise:-), and oscillator power can be completely external if required. From this it would seem that the reference supply from the oscillator itself is not used in practice, certainly not in the offboard case anyway. As others have suggested it seems likely your problem may not be the oscillator itself, but it still might be worth removing anyway to make testing and fault finding more straightforward. The maximum positive excursion of the NTGS50AA should be 6 volts, not 5 as you're seeing, and another indication it might be worth removing the oscillator to see how the board behaves stand alone. I've not seen what seemed to be the repeated attempts at lock that you mentioned previously, but then I wasn't even aware for a long time that the control voltage could drive below 3 volts as well as above it:-) This is my note from previous observation of my faulty unit - When first powered it brings up all LEDs and then switches to a green LED for a few seconds and then amber. It starts a self survey and acquisition process with all appearing ok, and the DAC voltage reported as 3.02 volts. Sometime later, I've seen as short as 6 minutes but as long as 12 to 15 depending on how long the oscillator has been turned off and allowed to cool, once enough satellites are being tracked, the DAC voltage starts to increase, presumably seeking to drive the oscillator frequency to 10MHz, but the frequency doesn't reach 10MHz and the DAC voltage ramps up to 6.04 volts over a period of approx 30 seconds where it remains. As the DAC voltage crosses approx 5.6 volts the Red fault LED is switched on, as opposed to green that would normally be expected to indicate all was well, and Lady Heather's OSC: report switches from Good to Bad and highlights red. Similarly Normal OSC age changes to OSC age alarm and also highlights red. --- I've attached a Lady H plot that shows this, hopefully it will get through OK. The above DAC voltages were as reported by Lady Heather but I've checked these and, when the board is working as it should be anyway, they're very close. In my case the problem described above was an oscillator that had aged beyond the upper 6 volt limit, needing approx 6.54 volts to reach 10MHz, and once removed from the board I was able to add a simple op amp level shifter to bring it back into range just to prove all else was ok, which it was, but obviously Lady H now indicated the EFC into the level shifter rather than at the oscillator itself. Whilst your problem sounds like it might not be quite such an obvious
Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Article
Looked it up and pretty amazing. Can't really say how well the ferrite will go down to 5. It should. Paul WB8TSL On Wed, Nov 12, 2014 at 7:22 PM, Dave M dgmin...@mediacombb.net wrote: Just a few days ago, I ordered parts to build a couple of the Wenzel 2-diode doublers, described in the same article as your full-wave diode doubler, just in time to discover them on Ebay (via slow boat from China), item# 171511157159. I inspected the components and layout in the picture in the listing, and it certainly looks like the Wenzel FWB doubler. At $9.99 USD, the price is cheap enough, especially since you get SMA connectors on both ends. Might have to do a bit of solder work on the SMA connectors if you want to put it into a little box. The listing on the doubler on Ebay says that the low end is 10MHz, but I'll bet that it will get down to 5MHz quite easily If there's any trouble handling a 5MHz input, you could easily use a lower frequency ferrite for the balun and make it work. As you suggest, a BPF on the output and maybe a bit of amplification to get the level up to a usable level should get you a fairly clean 10 MHz. Dave M Brian, WA1ZMS wrote: Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Article
Hi The Wenzel doubler has a bit of “stuff” in the middle of the bridge. It’s tuned a bit to give it best performance at a specific frequency. It’s not narrowband, but it is not a 2:1 bandwidth. Bob On Nov 12, 2014, at 7:22 PM, Dave M dgmin...@mediacombb.net wrote: Just a few days ago, I ordered parts to build a couple of the Wenzel 2-diode doublers, described in the same article as your full-wave diode doubler, just in time to discover them on Ebay (via slow boat from China), item# 171511157159. I inspected the components and layout in the picture in the listing, and it certainly looks like the Wenzel FWB doubler. At $9.99 USD, the price is cheap enough, especially since you get SMA connectors on both ends. Might have to do a bit of solder work on the SMA connectors if you want to put it into a little box. The listing on the doubler on Ebay says that the low end is 10MHz, but I'll bet that it will get down to 5MHz quite easily If there's any trouble handling a 5MHz input, you could easily use a lower frequency ferrite for the balun and make it work. As you suggest, a BPF on the output and maybe a bit of amplification to get the level up to a usable level should get you a fairly clean 10 MHz. Dave M Brian, WA1ZMS wrote: Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 ___ 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] Efratom/Datum Starloc II
I'm dusting off one of my GPSDO here, and find that I do not have the manual or the software for this Efratom/Datum Starloc II. With the Datum/Efratom/Symmetricom/Microsemi transitions (I may have missed one or two...) I don't know if any info is even still available from Microsemi. Little is to be found elsewhere on the web. This unit was mentioned once or twice in the past on the list, but doesn't seem to have been too popular. Thing is, it appears to be a Thunderbolt clone (more or less) as TBoltMon will talk to it. Lady Heather on the other hand, will crash or hang and makes the Starloc hang too. It quits sending packets and refuses to respond to further input, requiring a power cycle. I havent traced which packet is killing it yet though (using 3.12 version). Does anyone have any docs, software, or other info? I would much appreciate it. Thanks! Regards, Paul - K9MR ___ 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] My NTGS50AA failed
Hi It seems reasonable that there is a 1 pps somewhere on the board. The big question is if it’s the output of the GPS receiver or the output of the OCXO after division. Bob On Nov 12, 2014, at 8:10 PM, EB4APL eb4...@cembreros.jazztel.es wrote: Hi Nigel, Thank you for the suggestions, I was trying to avoid the OCXO removal but I think that now it must be done. I was also playing with the idea of populating the connectors so an OCXO exchange could be easily made, this makes possible to try various oscillators. Meanwhile I has been probing and measuring a lot of points and by chance I found a very interesting thing: Probing TP33 (which is close to the Trimble chip (U2) and directly connected to pin 76) there is a 1PPS, 10 us wide signal. I've checked it and appears to be synchronous with the 1/2 PPS output so maybe it can be routed to an output, probably I'll replace the 1/2 PPS with it, using the existing drive circuit and connector since it is very straightforward. My only concern is if this signal only is there during the anomalous condition that I have now, I have to retest it after fixing it. I had asked several times if anybody had located a 1PPS signal on these units, but the responses were negative and I had not probed systematically the board before. Also I'm taking notes of the signals found and I'll try to make a partial schematic at least with the EFC circuitry. When I fix it I'll clean the notes and figures and I'll upload it to some place. Best regards, Ignacio El 12/11/2014 a las 11:47, GandalfG8--- via time-nuts escribió: Hi Ignacio I have removed a faulty oscillator from one of these, not one of my more relaxed moments and quite amazed when the board emerged totally undamaged, but proof at least that it can be done:-) With the oscillator removed there's access to two sets of connector pads that will either accept SMA or SMB connectors and after conducting tests on the original oscillator via flying leads just soldered to the board I decided not to fit a replacement to the board after all but to fit a couple of SMB connectors to make the setup more versatile, and to avoid the possibility of having to remove another oscillator in the future:-) Another advantage of these pads is that if the board does get damaged removing the oscillator they can still be used as an alternative. The connectors take the 10MHz from the oscillator into the board and the EFC control voltage out from the board to the oscillator, now there's a surprise:-), and oscillator power can be completely external if required. From this it would seem that the reference supply from the oscillator itself is not used in practice, certainly not in the offboard case anyway. As others have suggested it seems likely your problem may not be the oscillator itself, but it still might be worth removing anyway to make testing and fault finding more straightforward. The maximum positive excursion of the NTGS50AA should be 6 volts, not 5 as you're seeing, and another indication it might be worth removing the oscillator to see how the board behaves stand alone. I've not seen what seemed to be the repeated attempts at lock that you mentioned previously, but then I wasn't even aware for a long time that the control voltage could drive below 3 volts as well as above it:-) This is my note from previous observation of my faulty unit - When first powered it brings up all LEDs and then switches to a green LED for a few seconds and then amber. It starts a self survey and acquisition process with all appearing ok, and the DAC voltage reported as 3.02 volts. Sometime later, I've seen as short as 6 minutes but as long as 12 to 15 depending on how long the oscillator has been turned off and allowed to cool, once enough satellites are being tracked, the DAC voltage starts to increase, presumably seeking to drive the oscillator frequency to 10MHz, but the frequency doesn't reach 10MHz and the DAC voltage ramps up to 6.04 volts over a period of approx 30 seconds where it remains. As the DAC voltage crosses approx 5.6 volts the Red fault LED is switched on, as opposed to green that would normally be expected to indicate all was well, and Lady Heather's OSC: report switches from Good to Bad and highlights red. Similarly Normal OSC age changes to OSC age alarm and also highlights red. --- I've attached a Lady H plot that shows this, hopefully it will get through OK. The above DAC voltages were as reported by Lady Heather but I've checked these and, when the board is working as it should be anyway, they're very close. In my case the problem described above was an oscillator that had aged beyond the upper 6 volt limit, needing approx 6.54 volts to reach 10MHz, and once removed from
Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Article
Hi In the “as wired” configuration, that looks more like a full wave doubler than the full Wenzel tuned multiplier. You may be able to re-wire it for the full circuit. Bob On Nov 12, 2014, at 8:20 PM, paul swed paulsw...@gmail.com wrote: Looked it up and pretty amazing. Can't really say how well the ferrite will go down to 5. It should. Paul WB8TSL On Wed, Nov 12, 2014 at 7:22 PM, Dave M dgmin...@mediacombb.net wrote: Just a few days ago, I ordered parts to build a couple of the Wenzel 2-diode doublers, described in the same article as your full-wave diode doubler, just in time to discover them on Ebay (via slow boat from China), item# 171511157159. I inspected the components and layout in the picture in the listing, and it certainly looks like the Wenzel FWB doubler. At $9.99 USD, the price is cheap enough, especially since you get SMA connectors on both ends. Might have to do a bit of solder work on the SMA connectors if you want to put it into a little box. The listing on the doubler on Ebay says that the low end is 10MHz, but I'll bet that it will get down to 5MHz quite easily If there's any trouble handling a 5MHz input, you could easily use a lower frequency ferrite for the balun and make it work. As you suggest, a BPF on the output and maybe a bit of amplification to get the level up to a usable level should get you a fairly clean 10 MHz. Dave M Brian, WA1ZMS wrote: Gentlemen- I have my paper copy in front of me with the original article. I am not certain that I can just scan it and send it around due to ARRL Author copyright matters. But I am willing to scan it. With all due respect to John, K6IQL the author who spent much time on his design..I would opine that an equivalent doubler could be made from the Wenzel doubler circuits that are on the Wenzel web page and from first-hand experience...I used such a 5-to-10 MHz doubler for all of my amateur radio projects up through 403GHz. The K6IQL design, in brief, splits the 5MHz signal into two paths. One passes to the LO port of a Double Balanced mixer, while the second path goes through a 90-deg phase shift network and into the RF port of that JMS-1MH mixer. The output is taken from the IF port. The output is then buffered filtered. He spent much design effort on the 90-deg phase shift network to keep it all temp stable. Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. -Brian, WA1ZMS/4 ___ 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
I mentioned my article because it is a useful technique. The major virtues are that it is analog, thus possibly a lot less noise than an XOR, it is easy, and the fundamental and all of the odd harmonics are well suppressed. I make no claim that it is better or cheaper, or is a prettier color than some other techniques. So what! The snarky comments about this or that other method are fine but really do discourage someone from submitting to this list. You see I do not really care to design the cheapest, or ugliest, or marginal? gizmos. Rather I do that which interests me and? I can buy/do pretty well what I please. If I? think someone may find it of interest I will publish it. After you have prepared a 50 page draft with a couple of dozen photos, graphs, and reams of test data and then get it published, you may gain my respect. But the one line I prefer the Black Phantom Doubler from the Mythical Device Corp, because it only cost 78 cents is not contributory to the advancement of anything. Best regards and lets be nice now. -73 john roos k6iql ___ 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] Divide by five
Hi On Nov 12, 2014, at 5:24 PM, Poul-Henning Kamp p...@phk.freebsd.dk wrote: In message 54614a56.4010...@rubidium.dyndns.org, Magnus Danielson writes: There used to be an academic paper on timing.com's home-page about their clock-ensemble algorithm called something like Advances in Time-Scale Algorithms. PTTI 24, Sam Steins work: http://tycho.usno.navy.mil/ptti/1992papers/Vol%2024_28.pdf There are a raft of papers from the 60’s and 70’s talking about the paper clocks and their initial efforts to turn them into software versions of the paper tables. There you go... I've long toyed with the idea of building ensemble clock, but never got around to it. I did some experiments based on that timing.com paper, but didn't really have enough clocks for it to be worthwhile, and the cooling in my lap couldn't cope with me turning so much kit on at the same time during summer. It has occurred to me that running 100 Rubidiums at 15W each might get the electric meter spinning a bit fast. It’s also not really very clear how to test the result without building two or three of them. Keeping three batches of 100 Rb’s from talking to each other on a thermal basis might be even more difficult than the basic issues around a 4.5KW load plus cooling 24 hours a day. Lots to think about. Bob -- 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 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] Quad Driven Mixer 5 to 10 MHz Doubler Article
Brian wrote: Personally, I'm lazy and like the Wenzel full wave rectifier design with a nice BPF on the output to obtain a clean 10MHz. The advantage of the multiplier circuit is that the signal straight out of the mixer has excellent harmonic and 5MHz suppression. In my circuit with the quadrature hybrid, 5MHz feedthrough is less than -45dBc and the most prominent harmonic (30MHz) is less than -30dBc. The visible spurs are all odd harmonics of the 10MHz output, so the signal is symmetrical and for many uses does not need any further filtering. I generally use a 2-pole active filter that reduces the 30MHz to better than -55dBc, and if I need to get crazy I can add a simple series LC at the output to get the 30MHz below -70dBc. This strategy minimizes the risk of temperature-dependent phase shift from the steep filter that would be necessary to reduce the spurs to those levels following a diode doubler. 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] Quad Driven Mixer 5 to 10 MHz Doubler Atricle
I digitized the first 2011 article to hand, the one in Jan-Feb; it's a smaller article, and not as elegant as the later one. Anyone interested can email me off-list. You're allowed to have a copy for your own use, just can't re-publish. Don Jim Sanford I'm a member, and the article is not there -- just the Excel spreadsheet and a Word document of the parts list. Too bad, I have a handful of 5 MHzx TCXOs. I may have hardcopy of the issue, will have to dig for it. Jim wb4...@amsat.org On 11/12/2014 3:34 PM, Dave M wrote: I am able to download the files associated with the article, but not the article itself. Guess I need to be a paying member to get the article. The only files in the download are the XLS file for calculating the filter values, and the parts list. It's at http://www.arrl.org/qexfiles in the year 2011 listings, filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency Standard to 10 MHz with a Low Spurious Frequency Doubler Dave M John C. Roos via time-nuts wrote: Several list members contacted me expressing interest in the article. None of them were able to download much or anything from the ARRL QEX web site. That includes me and other ARRL members. I am working the issue with one call to ARRL so far today. I will contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang in there. It is a cute technique, not originated by me, but useful. Right now I have to get the ARRL FMT done first. -73 john c roos k6iql ___ 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. --- 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. -- 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.
