Re: [time-nuts] 1900kHz radiolcation testing on east coast US?
On 8 December 2014 at 07:24, Chris Wilson ch...@chriswilson.tv wrote: This is audible here in the UK and elicited many comments on 160 meters last night. Seen as oblique striations on SDR receiver displays and audible as a clicking sound. What the devil is it? Best Regards, Chris Wilson. A mutation of the woodpecker. Dave ___ 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] 1900kHz radiolcation testing on east coast US?
Is the signal still there? I looked here on the West Coast - don't really see anything. Thanks, John AJ6BC On Mon, Dec 8, 2014 at 12:42 AM, Dr. David Kirkby (Kirkby Microwave Ltd) drkir...@kirkbymicrowave.co.uk wrote: On 8 December 2014 at 07:24, Chris Wilson ch...@chriswilson.tv wrote: This is audible here in the UK and elicited many comments on 160 meters last night. Seen as oblique striations on SDR receiver displays and audible as a clicking sound. What the devil is it? Best Regards, Chris Wilson. A mutation of the woodpecker. Dave ___ 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] 1900kHz radiolcation testing on east coast US?
Wouldn't you know it - about the time I sent that last e-mail - I am getting something in the 1.915 MHz range right now - and you could say this is around 4 Hz or so - I am trying to see if I can get a match on any modulation type - but nothing so far. Definitely wider though. Regards, John AJ6BC On Mon, Dec 8, 2014 at 2:05 AM, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Is the signal still there? I looked here on the West Coast - don't really see anything. Thanks, John AJ6BC On Mon, Dec 8, 2014 at 12:42 AM, Dr. David Kirkby (Kirkby Microwave Ltd) drkir...@kirkbymicrowave.co.uk wrote: On 8 December 2014 at 07:24, Chris Wilson ch...@chriswilson.tv wrote: This is audible here in the UK and elicited many comments on 160 meters last night. Seen as oblique striations on SDR receiver displays and audible as a clicking sound. What the devil is it? Best Regards, Chris Wilson. A mutation of the woodpecker. Dave ___ 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] 1900kHz radiolcation testing on east coast US?
this signal is being heard all across the eastern part of North America and there are reports from at least as far west as Montana. I can hear it during the day but at a very low level. Night time levels are much stronger. cheers, Graham ve3gtc FN25ig near Ottawa Canada On 2014-12-07 19:09, Bob Camp wrote: Hi 120 Hz sub structure suggests a (much lower power) switching power supply run amok. I certainly would not design a system that would have virtually no immunity to power line noise ….. Bob On Dec 7, 2014, at 6:28 PM, Tim Shoppa tsho...@gmail.com wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Tim N3QE ___ 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] 1900kHz radiolcation testing on east coast US?
Radiolocation may be a bit misleading. Some first thought that this was CODAR but it is not, at least not what I am familiar with but it may be another variation of an ocean surface wave RADAR type of system but it is certainly not like one I have heard before. cheers, Graham ve3gtc On 2014-12-07 20:03, paul swed wrote: Not aware of any testing plus it makes no sense these days. LORAN long ago abandoned and was in that range and Loran C in the US dead. UrsaNav has been quite for quite a while. Regards Paul WB8TSL On Sun, Dec 7, 2014 at 7:09 PM, Bob Camp kb...@n1k.org wrote: Hi 120 Hz sub structure suggests a (much lower power) switching power supply run amok. I certainly would not design a system that would have virtually no immunity to power line noise ….. Bob On Dec 7, 2014, at 6:28 PM, Tim Shoppa tsho...@gmail.com wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Tim N3QE ___ 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] 1900kHz radiolcation testing on east coast US?
Hello, Can someone please post a *.wav file of what it sounds like provided you have an SDR set-up? If you need someplace to post - please send the file to me offlist and I'll put it on either an ftp site or http. I am not so convinced what I saw wasn't noise or some stations from China transmitting - which I have seen in the 160m band lately. I got an AM band tonight also that was stomping all over ~ 3.87 MHz. Thanks! John AJ6BC On Mon, Dec 8, 2014 at 2:30 AM, Graham planoph...@aei.ca wrote: Radiolocation may be a bit misleading. Some first thought that this was CODAR but it is not, at least not what I am familiar with but it may be another variation of an ocean surface wave RADAR type of system but it is certainly not like one I have heard before. cheers, Graham ve3gtc On 2014-12-07 20:03, paul swed wrote: Not aware of any testing plus it makes no sense these days. LORAN long ago abandoned and was in that range and Loran C in the US dead. UrsaNav has been quite for quite a while. Regards Paul WB8TSL On Sun, Dec 7, 2014 at 7:09 PM, Bob Camp kb...@n1k.org wrote: Hi 120 Hz sub structure suggests a (much lower power) switching power supply run amok. I certainly would not design a system that would have virtually no immunity to power line noise ….. Bob On Dec 7, 2014, at 6:28 PM, Tim Shoppa tsho...@gmail.com wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/ 1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Tim N3QE ___ 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] Fw: GPS, NTP, and Cisco routers...
Dear Mark, Thanks for the file. In fact the 7204 IOS was work for 10year+ when it pair w/ TimesSource3600 PRS. a few month before the TS3600 was dead and I replace it w/ TS3550. So I was wondering, is there something difference in TOD between TS3600 TS3550. Any suggestion?, I already replace 7204 and try a newer ISO ( from c7200-is-mz.122-11.T.bin to c7200-ipbasek9-mz.122-33.SRD8.bin) Thanks Bob Chan On Mon, Dec 8, 2014 at 6:57 AM, Mark Allwright mark.allwri...@shaw.ca wrote: -Original Message- From: Mark Allwright Sent: Sunday, December 07, 2014 3:47 PM To: time-nuts@febo.com Subject: Re: [time-nuts] GPS, NTP, and Cisco routers... Hi Bob. Here is a copy of the application note. I stopped using Cisco routers as my primary NTP sources some time ago (years). Did you try some other/older Cisco IOS versions on your 7204? Regards. Mark. -- Mark Allwright, VE6NTP -Original Message- From: Bob Chan Sent: Friday, December 05, 2014 5:51 PM To: time-nuts@febo.com ; mark.allwri...@bell.ca Subject: [time-nuts] GPS, NTP, and Cisco routers... Dear all, Do any one still using Cisco 7200 as NTP master? and get ref clock from Microsemi GPS TOD via Aux port I used to have a TimeSource3600 to feed TOD to a Cisco7204VXR, but the TS3600 was dead, and I TimeSource3550 was installed. But I found the 7204 cannot get a reliable PPS from the TS3550. In 7204, I use below command: line aux 0 ntp refclock telecom-solutions pps cts stratum 0 no exec transport input all stopbits 1 line vty 0 4 exec-timeout 20 0 ! ntp access-group query-only 95 ntp access-group peer 96 ntp access-group serve 97 ntp access-group serve-only 98 ntp master In TS3550, I set the TOD format to Cisco, and a TOD converter was installed. The 7204 can sync to GPS after a reboot. but after some time (form min. to an hour) it will lost sync to GPS and said Bad Time or No PPS signal in sh ntp asso detail and sh line aux wil indicate alot of noise overrun 7204 sh ntp ass de 127.127.7.1 configured, our_master, sane, valid, stratum 7 ref ID 127.127.7.1, time D8212701.14C20B50 (12:28:49.081 HKT Thu Nov 27 2014) our mode active, peer mode passive, our poll intvl 64, peer poll intvl 64 root delay 0.00 msec, root disp 0.00, reach 377, sync dist 0.015 delay 0.00 msec, offset 0. msec, dispersion 0.02 precision 2**18, version 3 org time D8212701.14C20B50 (12:28:49.081 HKT Thu Nov 27 2014) rcv time D8212701.14C20B50 (12:28:49.081 HKT Thu Nov 27 2014) xmt time D8212701.14C1C10F (12:28:49.081 HKT Thu Nov 27 2014) filtdelay = 0.000.000.000.000.000.000.00 0.00 filtoffset =0.000.000.000.000.000.000.00 0.00 filterror = 0.020.991.972.943.924.905.87 6.85 Reference clock status: Running normally Timecode: --More-- 127.127.6.1 configured, insane, invalid, unsynced, stratum 0 ref ID .GPS., time . (08:00:00.000 HKT Mon Jan 1 1900) our mode active, peer mode unspec, our poll intvl 64, peer poll intvl 64 root delay 0.00 msec, root disp 0.00, reach 0, sync dist 103.516 delay 0.00 msec, offset 0. msec, dispersion 16000.00 precision 2**20, version 3 org time . (08:00:00.000 HKT Mon Jan 1 1900) rcv time . (08:00:00.000 HKT Mon Jan 1 1900) xmt time D8212733.14C1CF13 (12:29:39.081 HKT Thu Nov 27 2014) filtdelay = 0.000.000.000.000.000.000.00 0.00 filtoffset =0.000.000.000.000.000.000.00 0.00 filterror = 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 Reference clock status: No PPS signal Timecode: *,A,56989,14/11/27,04:29:47,+00.0,0,22N22.238,114E07.820,+0095 sh lin aux 0 Tty Typ Tx/RxA Modem Roty AccO AccI Uses Noise Overruns Int *1 AUX 9600/9600 -- --- 0 581 1/799854 - Line 1, Location: , Type: Length: 24 lines, Width: 80 columns Baud rate (TX/RX) is 9600/9600, no parity, 1 stopbits, 8 databits Status: Ready, Active, Modem Signals Polled Capabilities: EXEC Suppressed, NTP Reference Clock, PPS Reference Clock Modem state: Ready Modem hardware state: CTS* noDSR DTR RTS Special Chars: Escape Hold Stop Start Disconnect Activation ^^xnone - - none Timeouts: Idle EXECIdle Session Modem Answer Session Dispatch 00:10:00nevernone not set Idle Session Disconnect Warning never Login-sequence User Response 00:00:30 Autoselect Initial Wait not set Modem type is unknown. Session limit is not set. Time since activation: never Editing is enabled. History is enabled, history size is 10. DNS resolution in show
Re: [time-nuts] Beaglebone NTP server
It can be but suffers from enough jitter to be unusable. All current BBB out of the box kernels have PPS-gpio. Google PPS gpio DTS bbb. Enjoy :-) On Sunday, December 7, 2014, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Dec 7, 2014 at 12:09 PM, folkert folk...@vanheusden.com javascript:; wrote: On my rpi the jitter is between 2 and 10us iirc but it is a while since I tested it. A quick peak shows me currently 3us jitter. Not bad for a userspace solution imho. Really? The PPS to GPIO interface is handles in user space? It is not interrupt driven? In the implementations I've seen the critical real time work is done inside the PPS interrupt handler and then of course ntpd runs in userland and can take as much time as it needs -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com javascript:; 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] tcxo
Hi The piles of this are hidden under the piles of that which are somewhere behind the boxes of those…. Bob On Dec 7, 2014, at 9:09 PM, Tom Miller tmiller11...@verizon.net wrote: Bob, if you are like me, you probably don't know where they all are, even if you wanted to count them. :) - Original Message - From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, December 07, 2014 8:51 PM Subject: Re: [time-nuts] tcxo Hi On Dec 7, 2014, at 8:14 PM, Hal Murray hmur...@megapathdsl.net wrote: albertson.ch...@gmail.com said: The very first thing you need to do is figure out what your requirements are. Except that this is time-nuts, so the only requirement for some of us is having fun. The original post really gave no information about what the objective is. In the context of that post (Arduino’s etc), it’s a bit hard to guess what is being attempted. With OCXO’s on the surplus market at $20 sort of prices, fiddling with a TCXO may not make much sense. That goes double if there is also a lack of measurement capability. Buying a $150 GPSDO and a $500 counter only to check your “I saved $15” TCXO is probably not a bargain, or a good use of time. Even a cheap OCXO is likely to blow away a “worked over” TCXO for stability. No don’t ask how many counters and GPSDO’s I have …. it would take *far* to long to count all of them…Then there’s all the TCXO’s and OCXO’s …. Bob But yes, you are correct in that thinking about the big picture is a good idea. -- 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. ___ 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] Did a member of time-nuts buy this?
HI On Dec 7, 2014, at 4:52 PM, Gregory Maxwell gmaxw...@gmail.com wrote: On Sun, Dec 7, 2014 at 7:03 PM, Bob Camp kb...@n1k.org wrote: Of the $20K to $30K that a new tube costs, I doubt the material and basic assembly adds up to over $5K. The rest of the cost is the final assembly / test / yield / re-test / tooling / labor. That’s doing them in as high a volume as anybody does them. You will need either a couple of H-Masers or a set of Cs’s running and in good condition simply to make sure you got them put together right …. I'm sure that assembly/test/yield/re-test/tooling/labor are all killers, but why the comment on h-masers? You need a test reference that’s “better than” the thing you are testing. CS beam standards are largely self-calibrating, thats why they can be primary references. It’s the “largely” part that gets you. They don’t get to this or that ADEV level due to primary characteristics. For checking against systemic error you might want a CS ensemble, but everyone has access to one of those for long term measurement via GPS. Checking things like mag field against a 24 hour time frame probably isn’t very efficient. It’s also going to be to be tough to keep calibrated. 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] 10MHz LTE-Lite - PPS accuracy?
On the 10MHz LTE-Lite, how far out from true UTC would the PPS be expected to be? It seems to be about 200+ ns late on my unit, although it is much more stable than a typical GPS/PPS produces. Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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 LTE-Lite - PPS accuracy?
Hi On *most* GPSDO’s, the simple answer is “there is a cable delay adjustment to align it”. Without some sort of reliable representation of UTC (at the ns level) it’s tough to measure. If you happen to live at USNO or NIST, you can access that sort of timing. For the rest of us - not so easy. The NIST two way GPS “modem” setup is about the only practical method that I know of. The PPS out of any GPSDO will be much lower jitter than the pps from a normal GPS module. Bob On Dec 8, 2014, at 7:17 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: On the 10MHz LTE-Lite, how far out from true UTC would the PPS be expected to be? It seems to be about 200+ ns late on my unit, although it is much more stable than a typical GPS/PPS produces. Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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 LTE-Lite - PPS accuracy?
What is the source of the 1 PPS you are comparing against? I compared my LTE-Lite to an old Thunderbolt (original model, single 24 V input with internal DC to DC converters, Piezo oscillator). At the time, the Thunderbolt had been running for a few months, while the LTE-Lite had been running for a week or so. Antennas were sitting on the window ledge of a west-facing window, so relatively poor sky coverage. I connected the PPS outputs from the two GPSDOs to two channels of a digital scope and left it running in accumulate mode. A couple of the resulting displays are attached below (I hope). Yellow trace is the Thunderbolt PPS, also the trigger source. The LTE-Lite is the cyan trace. Each image shows signals accumulated over a period of about 8-12 hours. As you can see, the relative timing of the two 1 Hz signals wanders by about +- 100 ns around a midpoint value, but at this midpoint the LTE-Lite is around 50 ns later that the Thunderbolt. (I call it a midpoint because it's judged by eye as halfway between the two recorded extremes. I don't have a record of the individual measurements, so I can't calculate mean or median). The Thunderbolt's antenna cable is perhaps 10 feet shorter than the LTE-Lite's, so that accounts for ~15 ns (Thunderbolt antennas compensation is set to zero). So, at my house, the LTE-Lite is about 50 ns late (or the TB is 50 ns early). That's one cycle of the LTE-Lite 20 MHz TCXO - coincidence? I also have an old Garmin GPS-25 board. This is a navigation GPS, without timing features, but it does have a 1 PPS output. I've included one capture of GPS-25 vs. Thunderbolt. The jitter is much worse; most (but not all) traces are within +- 400 ns of the Thunderbolt (note the different horizontal sweep). And there is also an overall bias: the Garmin receiver appears to be about 100 ns late on average compared to the TB. Unfortunately, I don't have any other way to measure which GPSDO has the more accurate PPS, and which one is responsible for most of the jitter. (A man with two GPSDOs never knows what time it is, precisely). I do have a big old 5 MHz OCXO pulled from a Transit receiver which is probably quite stable, but it is 0.2 Hz off nominal frequency and is not adjustable. Viewed on a scope alongside either GPSDO output, the 5 MHz phase shifts by one cycle every 5 seconds, too fast to make any comparison by eye of the stability of either GPSDO. - Dave On Mon, Dec 8, 2014 at 7:17 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: On the 10MHz LTE-Lite, how far out from true UTC would the PPS be expected to be? It seems to be about 200+ ns late on my unit, although it is much more stable than a typical GPS/PPS produces. Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] 1900kHz radiolcation testing on east coast US?
On 2014-12-07 16:28, Tim Shoppa wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Could it be an artifact of interference with NAA 1-1.8MW@24kHz which also uses ~3MW@60Hz for deicing on the inactive array, as it is now below freezing and fairly humid in coastal Maine http://en.wikipedia.org/wiki/VLF_Transmitter_Cutler -- Take care. Thanks, Brian Inglis ___ 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 LTE-Lite - PPS accuracy?
Hi On *most* GPSDO’s, the simple answer is “there is a cable delay adjustment to align it”. Without some sort of reliable representation of UTC (at the ns level) it’s tough to measure. If you happen to live at USNO or NIST, you can access that sort of timing. For the rest of us - not so easy. The NIST two way GPS “modem” setup is about the only practical method that I know of. The PPS out of any GPSDO will be much lower jitter than the pps from a normal GPS module. Bob == Bob, Thanks for your comments. The antenna location and cable lengths are very similar (either 0, 5m or 10m) so I was expecting somewhat less than 50 ns difference. 200+ ns is rather more than I expected for the LTE-Lite, so I did wonder whether anyone else had measured it. Although I've not checked it rigorously, most of the GPS/PPS units here of various brands are within under 100 ns of each other, hence my expectation. Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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 LTE-Lite - PPS accuracy?
Or use 1ns per foot of antenna cable. That will get you closer. Sent from mobile On Dec 8, 2014, at 8:16 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: Hi On *most* GPSDO’s, the simple answer is “there is a cable delay adjustment to align it”. Without some sort of reliable representation of UTC (at the ns level) it’s tough to measure. If you happen to live at USNO or NIST, you can access that sort of timing. For the rest of us - not so easy. The NIST two way GPS “modem” setup is about the only practical method that I know of. The PPS out of any GPSDO will be much lower jitter than the pps from a normal GPS module. Bob == Bob, Thanks for your comments. The antenna location and cable lengths are very similar (either 0, 5m or 10m) so I was expecting somewhat less than 50 ns difference. 200+ ns is rather more than I expected for the LTE-Lite, so I did wonder whether anyone else had measured it. Although I've not checked it rigorously, most of the GPS/PPS units here of various brands are within under 100 ns of each other, hence my expectation. Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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 LTE-Lite - PPS accuracy?
From: Bill Dailey Or use 1ns per foot of antenna cable. That will get you closer. == I was using 5ns per metre to allow for velocity factor. Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] 1900kHz radiolcation testing on east coast US?
On 2014-12-07 16:28, Tim Shoppa wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/__1910-intruder.wav http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/__1910-intruder-1.png http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/__1910-intruder-2.png http://www.trailing-edge.com/1910-intruder-2.png On Mon, Dec 8, 2014 at 9:15 AM, Brian Inglis brian.ing...@systematicsw.ab.ca mailto:brian.ing...@systematicsw.ab.ca wrote: Could it be an artifact of interference with NAA 1-1.8MW@24kHz which also uses ~3MW@60Hz for deicing on the inactive array, as it is now below freezing and fairly humid in coastal Maine http://en.wikipedia.org/wiki/__VLF_Transmitter_Cutler http://en.wikipedia.org/wiki/VLF_Transmitter_Cutler On 2014-12-08 07:30, Tim Shoppa wrote: 80*24 = 1920. 80th harmonic seems quite a stretch unless there is some malfunction (as you point out maybe an interaction with 60Hz heating... hmm... maybe they thought they could use PWM on the heating circuit.). For sure they have enough power and enough wire in the air to do the damage being observed. Do you know what the normal 24kHz waveform looks like? (FSK, MSK?) Some of the locals think it is iceland and that is pretty much the same beam heading as Cutler Maine. OK beam is a little optimistic,but we do have directional antennas for 160M and we do know which way is NE :-) Articles about NAA VLF say MSK@24kHz, that the deicing power available is quadruple the 3MW@60Hz to meet time goals, and it is operated remotely from somewhere around DC! -- Take care. Thanks, Brian Inglis ___ 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] 1900kHz radiolcation testing on east coast US?
80*24 = 1920. 80th harmonic seems quite a stretch unless there is some malfunction (as you point out maybe an interaction with 60Hz heating... hmm... maybe they thought they could use PWM on the heating circuit.). For sure they have enough power and enough wire in the air to do the damage being observed. Do you know what the normal 24kHz waveform looks like? (FSK, MSK?) Some of the locals think it is iceland and that is pretty much the same beam heading as Cutler Maine. OK beam is a little optimistic,but we do have directional antennas for 160M and we do know which way is NE :-) Tim N3QE On Mon, Dec 8, 2014 at 9:15 AM, Brian Inglis brian.ing...@systematicsw.ab.ca wrote: On 2014-12-07 16:28, Tim Shoppa wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Could it be an artifact of interference with NAA 1-1.8MW@24kHz which also uses ~3MW@60Hz for deicing on the inactive array, as it is now below freezing and fairly humid in coastal Maine http://en.wikipedia.org/wiki/VLF_Transmitter_Cutler -- Take care. Thanks, Brian Inglis ___ 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 LTE-Lite - PPS accuracy?
From: Dave Martindale What is the source of the 1 PPS you are comparing against? I compared my LTE-Lite to an old Thunderbolt (original model, single 24 V input with internal DC to DC converters, Piezo oscillator). At the time, the Thunderbolt had been running for a few months, while the LTE-Lite had been running for a week or so. Antennas were sitting on the window ledge of a west-facing window, so relatively poor sky coverage. I connected the PPS outputs from the two GPSDOs to two channels of a digital scope and left it running in accumulate mode. A couple of the resulting displays are attached below (I hope). Yellow trace is the Thunderbolt PPS, also the trigger source. The LTE-Lite is the cyan trace. Each image shows signals accumulated over a period of about 8-12 hours. As you can see, the relative timing of the two 1 Hz signals wanders by about +- 100 ns around a midpoint value, but at this midpoint the LTE-Lite is around 50 ns later that the Thunderbolt. (I call it a midpoint because it's judged by eye as halfway between the two recorded extremes. I don't have a record of the individual measurements, so I can't calculate mean or median). The Thunderbolt's antenna cable is perhaps 10 feet shorter than the LTE-Lite's, so that accounts for ~15 ns (Thunderbolt antennas compensation is set to zero). So, at my house, the LTE-Lite is about 50 ns late (or the TB is 50 ns early). That's one cycle of the LTE-Lite 20 MHz TCXO - coincidence? [] - Dave === Dave, My comparison is against a Rapco 1904M, which is another GPSDO. That does agree on a causal measurement with a number of simple GPS/PPS units I have. A u-blox LEA-6T shows about 80 ns later than the 1904M, and a u-blox NEO-6M between 50 ns early and 200 ns late, both after being on for just a few minutes, and with no special care in antenna placing. Do you think that your measurement (~35 ns offset) is consistent with the LTE-Lite specification: 1 PPS Timing Accuracy from GPS receiver 8ns to UTC RMS (1-Sigma) GPS Locked and the specification of the Thunderbolt? Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] 1900kHz radiolcation testing on east coast US?
Also hearing in central NH sounds like a new 'Woodpecker' Joy... Content by Scott Typos by Siri On Dec 8, 2014, at 2:24 AM, Chris Wilson ch...@chriswilson.tv wrote: Hello, on 08/12/2014 07:21 you wrote: I'm hearing the same signal in northern New Hampshire. Very strong 73, Frits W1FVB This is audible here in the UK and elicited many comments on 160 meters last night. Seen as oblique striations on SDR receiver displays and audible as a clicking sound. What the devil is it? -- Best Regards, Chris Wilson. ___ 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] 1900kHz radiolcation testing on east coast US?
On 12/8/14, 6:15 AM, Brian Inglis wrote: On 2014-12-07 16:28, Tim Shoppa wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Could it be an artifact of interference with NAA 1-1.8MW@24kHz which also uses ~3MW@60Hz for deicing on the inactive array, as it is now below freezing and fairly humid in coastal Maine http://en.wikipedia.org/wiki/VLF_Transmitter_Cutler A ham friend of mine noticed that a local grow house radiated a lot of power around 7.1 MHz with a very strong line structure at 183 kHz and harmonics. (Or thereabouts, he was telling me last week, I can't remember the exact). The 180 kHz is presumably from the DC/DC converters driving the lights. The spectrum bump around 7.1 MHz is speculated to be something from the physical configuration e.g. the length of the wires to the lights. Of course, these folks aren't particularly concerned about EMI/EMC issues (they rent a house in a residential neighborhood and do some redecoration). (they're not concerned, yet, until they realize that the RFI is like a big flashing light saying illegal grow operation here) ___ 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] Minicircuits specs
Gerhard Hoffmann wrote: Am 29.11.2014 um 20:01 schrieb Gerhard Hoffmann: Am 29.11.2014 um 19:08 schrieb Thomas S. Knutsen: 2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Ok, I volunteer to measure the S21 of a dc-force-fed T1-1 or T4-1 next weekend, when I'm back home. (DG8SAQ VNWA and / or WG TSA-2) Really, on osc, a voltmeter and a DC source are enough. Here it is: Mini circuits T1-1T, new very old stock, still in black case, not one of the new whitish ones that turn brown in the week after soldering. 0 / 25 / 50 / 100 mA on the secondary side from Agilent 6633B dc supply. It is nice that you can directly type in the voltages or currents. But you better do not take this thing for anything that is sensitive to noise. DG8SAQ VNWA, my best DC block from PSPL because it also has the lowest lower corner. It took some experimenting to find a choke that would not modify S21 and carry the current. Finally: a medium size red Amidon core two 220uH Siemens chokes with a looong air gap. https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The low frequency corner suffers already at 25 mA. The high frequency side is unimpressed by the current. Just what one expects from a transmission line transformer that gets ferrite as an anabolicum for the low frequencies. The transformer survived 1A for a short time and did not seem to suffer from that abuse s-parameter-wise. regards, Gerhard Many thanks for the graphs, Gerhard. I suspected that the low end would be the first to suffer, but didn't know how much. Those curves explain the reason for the 30ma limit; it's to keep the devices' specs definable. With a higher limit, the insertion loss specs would be terrible, and nobody would buy them. The text on the screen shots is a bit hard to read, but I think the curves told me what I wanted to know..As with most other devices, it's best to stay away from the Max figures on the datasheet. Thanks for taking the trouble to make the measurements and share the results. Dave 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] Linear voltage regulator hints...
Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan ___ 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] 1900kHz radiolcation testing on east coast US?
Recorded last night. Audio bandwidth is a few kHz, but as mentioned before the signal is about 20 kHz wide. https://www.dropbox.com/s/bnp8zcpgw86l6ww/1910.wav?dl=0 This morning (14:21 UTC) nothing is heard Frits W1FVB Whitefield, NH On 12/8/14, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Hello, Can someone please post a *.wav file of what it sounds like provided you have an SDR set-up? If you need someplace to post - please send the file to me offlist and I'll put it on either an ftp site or http. I am not so convinced what I saw wasn't noise or some stations from China transmitting - which I have seen in the 160m band lately. I got an AM band tonight also that was stomping all over ~ 3.87 MHz. Thanks! John AJ6BC On Mon, Dec 8, 2014 at 2:30 AM, Graham planoph...@aei.ca wrote: Radiolocation may be a bit misleading. Some first thought that this was CODAR but it is not, at least not what I am familiar with but it may be another variation of an ocean surface wave RADAR type of system but it is certainly not like one I have heard before. cheers, Graham ve3gtc On 2014-12-07 20:03, paul swed wrote: Not aware of any testing plus it makes no sense these days. LORAN long ago abandoned and was in that range and Loran C in the US dead. UrsaNav has been quite for quite a while. Regards Paul WB8TSL On Sun, Dec 7, 2014 at 7:09 PM, Bob Camp kb...@n1k.org wrote: Hi 120 Hz sub structure suggests a (much lower power) switching power supply run amok. I certainly would not design a system that would have virtually no immunity to power line noise . Bob On Dec 7, 2014, at 6:28 PM, Tim Shoppa tsho...@gmail.com wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/ 1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Tim N3QE ___ 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. -- vbradio.wordpress.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] Minicircuits specs
Please Gerhard, more details on your choke (medium size red Amidon core two 220 uH Siemens chokes). Maybe I can use it for 160 meter antennas. Your T1-1 measurements make sense according to my experience with these things. The -6 series (T1-6, etc) has larger cores and should withstand more DC. (I like to take apart MCL stuff to see what is inside; very enlightening). I always use the -6 series for 160 meter work. Thanks, 73 Rick Karlquist N6RK On 12/7/2014 10:14 PM, Gerhard Hoffmann wrote: Am 29.11.2014 um 20:01 schrieb Gerhard Hoffmann: DG8SAQ VNWA, my best DC block from PSPL because it also has the lowest lower corner. It took some experimenting to find a choke that would not modify S21 and carry the current. Finally: a medium size red Amidon core two 220uH Siemens chokes with a looong air gap. ___ 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] Minicircuits specs
Am 08.12.2014 um 18:57 schrieb Dave M: The text on the screen shots is a bit hard to read, but I think the curves told me what I wanted to know..As with most other devices, it's best to stay away from the Max figures on the datasheet. You can get the pictures by action - download and then watch them locally with the picture viewer of your choice. regards, Gerhard ___ 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] Z38XX Ulrichs program question How do you restart the graphs.
Boy I have dug through the program and can not seem to find a way to clear out the graphs. Tried exports and other things. Anyone know the secret please? Thanks Paul WB8TSL ___ 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] Z38XX Ulrichs program question How do you restart thegraphs.
Paul, I don't know for certain but with the limited playing around I have done with this program, I would start by renaming the data file and then let the program restart a new file from which I assume the graphs are plotted. I forget the file name off hand, might be something .dat or similar. It is a simple text file. cheers, Graham ve3gtc On 12/8/2014, paul swed paulsw...@gmail.com wrote: Boy I have dug through the program and can not seem to find a way to clear out the graphs. Tried exports and other things. Anyone know the secret please? Thanks Paul WB8TSL ___ 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] 1900kHz radiolcation testing on east coast US?
Hello Frits, Interesting. A little different than what I heard - but of course depends on the bandwidth somewhat. How many dB was this up from the noise floor? Or - what is the signal level of the received signal? What modulation did you try to decode or did you just set it wide-AM? I saw something like I mentioned around 1.915 MHz. It then dropped down to around 1.913 MHz - and then it went away. I did make a recording - but I didn't get the best part due to the signal moving down a bit - from 1.915 to 1.913 MHz. Thanks, John AJ6BC On Mon, Dec 8, 2014 at 6:22 AM, Frister fris...@gmx.net wrote: Recorded last night. Audio bandwidth is a few kHz, but as mentioned before the signal is about 20 kHz wide. https://www.dropbox.com/s/bnp8zcpgw86l6ww/1910.wav?dl=0 This morning (14:21 UTC) nothing is heard Frits W1FVB Whitefield, NH On 12/8/14, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Hello, Can someone please post a *.wav file of what it sounds like provided you have an SDR set-up? If you need someplace to post - please send the file to me offlist and I'll put it on either an ftp site or http. I am not so convinced what I saw wasn't noise or some stations from China transmitting - which I have seen in the 160m band lately. I got an AM band tonight also that was stomping all over ~ 3.87 MHz. Thanks! John AJ6BC On Mon, Dec 8, 2014 at 2:30 AM, Graham planoph...@aei.ca wrote: Radiolocation may be a bit misleading. Some first thought that this was CODAR but it is not, at least not what I am familiar with but it may be another variation of an ocean surface wave RADAR type of system but it is certainly not like one I have heard before. cheers, Graham ve3gtc On 2014-12-07 20:03, paul swed wrote: Not aware of any testing plus it makes no sense these days. LORAN long ago abandoned and was in that range and Loran C in the US dead. UrsaNav has been quite for quite a while. Regards Paul WB8TSL On Sun, Dec 7, 2014 at 7:09 PM, Bob Camp kb...@n1k.org wrote: Hi 120 Hz sub structure suggests a (much lower power) switching power supply run amok. I certainly would not design a system that would have virtually no immunity to power line noise . Bob On Dec 7, 2014, at 6:28 PM, Tim Shoppa tsho...@gmail.com wrote: Would any time-nuts know of radiolocation-type testing going on, on east coast of US, maybe around Maine? There is a very strong wideband signal on 1900-1920kHz, with a 120Hz substructure and a 4Hz rep-rate, likely megawatt power range. Sound sample (recorded with 2400Hz receiver bandwidth, although the whole signal is far far wider bandwidth) at http://www.trailing-edge.com/1910-intruder.wav Pics of the waveform at http://www.trailing-edge.com/ 1910-intruder-1.png and zoomed in at http://www.trailing-edge.com/1910-intruder-2.png Tim N3QE ___ 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. -- vbradio.wordpress.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] Linear voltage regulator hints...
Dan - Almost all the 3-terminal 7805-style regulators are going to have tempcos near -100 or -120PPM/DegC. Bare 5.6V zener has a tempco closer to 40PPM/DEGC. I don't know anything that combines the reference with the pass device in the same package and gets to a few PPM/degC. Obviously few-PPM references are readily available. Tim N3QE On Mon, Dec 8, 2014 at 1:18 PM, Dan Kemppainen d...@irtelemetrics.com wrote: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan ___ 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] Z38XX Ulrichs program question How do you restart the graphs.
Hi Paul, This puzzled me, too. Finally, I just deleted the txt file. Looking at, it, it looks like maybe it's a weekly file. For example: Z38XXData2014CW50.Txt, seems to mean week 50. At least that's my guess, since there's also a file Z38XXData2014CW49.Txt that was last modified Sun 07 Dec 2014 05:59:54 PM CST this morning. My tests are rather targeted, so I just delete whatever the file is and restart the program without paying close attention to the name when I start a new test. Bob From: paul swed paulsw...@gmail.com To: Time-nuts time-nuts@febo.com Sent: Monday, December 8, 2014 1:05 PM Subject: [time-nuts] Z38XX Ulrichs program question How do you restart the graphs. Boy I have dug through the program and can not seem to find a way to clear out the graphs. Tried exports and other things. Anyone know the secret please? Thanks Paul WB8TSL ___ 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 LTE-Lite
Time-Nuts Group, I thought some of you might be interested in my experience with the 10MHz LTE-Lite. The 10MHz LTE-Lite arrived about a week ago. I was not ready to make a permanent installation, I wanted it portable and I wanted to get started quickly. I am hobbyist interested mainly in the HF spectrum. So I decided to operate the LTE-Lite inside the Priority Mail box, which was pretty much intact. I cut a 5 X 8 piece of corrugated cardboard, mounted the unit on it with two doublestick pads, and put the cardboard with the unit into the Priority Mail box. I cut a hole in the top of the box so I could see the LEDs, and cut three small holes in the side, one for the USB cable, one for the antenna wire and one for the 10 MHz output. I attached the USB cable, antenna wire and 10 MHz output cable to the unit and ran them out of the box through the holes. I had an operating Lenovo X220 Windows 7 computer near to the box, so I plugged the USB cable into the computer (I did not try to get or use any software on the computer to decipher any messages from the LTE-Lite). I was in an upstairs North facing bedroom (in the Los Angeles area) so I put the antenna on a nearby windowsill. I hooked the 10MHz output to the channel 1 (Hi Z) input of my Tektronix 222A osciloscope, with the trigger on channel 1. When power was applied through the USB line, the LEDs seemed to light normally. Within a couple of hours the lock LED was on, but the oscilloscope was showing noise, not a meaningful output. I let the whole thing sit overnight, and the next day an apparent 10 MHz trace was on the screen. It was not a sine wave, and not a square wave, but something in between. I had a small Rb unit, an Efratom 10 MHz FRS-C built into a TM-500 plug-in. I set that up and let it warm up and lock. I connected the Rb output to channel 2 of the 222A and got that trace on the screen. It was a sine wave basically in lock step with the LTE-Lite trace. Over a few hours one could see slight relative movement, but very slight. What next? I had a couple of HP 5300 series frequency counters, one a 5300B display with Option 1 (Hi-Stability time base) and a 5308B lower unit, and the other a plain 5300B display with a 5303B Option 1 (Hi-Stability time base) lower unit. I give both time to warm up. I put a T in the LTE-Lite output line and another T in the Rb output line, and connected coax from the Ts to the HiZ input of each frequency counter. After they settled down, the counter connected to the LTE-Lite read 1008 and the counter connected to the Rb read 1002. So, after a while, I reversed the leads to the counters, and the counter connected to the LTE-Lite read 1002 and the one conntected to the Rb read 1008. Those readings have been consistent for several days. That indicated to me that the LTE-Lite and the Rb were both outputing essentially the same frequency, but the counters were a bit off (I had never calibrated these counters, since I wasn't sure of the accuracy of the Rb unit). But, I felt like the proverbial man with two watches. So, I brought out Big Gonzo, a HP 5335A counter with Option 010 (Hi-Stability time base) I purchased on eBay about six months ago but had never fired up. It came up OK and I hooked it to the LTE-Lite output. It initially read 1028, but I gave it a couple of hours to warm up the oscillator oven and stabilize. By then, the reading had settled to 10 000 000. Now I switched cables and hooked the Rb to the 5335A, and it read 10 000 000. I hooked the LTE-Lite to channel A of the 5335A and the Rb to channel B of the 5335A, and set the counter to ratio. When it settled, the counter read 1.000 000 indicating that the two outputs were the same frequency, at least to six decimals. Apparently the 5335A is right on. I conclude that both the LTE-Lite and the Rb are outputting a 1000 MHz signal. I'm not sure of the accuracy beyond that. They are probably both accurate enough for my purposes for calibrating other test equipment, receivers and transmitters operating in the HF spectrum. I would be interested in any comments or suggestions from other list members. Byron WA6ATN ___ 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] Minicircuits specs
Am 08.12.2014 um 19:26 schrieb Richard (Rick) Karlquist: Please Gerhard, more details on your choke (medium size red Amidon core two 220 uH Siemens chokes). Maybe I can use it for 160 meter antennas. Siemens Chokes: yellow, 5.5mm dia, 27 mm long, a single ferrite rod with a lot of turns. They still have the SH logo, must be 20 years old 221.9 uH Q=17 at 100 KHz, measured on the 4274A impedance meter. Amidon: Red, the usual 80m material, 20.5mm o.d. 17 turns 0.5mm CuAg 1.962 uH Q=24 at 100 KHz pic of the inductors at https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The board in the background is my 5/10 MHz buffer, NIST FET doubler with 2*BF862, distribution amplifier 4 * 12 dBm based on AD8009 / LMH6702, in statu nascendi. Yesterday I drew etched the board, at the moment I'm just populating it. All 0603, sot23-5 and the like. Size is just 32 * 68 mm without the protruding SMAs. The next picture is how the Lucent RFTG-u REF1 looks with the board mounted inside. And many thanks to the people who wrote up how to power up the Lucent. It has helped me a lot. regards, Gerhard, dk4xp ___ 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 LTE-Lite
On Mon, Dec 8, 2014 at 11:07 AM, Byron Hayes Jr bha...@earthlink.net wrote: So, I brought out Big Gonzo, a HP 5335A counter with Option 010 (Hi-Stability time base) I purchased on eBay about six months ago but had never fired up. It came up OK and I hooked it to the LTE-Lite output. It initially read 1028, but I gave it a couple of hours to warm up the oscillator oven and stabilize. By then, the reading had settled to 10 000 000. Now I switched cables and hooked the Rb to the 5335A, and it read 10 000 000. I hooked the LTE-Lite to channel A of the 5335A and the Rb to channel B of the 5335A, and set the counter to ratio. When it settled, the counter read 1.000 000 indicating that the two outputs were the same frequency, at least to six decimals. Apparently the 5335A is right on. You can get another couple of digits for frequency out of the 5335A by setting the gate longer... I use about 2 o'clock on the Gate Adj. pot. My 5335A is now reading 9 999 999.96 for both LTE Lite and Trimble Thunderbolt. It must be coming on 4 years since Joe/KN5U adjusted the OCXO in the 5335A, so its drift seems well within spec. Orin. ___ 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] Z38XX Ulrichs program question How do you restart the graphs.
Thanks everyone. I thought I was missing the magical super secret ctl ... sequence. Regards Paul. On Mon, Dec 8, 2014 at 2:37 PM, Bob Stewart b...@evoria.net wrote: Hi Paul, This puzzled me, too. Finally, I just deleted the txt file. Looking at, it, it looks like maybe it's a weekly file. For example: Z38XXData2014CW50.Txt, seems to mean week 50. At least that's my guess, since there's also a file Z38XXData2014CW49.Txt that was last modified Sun 07 Dec 2014 05:59:54 PM CST this morning. My tests are rather targeted, so I just delete whatever the file is and restart the program without paying close attention to the name when I start a new test. Bob From: paul swed paulsw...@gmail.com To: Time-nuts time-nuts@febo.com Sent: Monday, December 8, 2014 1:05 PM Subject: [time-nuts] Z38XX Ulrichs program question How do you restart the graphs. Boy I have dug through the program and can not seem to find a way to clear out the graphs. Tried exports and other things. Anyone know the secret please? Thanks Paul WB8TSL ___ 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] 10MHz LTE-Lite - PPS accuracy?
I work with Said at Jackson Labs. I've been reading the time-nuts discussion for a few years, but rarely chime in. I saw this discussion and wanted to make a couple points. * The LTE Lite time accuracy specification corresponds with the Skytraq GPS receiver's specs page which I have attached. The specification is for the output directly from the GPS receiver available on the LTE Lite Eval Board's JP1 connector pin 12. This specification assumes optimal antenna placement and thermal conditions, and position hold mode. It is also an RMS (1-sigma) measurement not a peak-to-peak measurement. * The GPSDO-generated 1PPS on the LTE Lite Eval Board's J1 connector has a phase offset to the GPS raw 1PPS that is shown in the PJLTS message (2nd field). The GPSDO functions to drive this phase offset to zero. But at a given time--especially shortly after power up--the offset may 100 ns or more. Keith Keith On Mon, Dec 8, 2014 at 7:12 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: From: Dave Martindale What is the source of the 1 PPS you are comparing against? I compared my LTE-Lite to an old Thunderbolt (original model, single 24 V input with internal DC to DC converters, Piezo oscillator). At the time, the Thunderbolt had been running for a few months, while the LTE-Lite had been running for a week or so. Antennas were sitting on the window ledge of a west-facing window, so relatively poor sky coverage. I connected the PPS outputs from the two GPSDOs to two channels of a digital scope and left it running in accumulate mode. A couple of the resulting displays are attached below (I hope). Yellow trace is the Thunderbolt PPS, also the trigger source. The LTE-Lite is the cyan trace. Each image shows signals accumulated over a period of about 8-12 hours. As you can see, the relative timing of the two 1 Hz signals wanders by about +- 100 ns around a midpoint value, but at this midpoint the LTE-Lite is around 50 ns later that the Thunderbolt. (I call it a midpoint because it's judged by eye as halfway between the two recorded extremes. I don't have a record of the individual measurements, so I can't calculate mean or median). The Thunderbolt's antenna cable is perhaps 10 feet shorter than the LTE-Lite's, so that accounts for ~15 ns (Thunderbolt antennas compensation is set to zero). So, at my house, the LTE-Lite is about 50 ns late (or the TB is 50 ns early). That's one cycle of the LTE-Lite 20 MHz TCXO - coincidence? [] - Dave === Dave, My comparison is against a Rapco 1904M, which is another GPSDO. That does agree on a causal measurement with a number of simple GPS/PPS units I have. A u-blox LEA-6T shows about 80 ns later than the 1904M, and a u-blox NEO-6M between 50 ns early and 200 ns late, both after being on for just a few minutes, and with no special care in antenna placing. Do you think that your measurement (~35 ns offset) is consistent with the LTE-Lite specification: 1 PPS Timing Accuracy from GPS receiver 8ns to UTC RMS (1-Sigma) GPS Locked and the specification of the Thunderbolt? Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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. Venus838LPx-T-Specs.pdf Description: Adobe PDF document ___ 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 LTE-Lite - PPS accuracy?
Hi If you read the NIST papers where they have looked at the PPS accuracy compared to UTC, the results are not all that good. The assumption that any one GSDO is “correct” compared to UTC is *not* a good one. The consistency of a GPSDO is quite good. That’s a very different thing than it’s accuracy (delta to UTC). In the case that absolute error relative to UTC is a requirement, you need a local UTC reference. The antenna delay setting is then used to “align” all of your GPSDO’s against your reference. On many GPSDO’s the antenna delay adjustment is a 100 ns resolution sort of thing. Again, it’s important to understand that these boxes were all made for cell service. That’s not an application where exact traceability to UTC is needed. Simply having all the sites run the same (consistent) GPSDO is perfectly adequate. If you have two brands of GPSDO, figure out the offset between them, still no need for “real” UTC. The “UTC” specs you see are one sigma bounds on the wander. Offset / centering of that peak are an unknown that is buried deep in the fine print. Bob On Dec 8, 2014, at 10:12 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: From: Dave Martindale What is the source of the 1 PPS you are comparing against? I compared my LTE-Lite to an old Thunderbolt (original model, single 24 V input with internal DC to DC converters, Piezo oscillator). At the time, the Thunderbolt had been running for a few months, while the LTE-Lite had been running for a week or so. Antennas were sitting on the window ledge of a west-facing window, so relatively poor sky coverage. I connected the PPS outputs from the two GPSDOs to two channels of a digital scope and left it running in accumulate mode. A couple of the resulting displays are attached below (I hope). Yellow trace is the Thunderbolt PPS, also the trigger source. The LTE-Lite is the cyan trace. Each image shows signals accumulated over a period of about 8-12 hours. As you can see, the relative timing of the two 1 Hz signals wanders by about +- 100 ns around a midpoint value, but at this midpoint the LTE-Lite is around 50 ns later that the Thunderbolt. (I call it a midpoint because it's judged by eye as halfway between the two recorded extremes. I don't have a record of the individual measurements, so I can't calculate mean or median). The Thunderbolt's antenna cable is perhaps 10 feet shorter than the LTE-Lite's, so that accounts for ~15 ns (Thunderbolt antennas compensation is set to zero). So, at my house, the LTE-Lite is about 50 ns late (or the TB is 50 ns early). That's one cycle of the LTE-Lite 20 MHz TCXO - coincidence? [] - Dave === Dave, My comparison is against a Rapco 1904M, which is another GPSDO. That does agree on a causal measurement with a number of simple GPS/PPS units I have. A u-blox LEA-6T shows about 80 ns later than the 1904M, and a u-blox NEO-6M between 50 ns early and 200 ns late, both after being on for just a few minutes, and with no special care in antenna placing. Do you think that your measurement (~35 ns offset) is consistent with the LTE-Lite specification: 1 PPS Timing Accuracy from GPS receiver 8ns to UTC RMS (1-Sigma) GPS Locked and the specification of the Thunderbolt? Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] Linear voltage regulator hints...
Hi As with anything else it’s a matter of “what’s in your wallet”. The parts you are after are called voltage references rather than voltage regulators. You can get them well down into the low ppm’s / C or lower. The cutoff is more a function of “do you want to spend $100 or not” rather than a specific level you simply can’t get to. Bob On Dec 8, 2014, at 1:18 PM, Dan Kemppainen d...@irtelemetrics.com wrote: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan ___ 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 LTE-Lite
HI At a 1 second gate, your 5335 is good to about 1 ppb. (1x10^-9). A TCXO based GPSDO should be good to 10X that level. An OCXO based unit should be good to 100X that level. If you extend the counter’s gate time, the 5335 will overflow fairly quickly. Up to the point it does, it’s accuracy will improve directly with the gate time. Once it overflows, you can correct the result, but it is messy. Bob On Dec 8, 2014, at 2:07 PM, Byron Hayes Jr bha...@earthlink.net wrote: Time-Nuts Group, I thought some of you might be interested in my experience with the 10MHz LTE-Lite. The 10MHz LTE-Lite arrived about a week ago. I was not ready to make a permanent installation, I wanted it portable and I wanted to get started quickly. I am hobbyist interested mainly in the HF spectrum. So I decided to operate the LTE-Lite inside the Priority Mail box, which was pretty much intact. I cut a 5 X 8 piece of corrugated cardboard, mounted the unit on it with two doublestick pads, and put the cardboard with the unit into the Priority Mail box. I cut a hole in the top of the box so I could see the LEDs, and cut three small holes in the side, one for the USB cable, one for the antenna wire and one for the 10 MHz output. I attached the USB cable, antenna wire and 10 MHz output cable to the unit and ran them out of the box through the holes. I had an operating Lenovo X220 Windows 7 computer near to the box, so I plugged the USB cable into the computer (I did not try to get or use any software on the computer to decipher any messages from the LTE-Lite). I was in a n upstairs North facing bedroom (in the Los Angeles area) so I put the antenna on a nearby windowsill. I hooked the 10MHz output to the channel 1 (Hi Z) input of my Tektronix 222A osciloscope, with the trigger on channel 1. When power was applied through the USB line, the LEDs seemed to light normally. Within a couple of hours the lock LED was on, but the oscilloscope was showing noise, not a meaningful output. I let the whole thing sit overnight, and the next day an apparent 10 MHz trace was on the screen. It was not a sine wave, and not a square wave, but something in between. I had a small Rb unit, an Efratom 10 MHz FRS-C built into a TM-500 plug-in. I set that up and let it warm up and lock. I connected the Rb output to channel 2 of the 222A and got that trace on the screen. It was a sine wave basically in lock step with the LTE-Lite trace. Over a few hours one could see slight relative movement, but very slight. What next? I had a couple of HP 5300 series frequency counters, one a 5300B display with Option 1 (Hi-Stability time base) and a 5308B lower unit, and the other a plain 5300B display with a 5303B Option 1 (Hi-Stability time base) lower unit. I give both time to warm up. I put a T in the LTE-Lite output line and another T in the Rb output line, and connected coax from the Ts to the HiZ input of each frequency counter. After they settled down, the counter connected to the LTE-Lite read 1008 and the counter connected to the Rb read 1002. So, after a while, I reversed the leads to the counters, and the counter connected to the LTE-Lite read 1002 and the one conntected to the Rb read 1008. Those readings have been consistent for several days. That indicated to me that the LTE-Lite and the Rb were both outputing essentially the same frequency, but the counters were a bit off (I had never calibrated these counters, since I wasn't sure of the accuracy of the Rb unit). But, I felt like the proverbial man with two watches. So, I brought out Big Gonzo, a HP 5335A counter with Option 010 (Hi-Stability time base) I purchased on eBay about six months ago but had never fired up. It came up OK and I hooked it to the LTE-Lite output. It initially read 1028, but I gave it a couple of hours to warm up the oscillator oven and stabilize. By then, the reading had settled to 10 000 000. Now I switched cables and hooked the Rb to the 5335A, and it read 10 000 000. I hooked the LTE-Lite to channel A of the 5335A and the Rb to channel B of the 5335A, and set the counter to ratio. When it settled, the counter read 1.000 000 indicating that the two outputs were the same frequency, at least to six decimals. Apparently the 5335A is right on. I conclude that both the LTE-Lite and the Rb are outputting a 1000 MHz signal. I'm not sure of the accuracy beyond that. They are probably both accurate enough for my purposes for calibrating other test equipment, receivers and transmitters operating in the HF spectrum. I would be interested in any comments or suggestions from other list members. Byron WA6ATN ___ 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] 10MHz LTE-Lite
Enabling MEAN with 100 pts under Statistics should give an additional digit but will take a few minutes for a reading with longer gate times. Keith Keith On Mon, Dec 8, 2014 at 3:07 PM, Bob Camp kb...@n1k.org wrote: HI At a 1 second gate, your 5335 is good to about 1 ppb. (1x10^-9). A TCXO based GPSDO should be good to 10X that level. An OCXO based unit should be good to 100X that level. If you extend the counter’s gate time, the 5335 will overflow fairly quickly. Up to the point it does, it’s accuracy will improve directly with the gate time. Once it overflows, you can correct the result, but it is messy. Bob On Dec 8, 2014, at 2:07 PM, Byron Hayes Jr bha...@earthlink.net wrote: Time-Nuts Group, I thought some of you might be interested in my experience with the 10MHz LTE-Lite. The 10MHz LTE-Lite arrived about a week ago. I was not ready to make a permanent installation, I wanted it portable and I wanted to get started quickly. I am hobbyist interested mainly in the HF spectrum. So I decided to operate the LTE-Lite inside the Priority Mail box, which was pretty much intact. I cut a 5 X 8 piece of corrugated cardboard, mounted the unit on it with two doublestick pads, and put the cardboard with the unit into the Priority Mail box. I cut a hole in the top of the box so I could see the LEDs, and cut three small holes in the side, one for the USB cable, one for the antenna wire and one for the 10 MHz output. I attached the USB cable, antenna wire and 10 MHz output cable to the unit and ran them out of the box through the holes. I had an operating Lenovo X220 Windows 7 computer near to the box, so I plugged the USB cable into the computer (I did not try to get or use any software on the computer to decipher any messages from the LTE-Lite). I was in a n upstairs North facing bedroom (in the Los Angeles area) so I put the antenna on a nearby windowsill. I hooked the 10MHz output to the channel 1 (Hi Z) input of my Tektronix 222A osciloscope, with the trigger on channel 1. When power was applied through the USB line, the LEDs seemed to light normally. Within a couple of hours the lock LED was on, but the oscilloscope was showing noise, not a meaningful output. I let the whole thing sit overnight, and the next day an apparent 10 MHz trace was on the screen. It was not a sine wave, and not a square wave, but something in between. I had a small Rb unit, an Efratom 10 MHz FRS-C built into a TM-500 plug-in. I set that up and let it warm up and lock. I connected the Rb output to channel 2 of the 222A and got that trace on the screen. It was a sine wave basically in lock step with the LTE-Lite trace. Over a few hours one could see slight relative movement, but very slight. What next? I had a couple of HP 5300 series frequency counters, one a 5300B display with Option 1 (Hi-Stability time base) and a 5308B lower unit, and the other a plain 5300B display with a 5303B Option 1 (Hi-Stability time base) lower unit. I give both time to warm up. I put a T in the LTE-Lite output line and another T in the Rb output line, and connected coax from the Ts to the HiZ input of each frequency counter. After they settled down, the counter connected to the LTE-Lite read 1008 and the counter connected to the Rb read 1002. So, after a while, I reversed the leads to the counters, and the counter connected to the LTE-Lite read 1002 and the one conntected to the Rb read 1008. Those readings have been consistent for several days. That indicated to me that the LTE-Lite and the Rb were both outputing essentially the same frequency, but the counters were a bit off (I had never calibrated these counters, since I wasn't sure of the accuracy of the Rb unit). But, I felt like the proverbial man with two watches. So, I brought out Big Gonzo, a HP 5335A counter with Option 010 (Hi-Stability time base) I purchased on eBay about six months ago but had never fired up. It came up OK and I hooked it to the LTE-Lite output. It initially read 1028, but I gave it a couple of hours to warm up the oscillator oven and stabilize. By then, the reading had settled to 10 000 000. Now I switched cables and hooked the Rb to the 5335A, and it read 10 000 000. I hooked the LTE-Lite to channel A of the 5335A and the Rb to channel B of the 5335A, and set the counter to ratio. When it settled, the counter read 1.000 000 indicating that the two outputs were the same frequency, at least to six decimals. Apparently the 5335A is right on. I conclude that both the LTE-Lite and the Rb are outputting a 1000 MHz signal. I'm not sure of the accuracy beyond that. They are probably both accurate enough for my purposes for calibrating other test equipment, receivers and transmitters operating in the HF spectrum. I would be interested in any comments or suggestions from other list members. Byron WA6ATN
Re: [time-nuts] 10MHz LTE-Lite
Said asked me to forward this: Hello Orin, very nice job on the buffer design! This confirms that minor changes in power consumption due to load changes on the board affect oscillator stability. The 10MHz oscillator itself is rated at up to +/-5ppb for load-induced changes, so that is very significant considering that we are trying to stabilize it to 0.1ppb and better. It also confirms that the cables on the 10MHz DIP-14 version should be kept as short as possible. The 20MHz units have a buffer behind the oscillator of course, so should have less load-change sensitivity, but it will be there - no doubt. Bye, Said Keith On Sat, Dec 6, 2014 at 10:32 PM, Orin Eman orin.e...@gmail.com wrote: Hi Said, It's a little while since you sent this, but I just finished some testing with the LTE Lite. I already had a Trimble Thunderbolt and also have an HP 5335A with OCXO. The 5335A has shown the Trimble O/P 10 MHz +/- 0.03 Hz for the last few years (displayed frequency on the 5335A has drifted down by about 0.04 Hz). So, I set up the LTE Lite (10MHz TCXO version) with its antenna about 6' from that used by the Trimble. After letting it settle down, it looked good. I was using the high impedance input of the 5335A (aside: if set for DC coupling, the 5335A would read 20MHz from the ringing. I only have about 18 of RG-188 after the pigtail supplied with the LTE Lite). Today, I made up a buffer using a 74AC04 and LT1763-3.3 LDO regulator supplied with 5V from a bench supply. Two inverters each into 100 ohms then 0.1uF DC block as suggested. I connected this to the LTE Lite instead of directly to the 5335A with the 5335A set to 50 ohms and the 5335A read 0.5Hz low! It settled down to the original reading after a while. I looked at the signal from the buffer using a 50 ohm pass-through terminator and the signal looked nice and square. A few hours later I went back and it still looked good. I decided to look at the input to the buffer on a TDS-210 'scope with a 10X probe. There is now perhaps 6 of coax to the buffer which has 1 Mohm in parallel. The signal is about 5V pk-pk, but the ringing dies down quickly. BUT, the 5335A was displaying a few hundredths of a Hz higher than 10MHz, whereas it was a few hundredths below before! When I removed the probe, it went a few hundredths of a Hz below where it was originally and gradually recovered. So, in addition to temperature, the LTE-Lite eval board with 10MHz TCXO appears to be sensitive to load as well as temperature, such that just a 10X oscilloscope probe will affect the output. Normally, you probably wouldn't notice this, but I switched the loads while it was running. Certainly, once put in an enclosure, the 74AC04 buffer would be permanently connected and I'd assume any effect noticed above would be during the warmup of the LTE-Lite and wouldn't really be noticed. I'm sure I forgot some detail or other in the above description. I couldn't find a DIP 74AC04 so I made a PCB for an SMT 784AC04 using MG Chemicals 1/32 positive-resist PCB and Eagle for the design; 1206 100 ohm series resistors and 1206 0.1uF ceramic DC blocking capacitors. I laid it out for SMA sockets that you could wire RG-316 or similar directly instead. I used a 6 MMCX to RG-316 pigtail from the LTE-Lite to my buffer. I mounted one SMA socket on the outputs which is what I used to connect to the HP 5335A. The LT1763 has a 1uF 35V tantalum on the input and 10 uF 30V tantalum on the output (they are what I had in the parts bin, or I'd have used *smaller* ceramic parts). I tweaked the design for hand soldering with no solder mask (i.e. 20 mil clearances and top layer restrictions around most components to keep the ground fill away). Orin. On Sat, Nov 22, 2014 at 9:44 AM, Said Jackson via time-nuts time-nuts@febo.com wrote: Hi Paul, Jim, David, Let me address all your emails: Glad you got your boards. $50 in overseas additional charges from your post office sucks! Some hints for experimenting from what I have learned: You definitely want to build a 50 Ohms buffer for the 10MHz boards and the synthesized outputs on all boards; on the 20MHz boards on the Tcxo output it's optional. The biggest problem is building a suitable 3.3V or 5V power supply. I built a buffer using two NC7SZ04 chips receiving the input in parallel with a 1M terminating resistor to ground. Then using a 100 Ohms series resistor on both outputs to get ~55 Ohms equivalent impedance, and combining the two R's to drive the 50 Ohms inputs through a 100nF cap for DC blocking. You can use a 74AC04 just as well. I tried a standard high quality 3-pin regulator and got very bad AM noise modulation due to the large noise on the rail. Then I used a very low noise LDO from LT and that solved the problem and the output is now very clean and drives 50 Ohms inputs with ease. you can grab the very low noise 3.0V rail output
Re: [time-nuts] Linear voltage regulator hints...
Dan Kemppainen wrote: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan Yes, in order to get low PPM stability, you are going to roll your own. No 3-terminal regulator or reference that I know of can run an OXCO (heater and oscillator). What are your voltage and current requirements? Dave 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.
Re: [time-nuts] 10MHz LTE-Lite
Hi On the 5335, the display changes a bit as you fiddle with the math. The actual resolution does not change. When you get an extra digit, it really does not step off in one count steps. Anything you do that gets you to a 10X longer gate time does add a “real” digit. Taking 10 back to back readings increases the display by about 1/3 of a digit (back to the square root N issue). Bob On Dec 8, 2014, at 6:09 PM, Keith Loiselle keith.loise...@gmail.com wrote: Enabling MEAN with 100 pts under Statistics should give an additional digit but will take a few minutes for a reading with longer gate times. Keith Keith On Mon, Dec 8, 2014 at 3:07 PM, Bob Camp kb...@n1k.org wrote: HI At a 1 second gate, your 5335 is good to about 1 ppb. (1x10^-9). A TCXO based GPSDO should be good to 10X that level. An OCXO based unit should be good to 100X that level. If you extend the counter’s gate time, the 5335 will overflow fairly quickly. Up to the point it does, it’s accuracy will improve directly with the gate time. Once it overflows, you can correct the result, but it is messy. Bob On Dec 8, 2014, at 2:07 PM, Byron Hayes Jr bha...@earthlink.net wrote: Time-Nuts Group, I thought some of you might be interested in my experience with the 10MHz LTE-Lite. The 10MHz LTE-Lite arrived about a week ago. I was not ready to make a permanent installation, I wanted it portable and I wanted to get started quickly. I am hobbyist interested mainly in the HF spectrum. So I decided to operate the LTE-Lite inside the Priority Mail box, which was pretty much intact. I cut a 5 X 8 piece of corrugated cardboard, mounted the unit on it with two doublestick pads, and put the cardboard with the unit into the Priority Mail box. I cut a hole in the top of the box so I could see the LEDs, and cut three small holes in the side, one for the USB cable, one for the antenna wire and one for the 10 MHz output. I attached the USB cable, antenna wire and 10 MHz output cable to the unit and ran them out of the box through the holes. I had an operating Lenovo X220 Windows 7 computer near to the box, so I plugged the USB cable into the computer (I did not try to get or use any software on the computer to decipher any messages from the LTE-Lite). I was in a n upstairs North facing bedroom (in the Los Angeles area) so I put the antenna on a nearby windowsill. I hooked the 10MHz output to the channel 1 (Hi Z) input of my Tektronix 222A osciloscope, with the trigger on channel 1. When power was applied through the USB line, the LEDs seemed to light normally. Within a couple of hours the lock LED was on, but the oscilloscope was showing noise, not a meaningful output. I let the whole thing sit overnight, and the next day an apparent 10 MHz trace was on the screen. It was not a sine wave, and not a square wave, but something in between. I had a small Rb unit, an Efratom 10 MHz FRS-C built into a TM-500 plug-in. I set that up and let it warm up and lock. I connected the Rb output to channel 2 of the 222A and got that trace on the screen. It was a sine wave basically in lock step with the LTE-Lite trace. Over a few hours one could see slight relative movement, but very slight. What next? I had a couple of HP 5300 series frequency counters, one a 5300B display with Option 1 (Hi-Stability time base) and a 5308B lower unit, and the other a plain 5300B display with a 5303B Option 1 (Hi-Stability time base) lower unit. I give both time to warm up. I put a T in the LTE-Lite output line and another T in the Rb output line, and connected coax from the Ts to the HiZ input of each frequency counter. After they settled down, the counter connected to the LTE-Lite read 1008 and the counter connected to the Rb read 1002. So, after a while, I reversed the leads to the counters, and the counter connected to the LTE-Lite read 1002 and the one conntected to the Rb read 1008. Those readings have been consistent for several days. That indicated to me that the LTE-Lite and the Rb were both outputing essentially the same frequency, but the counters were a bit off (I had never calibrated these counters, since I wasn't sure of the accuracy of the Rb unit). But, I felt like the proverbial man with two watches. So, I brought out Big Gonzo, a HP 5335A counter with Option 010 (Hi-Stability time base) I purchased on eBay about six months ago but had never fired up. It came up OK and I hooked it to the LTE-Lite output. It initially read 1028, but I gave it a couple of hours to warm up the oscillator oven and stabilize. By then, the reading had settled to 10 000 000. Now I switched cables and hooked the Rb to the 5335A, and it read 10 000 000. I hooked the LTE-Lite to channel A of the 5335A and the Rb to channel B of the 5335A, and set the counter to ratio. When it settled, the counter read 1.000 000 indicating that the two outputs were the
[time-nuts] Motorola Lightning Protection Article
List, I have reproduced a Motorola Lightning Protection article from the PPRA newsletter from the early 80's. If anyone wants a copy please send me an ORIGINAL email off list and I'll send you a PDF. I will also post a copy to Didier's web site in a few days. 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.
Re: [time-nuts] Linear voltage regulator hints...
Hi Hopefully the issue (and question) is about stability of the EFC voltage. Any decent OCXO should have a voltage stability that’s well below it’s temperature stability when run off of a fairly standard regulator. As an example, An OCXO that does 5x10^-9 over 0 to 70 C probably has a voltage stability below 5x10^-10 for a 1% change. One percent is more than what a modern regulator should be moving when running an OCXO. Bob On Dec 8, 2014, at 7:33 PM, Dave M dgmin...@mediacombb.net wrote: Dan Kemppainen wrote: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan Yes, in order to get low PPM stability, you are going to roll your own. No 3-terminal regulator or reference that I know of can run an OXCO (heater and oscillator). What are your voltage and current requirements? Dave 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] Linear voltage regulator hints...
Am 08.12.2014 um 19:18 schrieb Dan Kemppainen: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan Hi Dan, I like to use the universal LM723C or µA723C, manuf. eg. Ti or NS Short description: it contains a temperature compensated reference source Vref Zener, ext. filter C is connectable to further reduce noise abt. 150 ppm/°K offset drift, but possible to work with ext. ref. as eg. LM129, 1n82x, LM399 etc. still available in N (DIL14), J, U, FK packages The LM723 can produce up to 150mA of output current without additional transistors hp did use it quite often in their equipment. Lot of example circuits and hints can be found in the internet to avoid unwanted oscillations use ceramic Cs as close as possible connected to the circuit. Good luck, Arnold, DK2WT ___ 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] Linear voltage regulator hints...
We solved that problem by attaching the regulators to the FRK back plate which is with fan control is kept within 0.01C. We did not do it for that purpose but found that we needed some more heat in order to keep the fan in an optimum fan speed. Rb, OCXO and Fan power transistor are on the back plate. Works for us. Bert Kehren In a message dated 12/8/2014 7:33:46 P.M. Eastern Standard Time, dgmin...@mediacombb.net writes: Dan Kemppainen wrote: Hi, In playing with some oscillators and a GPSDO here, I think I'm seeing a voltage sensitivity issue. So, I started looking at the output voltage of various regulators vs. temp. Using standard LM/UA type linear regulators and some LDO's, they all appear to be pretty sensitive to temperature. (millivolt / few degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to ignore temp sensitivity. Almost like they are so bad they don't want to publish it... Does anyone have hints on TO-220 or D-Pak type regulators that have really good temp coefficients and good line regulation? A few PPM/Deg C might be nice, if possible. Or am I into a 'roll you own' type design... Dan Yes, in order to get low PPM stability, you are going to roll your own. No 3-terminal regulator or reference that I know of can run an OXCO (heater and oscillator). What are your voltage and current requirements? Dave 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.
[time-nuts] PRS-45A is alive!
Well, it's alive, and I even have 10MHz coming from it. It took about 16 minutes to go to lock. Is that good, or doesn't matter? Now I've got to put together a serial cable and see if I can talk to it and find out how it thinks it's doing. But, this is good! www.evoria.net/AE6RV/PRS-45A/2014-12-08%2020.51.33.jpg Hope you enjoy the wall decorations. =) Bob - AE6RV ___ 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] Linear voltage regulator hints...
On 12/8/2014 4:53 PM, Bert Kehren via time-nuts wrote: We solved that problem by attaching the regulators to the FRK back plate which is with fan control is kept within 0.01C. We did not do it for that purpose but found that we needed some more heat in order to keep the fan in an optimum fan speed. Rb, OCXO and Fan power transistor are on the back plate. Works for us. Bert Kehren When I designed the E1938A, I chose a reasonable looking voltage reference IC and put it inside the oven. I figured that was the end of it as far as tempco was concerned. It was, but it turned out that the *noise* of the reference was unacceptable and of course the oven does nothing to fix that. I had to switch to a lower noise reference. Rick Karlquist N6RK ___ 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] Linear voltage regulator hints...
Hi Rich: Did you use the 723 or . . . .? As far as I know the 723 is supposed to have low noise. Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Richard (Rick) Karlquist wrote: On 12/8/2014 4:53 PM, Bert Kehren via time-nuts wrote: We solved that problem by attaching the regulators to the FRK back plate which is with fan control is kept within 0.01C. We did not do it for that purpose but found that we needed some more heat in order to keep the fan in an optimum fan speed. Rb, OCXO and Fan power transistor are on the back plate. Works for us. Bert Kehren When I designed the E1938A, I chose a reasonable looking voltage reference IC and put it inside the oven. I figured that was the end of it as far as tempco was concerned. It was, but it turned out that the *noise* of the reference was unacceptable and of course the oven does nothing to fix that. I had to switch to a lower noise reference. Rick Karlquist N6RK ___ 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] 1900kHz radiolcation testing on east coast US?
John, On 12/8/14, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Hello Frits, Interesting. A little different than what I heard - but of course depends on the bandwidth somewhat. I think my bandwidth was set at about 8 Khz How many dB was this up from the noise floor? Or - what is the signal level of the received signal? What modulation did you try to decode or did you just set it wide-AM? I've build a down converter in my old IC-735 and have about 22 Khz of spectrum to look at at once. Using Xlinrad as the SDR. Had the audio passband in Double Side Band mode.. 4 kHz below and 4 kHz above the center frequency. Signal strength in Linrad wasn't calibrated , but on the icom analog meter S9+30 dB I saw something like I mentioned around 1.915 MHz. It then dropped down to around 1.913 MHz - and then it went away. I did make a recording - but I didn't get the best part due to the signal moving down a bit - from 1.915 to 1.913 MHz. Thanks, John AJ6BC 73 Frits W1FVB -- vbradio.wordpress.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] PRS-45A is alive!
Love to have known how long it was off, and how much of that 16 minutes was getting the tube degassed. -pete On Mon, Dec 8, 2014 at 7:11 PM, Bob Stewart b...@evoria.net wrote: Well, it's alive, and I even have 10MHz coming from it. It took about 16 minutes to go to lock. Is that good, or doesn't matter? Now I've got to put together a serial cable and see if I can talk to it and find out how it thinks it's doing. But, this is good! www.evoria.net/AE6RV/PRS-45A/2014-12-08%2020.51.33.jpg Hope you enjoy the wall decorations. =) Bob - AE6RV ___ 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] PRS-45A is alive!
Hi Pete, I don't have any way of knowing. I've asked the seller if he has a copy of the control software, and I don't like to go back with a bunch of petty questions like that. The next issue is adapting some serial port software i wrote to the protocol in the manual Magnus sent to see if I can pull the status codes out. That would probably tell me something. I have some tests I want to run immediately on my GPSDO and the KS to settle the question of which one can't keep time. After that, I'll power it down, lift its skirts and take some pics. It's pretty simple on the surface: a Cs Beam Tube, a main board, a microwave package with MTI 5Mhz OCXO, and the HV and LV power supplies. I don't intend to keep this thing running 24/7, but I have a question: Here in Houston, we have the occasional large thunderstorm and resulting short power outages. So, should I put a latching relay in the power stream to keep it off if I lose power? The budget is now officially busted, and a UPS is not going to happen for awhile. Santa's sleigh is now officially out of gas. Bob From: Pete Lancashire p...@petelancashire.com To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, December 8, 2014 11:46 PM Subject: Re: [time-nuts] PRS-45A is alive! Love to have known how long it was off, and how much of that 16 minutes was getting the tube degassed. -pete On Mon, Dec 8, 2014 at 7:11 PM, Bob Stewart b...@evoria.net wrote: Well, it's alive, and I even have 10MHz coming from it. It took about 16 minutes to go to lock. Is that good, or doesn't matter? Now I've got to put together a serial cable and see if I can talk to it and find out how it thinks it's doing. But, this is good! www.evoria.net/AE6RV/PRS-45A/2014-12-08%2020.51.33.jpg Hope you enjoy the wall decorations. =) Bob - AE6RV ___ 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] PRS-45A is alive!
Hi Bob, I think using a latching relay is a very good idea and prudent. Besides while it is reacquiring lock you would probably be busy resetting VCR's and so forth. BillWB6BNQ Bob Stewart wrote: Hi Pete, I don't have any way of knowing. I've asked the seller if he has a copy of the control software, and I don't like to go back with a bunch of petty questions like that. The next issue is adapting some serial port software i wrote to the protocol in the manual Magnus sent to see if I can pull the status codes out. That would probably tell me something. I have some tests I want to run immediately on my GPSDO and the KS to settle the question of which one can't keep time. After that, I'll power it down, lift its skirts and take some pics. It's pretty simple on the surface: a Cs Beam Tube, a main board, a microwave package with MTI 5Mhz OCXO, and the HV and LV power supplies. I don't intend to keep this thing running 24/7, but I have a question: Here in Houston, we have the occasional large thunderstorm and resulting short power outages. So, should I put a latching relay in the power stream to keep it off if I lose power? The budget is now officially busted, and a UPS is not going to happen for awhile. Santa's sleigh is now officially out of gas. Bob From: Pete Lancashire p...@petelancashire.com To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, December 8, 2014 11:46 PM Subject: Re: [time-nuts] PRS-45A is alive! Love to have known how long it was off, and how much of that 16 minutes was getting the tube degassed. -pete On Mon, Dec 8, 2014 at 7:11 PM, Bob Stewart b...@evoria.net wrote: Well, it's alive, and I even have 10MHz coming from it. It took about 16 minutes to go to lock. Is that good, or doesn't matter? Now I've got to put together a serial cable and see if I can talk to it and find out how it thinks it's doing. But, this is good! www.evoria.net/AE6RV/PRS-45A/2014-12-08%2020.51.33.jpg Hope you enjoy the wall decorations. =) Bob - AE6RV ___ 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.
