Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hi This is another of the many devices out there that pre-date the “modern” 180 degree phase modulation approach on WWVB. Getting one of these to run properly with the new modulation approach would take some major mods ….. Bob > On Oct 4, 2020, at 10:23 AM, Magnus Danielson wrote: > > Hi, > > I got a bit curious, so I dug up the manual (Available from Orolia that > Spectracom is part of): > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > It is apparent that the reference oscillator is actually free-running > but compared to the WWVB, so you manually tune it to make the > strip-chart become more of a flat line. > > This is interesting, because the receiver locks up another 10 MHz > oscillator. > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > that shows up as time-tags on the strip-chart, so it is not trivially so > that you just replace the simpler 10 MHz oscillator with the more > advanced, unless you can live with that modulation at which time it is a > fairlly trivial hack. You can be a bit more cunning to add hardware to > compensate the modulation, but I wonder if that is what is done. > > To figure it out, one has to pop the lid to figure out. That is however > not for me to do. > > Anyway, I thought the manual pointer and quick analysis would maybe be > appreciated. > > Good luck! > > Cheers, > Magnus > > On 2020-10-04 09:37, Kirk Bailey wrote: >> I ran across an interesting widget in my ongoing "find the bottom of the >> pile" task. Has a label indicating it was modified for "WWVB Continuous >> Monitored". I thought these were all for WWVB, so what does "Continuous >> Monitored" mean? See attached pic. If anyone is interested in being the >> new owner please contact me directly. >> >> Thanks, >> >> Kirk Bailey >> bai...@peak.org >> >> ___ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Agree with Bobs comment. The 180 degree phase flip killed all of the gear unless significant mods are done or the d-psk-r is used. Great old boxes though. Regards Paul WB8TSL On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: > Hi > > This is another of the many devices out there that pre-date the > “modern” 180 degree phase modulation approach on WWVB. Getting > one of these to run properly with the new modulation approach would take > some major mods ….. > > Bob > > > On Oct 4, 2020, at 10:23 AM, Magnus Danielson > wrote: > > > > Hi, > > > > I got a bit curious, so I dug up the manual (Available from Orolia that > > Spectracom is part of): > > > > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > > > It is apparent that the reference oscillator is actually free-running > > but compared to the WWVB, so you manually tune it to make the > > strip-chart become more of a flat line. > > > > This is interesting, because the receiver locks up another 10 MHz > > oscillator. > > > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > > that shows up as time-tags on the strip-chart, so it is not trivially so > > that you just replace the simpler 10 MHz oscillator with the more > > advanced, unless you can live with that modulation at which time it is a > > fairlly trivial hack. You can be a bit more cunning to add hardware to > > compensate the modulation, but I wonder if that is what is done. > > > > To figure it out, one has to pop the lid to figure out. That is however > > not for me to do. > > > > Anyway, I thought the manual pointer and quick analysis would maybe be > > appreciated. > > > > Good luck! > > > > Cheers, > > Magnus > > > > On 2020-10-04 09:37, Kirk Bailey wrote: > >> I ran across an interesting widget in my ongoing "find the bottom of the > >> pile" task. Has a label indicating it was modified for "WWVB Continuous > >> Monitored". I thought these were all for WWVB, so what does "Continuous > >> Monitored" mean? See attached pic. If anyone is interested in being > the > >> new owner please contact me directly. > >> > >> Thanks, > >> > >> Kirk Bailey > >> bai...@peak.org > >> > >> ___ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Is this why so many really high end devices are basically dumped on eBay now? I wondered why SRS device was so cheap now considering price of the SR620. It's too bad they don't work anymore. I'm sure when this happened it was a HUGE let down to many here that were using them? What's the best modern one of these for metrology use? Or has GNSS basically ended it? I'm very interested in your knowledge about these because I've really wondered how a modern one would compare to GNSS? Thanks, Bill .ılılı..ılılı. notfaded1 On Sun, Oct 4, 2020, 2:54 PM paul swed wrote: > Agree with Bobs comment. The 180 degree phase flip killed all of the gear > unless significant mods are done or the d-psk-r is used. Great old boxes > though. > Regards > Paul > WB8TSL > > On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: > > > Hi > > > > This is another of the many devices out there that pre-date the > > “modern” 180 degree phase modulation approach on WWVB. Getting > > one of these to run properly with the new modulation approach would take > > some major mods ….. > > > > Bob > > > > > On Oct 4, 2020, at 10:23 AM, Magnus Danielson > > wrote: > > > > > > Hi, > > > > > > I got a bit curious, so I dug up the manual (Available from Orolia that > > > Spectracom is part of): > > > > > > > > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > > > > > It is apparent that the reference oscillator is actually free-running > > > but compared to the WWVB, so you manually tune it to make the > > > strip-chart become more of a flat line. > > > > > > This is interesting, because the receiver locks up another 10 MHz > > > oscillator. > > > > > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > > > that shows up as time-tags on the strip-chart, so it is not trivially > so > > > that you just replace the simpler 10 MHz oscillator with the more > > > advanced, unless you can live with that modulation at which time it is > a > > > fairlly trivial hack. You can be a bit more cunning to add hardware to > > > compensate the modulation, but I wonder if that is what is done. > > > > > > To figure it out, one has to pop the lid to figure out. That is however > > > not for me to do. > > > > > > Anyway, I thought the manual pointer and quick analysis would maybe be > > > appreciated. > > > > > > Good luck! > > > > > > Cheers, > > > Magnus > > > > > > On 2020-10-04 09:37, Kirk Bailey wrote: > > >> I ran across an interesting widget in my ongoing "find the bottom of > the > > >> pile" task. Has a label indicating it was modified for "WWVB > Continuous > > >> Monitored". I thought these were all for WWVB, so what does > "Continuous > > >> Monitored" mean? See attached pic. If anyone is interested in being > > the > > >> new owner please contact me directly. > > >> > > >> Thanks, > > >> > > >> Kirk Bailey > > >> bai...@peak.org > > >> > > >> ___ > > >> time-nuts mailing list -- time-nuts@lists.febo.com > > >> To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >> and follow the instructions there. > > > ___ > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > and follow the instructions there. > > > > > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hi You *can* do all the work to get a WWVB based device running, it’s not impossible. Compared to a GNSS based device, the WWVB has a number of issues. The biggest is the twice a day ionosphere based disruption. There is no practical way to get around that. The net result of the this and the other stuff create a device that is several orders of magnitude worse than a GNSS system. To put some numbers on it, you get 10’s of ns of “wander” in a typical GPS setup over a day. On a WWVB setup you get 10’s of us ( yes microseconds) of movement at sunrise and sunset. You get as much as 10us between day and night. The normal operation process with a WWVB based setup was to look at data spaced 24 hours apart. Even then single digit us sort of systematic drift was not uncommon. That’s based on a *lot* of years using one of those Spectracom boxes ….. Bob > On Oct 4, 2020, at 7:41 PM, Bill Notfaded wrote: > > Is this why so many really high end devices are basically dumped on eBay > now? I wondered why SRS device was so cheap now considering price of the > SR620. It's too bad they don't work anymore. I'm sure when this happened > it was a HUGE let down to many here that were using them? What's the best > modern one of these for metrology use? Or has GNSS basically ended it? > I'm very interested in your knowledge about these because I've really > wondered how a modern one would compare to GNSS? > > Thanks, > > Bill > > .ılılı..ılılı. > notfaded1 > > On Sun, Oct 4, 2020, 2:54 PM paul swed wrote: > >> Agree with Bobs comment. The 180 degree phase flip killed all of the gear >> unless significant mods are done or the d-psk-r is used. Great old boxes >> though. >> Regards >> Paul >> WB8TSL >> >> On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: >> >>> Hi >>> >>> This is another of the many devices out there that pre-date the >>> “modern” 180 degree phase modulation approach on WWVB. Getting >>> one of these to run properly with the new modulation approach would take >>> some major mods ….. >>> >>> Bob >>> On Oct 4, 2020, at 10:23 AM, Magnus Danielson >>> wrote: Hi, I got a bit curious, so I dug up the manual (Available from Orolia that Spectracom is part of): >>> >> https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf It is apparent that the reference oscillator is actually free-running but compared to the WWVB, so you manually tune it to make the strip-chart become more of a flat line. This is interesting, because the receiver locks up another 10 MHz oscillator. Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, that shows up as time-tags on the strip-chart, so it is not trivially >> so that you just replace the simpler 10 MHz oscillator with the more advanced, unless you can live with that modulation at which time it is >> a fairlly trivial hack. You can be a bit more cunning to add hardware to compensate the modulation, but I wonder if that is what is done. To figure it out, one has to pop the lid to figure out. That is however not for me to do. Anyway, I thought the manual pointer and quick analysis would maybe be appreciated. Good luck! Cheers, Magnus On 2020-10-04 09:37, Kirk Bailey wrote: > I ran across an interesting widget in my ongoing "find the bottom of >> the > pile" task. Has a label indicating it was modified for "WWVB >> Continuous > Monitored". I thought these were all for WWVB, so what does >> "Continuous > Monitored" mean? See attached pic. If anyone is interested in being >>> the > new owner please contact me directly. > > Thanks, > > Kirk Bailey > bai...@peak.org > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. >>> >>> >>> ___ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >>> >> ___ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listin
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Bill Thats exactly why they showed up. Though I still tend to see silly prices. Heck serious humor you still see the GOES satellite Truetime DC468s for sale again at silly costs and thats been dead since 2001 or so. (Unless you have a GOES simulator) So you are right GPSDOs have taken their place pretty much. At least for a low cost investment we time-nuts get a very nice reference that's just there. But there are ways to make those old units work. Its a bit complicated and requires diving in pretty deeply. Some methods are simpler than others and if your closer they will work. I am in New England so its a lot tougher. WWVB can deliver a good signal. But GPSDOs have made me a bit lazy. Guess what I am listening to right now? The KD2BD wwvb costas loop receiver. There you go. Old habits die hard. Enjoy. Paul WB8TSL On Sun, Oct 4, 2020 at 8:21 PM Bill Notfaded wrote: > Is this why so many really high end devices are basically dumped on eBay > now? I wondered why SRS device was so cheap now considering price of the > SR620. It's too bad they don't work anymore. I'm sure when this happened > it was a HUGE let down to many here that were using them? What's the best > modern one of these for metrology use? Or has GNSS basically ended it? > I'm very interested in your knowledge about these because I've really > wondered how a modern one would compare to GNSS? > > Thanks, > > Bill > > .ılılı..ılılı. > notfaded1 > > On Sun, Oct 4, 2020, 2:54 PM paul swed wrote: > > > Agree with Bobs comment. The 180 degree phase flip killed all of the gear > > unless significant mods are done or the d-psk-r is used. Great old boxes > > though. > > Regards > > Paul > > WB8TSL > > > > On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: > > > > > Hi > > > > > > This is another of the many devices out there that pre-date the > > > “modern” 180 degree phase modulation approach on WWVB. Getting > > > one of these to run properly with the new modulation approach would > take > > > some major mods ….. > > > > > > Bob > > > > > > > On Oct 4, 2020, at 10:23 AM, Magnus Danielson > > > wrote: > > > > > > > > Hi, > > > > > > > > I got a bit curious, so I dug up the manual (Available from Orolia > that > > > > Spectracom is part of): > > > > > > > > > > > > > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > > > > > > > It is apparent that the reference oscillator is actually free-running > > > > but compared to the WWVB, so you manually tune it to make the > > > > strip-chart become more of a flat line. > > > > > > > > This is interesting, because the receiver locks up another 10 MHz > > > > oscillator. > > > > > > > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > > > > that shows up as time-tags on the strip-chart, so it is not trivially > > so > > > > that you just replace the simpler 10 MHz oscillator with the more > > > > advanced, unless you can live with that modulation at which time it > is > > a > > > > fairlly trivial hack. You can be a bit more cunning to add hardware > to > > > > compensate the modulation, but I wonder if that is what is done. > > > > > > > > To figure it out, one has to pop the lid to figure out. That is > however > > > > not for me to do. > > > > > > > > Anyway, I thought the manual pointer and quick analysis would maybe > be > > > > appreciated. > > > > > > > > Good luck! > > > > > > > > Cheers, > > > > Magnus > > > > > > > > On 2020-10-04 09:37, Kirk Bailey wrote: > > > >> I ran across an interesting widget in my ongoing "find the bottom of > > the > > > >> pile" task. Has a label indicating it was modified for "WWVB > > Continuous > > > >> Monitored". I thought these were all for WWVB, so what does > > "Continuous > > > >> Monitored" mean? See attached pic. If anyone is interested in > being > > > the > > > >> new owner please contact me directly. > > > >> > > > >> Thanks, > > > >> > > > >> Kirk Bailey > > > >> bai...@peak.org > > > >> > > > >> ___ > > > >> time-nuts mailing list -- time-nuts@lists.febo.com > > > >> To unsubscribe, go to > > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > >> and follow the instructions there. > > > > ___ > > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > > To unsubscribe, go to > > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > > and follow the instructions there. > > > > > > > > > ___ > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > To unsubscribe, go to > > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > and follow the instructions there. > > > > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. >
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
That's a very old WWVB receiver! * As you can see from that photo, that model was introduced before NIST was created from NBS in 1988 (see the "NBS OUTPUT" BNC). * The "WWVB Continuous Monitored" label appears to be a Tektronix internal calibration sticker. You can see the Tek "bug" logo (CRT side view overlaid with circular display overlaid with Tektronix written at an angle). I worked for Tektronix from 1987 through 2019, and that logo became obsolete about 30 years ago. You can see that the cal sticker is marked "Special Information", and I interpret this as a note that this instrument was used for continuous WWVB monitoring and did not need to be calibrated. * So my guess is that this instrument was originally used at a Tektronix company calibration lab. This could have been at the company headquarters in Beaverton, Oregon, one of the many Tektronix calibration labs located at field offices in the US and Canada (there were two large such labs in Texas in the 1980's), or at one of their worldwide service centers. * As noted by other posters, this model is incompatible with the current WWVB BPSK modulation. See: * https://en.wikipedia.org/wiki/Spectracom#WWVB_changes_affect_early_products * http://maxmcarter.com/rubidium/2012_mod/index.html (search for "8161" on that page for confirmation that these changes work) -- Bill Byrom N5BB On Sun, Oct 4, 2020, at 6:41 PM, Bill Notfaded wrote: > Is this why so many really high end devices are basically dumped on eBay > now? I wondered why SRS device was so cheap now considering price of the > SR620. It's too bad they don't work anymore. I'm sure when this happened > it was a HUGE let down to many here that were using them? What's the best > modern one of these for metrology use? Or has GNSS basically ended it? > I'm very interested in your knowledge about these because I've really > wondered how a modern one would compare to GNSS? > > Thanks, > > Bill > > .ılılı..ılılı. > notfaded1 > > On Sun, Oct 4, 2020, 2:54 PM paul swed wrote: > > > Agree with Bobs comment. The 180 degree phase flip killed all of the gear > > unless significant mods are done or the d-psk-r is used. Great old boxes > > though. > > Regards > > Paul > > WB8TSL > > > > On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: > > > > > Hi > > > > > > This is another of the many devices out there that pre-date the > > > “modern” 180 degree phase modulation approach on WWVB. Getting > > > one of these to run properly with the new modulation approach would take > > > some major mods ….. > > > > > > Bob > > > > > > > On Oct 4, 2020, at 10:23 AM, Magnus Danielson > > > wrote: > > > > > > > > Hi, > > > > > > > > I got a bit curious, so I dug up the manual (Available from Orolia that > > > > Spectracom is part of): > > > > > > > > > > > > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > > > > > > > It is apparent that the reference oscillator is actually free-running > > > > but compared to the WWVB, so you manually tune it to make the > > > > strip-chart become more of a flat line. > > > > > > > > This is interesting, because the receiver locks up another 10 MHz > > > > oscillator. > > > > > > > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > > > > that shows up as time-tags on the strip-chart, so it is not trivially > > so > > > > that you just replace the simpler 10 MHz oscillator with the more > > > > advanced, unless you can live with that modulation at which time it is > > a > > > > fairlly trivial hack. You can be a bit more cunning to add hardware to > > > > compensate the modulation, but I wonder if that is what is done. > > > > > > > > To figure it out, one has to pop the lid to figure out. That is however > > > > not for me to do. > > > > > > > > Anyway, I thought the manual pointer and quick analysis would maybe be > > > > appreciated. > > > > > > > > Good luck! > > > > > > > > Cheers, > > > > Magnus > > > > > > > > On 2020-10-04 09:37, Kirk Bailey wrote: > > > >> I ran across an interesting widget in my ongoing "find the bottom of > > the > > > >> pile" task. Has a label indicating it was modified for "WWVB > > Continuous > > > >> Monitored". I thought these were all for WWVB, so what does > > "Continuous > > > >> Monitored" mean? See attached pic. If anyone is interested in being > > > the > > > >> new owner please contact me directly. > > > >> > > > >> Thanks, > > > >> > > > >> Kirk Bailey > > > >> bai...@peak.org > > > >> > > > >> ___ > > > >> time-nuts mailing list -- time-nuts@lists.febo.com > > > >> To unsubscribe, go to > > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > >> and follow the instructions there. > > > > ___ > > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > > To unsubscribe, go to > > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
> On a WWVB setup you get 10âs of us ( yes microseconds) of movement at > sunrise and sunset. You get as much as 10us between day and night. Somehow, I was thinking that WWVB was ground wave and wouldn't be effected by changes in the height of the ionosphere. Am I totally out of it, or is 10s of uSec just a lot better than the day/night shift you get with WWV? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hi, On 2020-10-05 11:20, Hal Murray wrote: >> On a WWVB setup you get 10’s of us ( yes microseconds) of movement at >> sunrise and sunset. You get as much as 10us between day and night. > Somehow, I was thinking that WWVB was ground wave and wouldn't be effected by > changes in the height of the ionosphere. Am I totally out of it, or is 10s > of > uSec just a lot better than the day/night shift you get with WWV? You will for sure see a mix of ground wave and ionspheric reflection, and those will vector sum. Depending on your distance your milage may vary. The same is seen at 77,5 kHz (DCF77) and 100 kHz (LORAN-C). The solar flare effect documented in the 8161 manual is for sure an ionspheric reflection effect. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
On 10/5/20 3:59 AM, Magnus Danielson wrote: Hi, On 2020-10-05 11:20, Hal Murray wrote: On a WWVB setup you get 10’s of us ( yes microseconds) of movement at sunrise and sunset. You get as much as 10us between day and night. Somehow, I was thinking that WWVB was ground wave and wouldn't be effected by changes in the height of the ionosphere. Am I totally out of it, or is 10s of uSec just a lot better than the day/night shift you get with WWV? You will for sure see a mix of ground wave and ionspheric reflection, and those will vector sum. Depending on your distance your milage may vary. The same is seen at 77,5 kHz (DCF77) and 100 kHz (LORAN-C). The solar flare effect documented in the 8161 manual is for sure an ionspheric reflection effect. And, just as with Omega (10-15 kHz) the height of the ionosphere changes the effective height of the "waveguide" through which the surface wave propagates. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hi The height of the ionosphere changes night to day. That changes the effective propagation distance. As the day/night (or night/day) transition point crosses the path between you and WWVB the two “modes” compete with each other. They can do fun stuff like cancel out the signal entirely. If you watch the 60 KHz on a ’scope as all this goes on, the “slip” is enough to make it unclear which edge is which. ( = it slips a large fraction of / more than one cycle). At 60 KHz, one cycle of slip gets you 16.7 us. Indeed, just how much trouble you have depends a lot on where you are. In downtown Ft Collins, I doubt you see much slip at all :). Here on the east coast, you see cycles. Even back in Kansas things got pretty crazy and that’s not a super long path sort of thing. Our normal approach with WWVB was to check it at some specific time of day. You only “used” the data after it had made sense for at least three days running. For anything important, the target was five days running. Loran-C was a better alternative back then, if keeping your reference on frequency was the objective. Even with Loran, I would typically use more than one day’s worth of observations …. Bob > On Oct 5, 2020, at 5:20 AM, Hal Murray wrote: > > >> On a WWVB setup you get 10’s of us ( yes microseconds) of movement at >> sunrise and sunset. You get as much as 10us between day and night. > > Somehow, I was thinking that WWVB was ground wave and wouldn't be effected by > changes in the height of the ionosphere. Am I totally out of it, or is 10s > of > uSec just a lot better than the day/night shift you get with WWV? > > -- > These are my opinions. I hate spam. > > > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hal and Magnus its pretty interesting. WWVB is indeed a skywave behavior further out and at night. It exactly behaves like LORAN C and DCF and others. But during the day I think it generally behaves like ground wave from what I have experienced. What seems to be interesting is that the day to day is somewhat repeatable. There was a NIST and HP document back in the 1960-70s time ( Think its in the hp vlf117 manual also)that talks about day to day use for longer measurement periods. I was surprised by the details. Also consider the time frame most oscillators were low stability back then and the Cesiums were coming into play. Fun history. Regards Paul On Mon, Oct 5, 2020 at 8:18 AM Magnus Danielson wrote: > Hi, > > On 2020-10-05 11:20, Hal Murray wrote: > >> On a WWVB setup you get 10’s of us ( yes microseconds) of movement at > >> sunrise and sunset. You get as much as 10us between day and night. > > Somehow, I was thinking that WWVB was ground wave and wouldn't be > effected by > > changes in the height of the ionosphere. Am I totally out of it, or is > 10s of > > uSec just a lot better than the day/night shift you get with WWV? > > You will for sure see a mix of ground wave and ionspheric reflection, > and those will vector sum. Depending on your distance your milage may > vary. The same is seen at 77,5 kHz (DCF77) and 100 kHz (LORAN-C). The > solar flare effect documented in the 8161 manual is for sure an > ionspheric reflection effect. > > Cheers, > Magnus > > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
The 45 degree phase shift was a form of identification for WWVB and also served as a marker for chart recorders. The shift occurred from 10-minutes past the hour until 15 minutes past the hour. Before GPS came along, WWVB was my main frequency standard/reference. I had two Gertsch RLF devices and a "thumper" chart recorder. It was really a lot of grief trying to keep my relatively poor crystal oscillators on frequency. If I was able to see the 45-degree shift I felt as though I was really accomplishing something. :] I now have two DATUM 9390-52054 GPS units. GPS has really spoiled me! Up until the phase shift was added I used a Symmetricom 8170, not so much as a frequency reference, but as a clock in my shoppe. The 8170 is still running, but displays some strange combination of numbers that actually tell me the status of it trying to set. I suppose I should build a de-psk-er thingy, but I lost the paper work on how to do it.The 8170 presently serves as a night lite. Burt, K6OQK At 08:36 AM 10/4/2020, someone wrote: Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > that shows up as time-tags on the strip-chart, so it is not trivially... Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Burt I like it the "thumpers". The really annoying chart recorders I tend to disconnect. Imagine 2-3! I use a software recorder these days. Quite and consumes 10 X the power but no actual paper. Can't find that anymore at a price you might care to pay for. My other favorite box is the Gertch RLF. Not sure why it caught my eye on the floor at a hamfest but it did and what a bargain with a nice xtal filter. Have to love the RTL logic. We recently republished the details on the new improved dpskr here on time-nuts June approx. Do a search. It does make those old boxes work again without any internal mods. It also handles the fast and slow code. As Bob says you can get interesting accuracy over several days as the papers say even with the propagation. Regards Paul WB8TSL On Mon, Oct 5, 2020 at 11:59 AM Burt I. Weiner wrote: > The 45 degree phase shift was a form of identification for WWVB and > also served as a marker for chart recorders. The shift occurred from > 10-minutes past the hour until 15 minutes past the hour. > > Before GPS came along, WWVB was my main frequency > standard/reference. I had two Gertsch RLF devices and a "thumper" > chart recorder. It was really a lot of grief trying to keep my > relatively poor crystal oscillators on frequency. If I was able to > see the 45-degree shift I felt as though I was really accomplishing > something. :] I now have two DATUM 9390-52054 GPS units. GPS has > really spoiled me! > > Up until the phase shift was added I used a Symmetricom 8170, not so > much as a frequency reference, but as a clock in my shoppe. The 8170 > is still running, but displays some strange combination of numbers > that actually tell me the status of it trying to set. I suppose I > should build a de-psk-er thingy, but I lost the paper work on how to > do it.The 8170 presently serves as a night lite. > > Burt, K6OQK > > At 08:36 AM 10/4/2020, someone wrote: > >Now, there is a 45 degree (2.1 micro) modulation on the WWVB > >signal, > that shows up as time-tags on the strip-chart, so it is > >not trivially... > > Burt I. Weiner Associates > Broadcast Technical Services > Glendale, California U.S.A. > b...@att.net > K6OQK > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver -, Oscillator" for WWVB (and question...)
jimlux wrote : > And, just as with Omega (10-15 kHz) the height of the ionosphere > changes the effective height of the "waveguide" through which > the surface wave propagates. Exactly! Folks, this isn't simple "reflections" between the earth and the ionosphere. At VLF frequencies the wavelength is comparable to the height of the ionosphere (D layer, 70-90 km above earth's surface), so we have "waveguide propagation" in the "earth-ionosphere waveguide". The WWVB phase changes occurring during sunrise and sunset transitions are caused by the change in the dimensions of the waveguide. Quite a different situation from what we are used to at HF/VHF. ... Martin VE3OAT ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Hi You *are* talking about a 60 KHz sine wave when playing with WWVB. The typical receiver had a fairly narrow passband. This generally was accomplished with both high Q tuned circuits and a crystal filter. The typical antenna loop antenna also had a fairly high Q tune on it. Even if the signal was perfect, the receiving setup would have struggled once you got into the small fractions of a cycle sort of region …. For that matter, the matching network at the base of each of the transmit antennas has some pretty big tuned elements in it. They most certainly “chug” around any time the “breeze” blows in Colorado ( = most of the time …. :) ). Propagation at 60 KHz is also impacted by the weather. Push a cold front with a bunch of thunderheads into the path and you get a blip in the delay. Lots of other things get into that mix as well. Lots of variables ….. Bob > On Oct 5, 2020, at 9:52 AM, paul swed wrote: > > Hal and Magnus its pretty interesting. WWVB is indeed a skywave behavior > further out and at night. It exactly behaves like LORAN C and DCF and > others. But during the day I think it generally behaves like ground wave > from what I have experienced. What seems to be interesting is that the day > to day is somewhat repeatable. There was a NIST and HP document back in the > 1960-70s time ( Think its in the hp vlf117 manual also)that talks about day > to day use for longer measurement periods. I was surprised by the details. > Also consider the time frame most oscillators were low stability back then > and the Cesiums were coming into play. > Fun history. > Regards > Paul > > On Mon, Oct 5, 2020 at 8:18 AM Magnus Danielson wrote: > >> Hi, >> >> On 2020-10-05 11:20, Hal Murray wrote: On a WWVB setup you get 10’s of us ( yes microseconds) of movement at sunrise and sunset. You get as much as 10us between day and night. >>> Somehow, I was thinking that WWVB was ground wave and wouldn't be >> effected by >>> changes in the height of the ionosphere. Am I totally out of it, or is >> 10s of >>> uSec just a lot better than the day/night shift you get with WWV? >> >> You will for sure see a mix of ground wave and ionspheric reflection, >> and those will vector sum. Depending on your distance your milage may >> vary. The same is seen at 77,5 kHz (DCF77) and 100 kHz (LORAN-C). The >> solar flare effect documented in the 8161 manual is for sure an >> ionspheric reflection effect. >> >> Cheers, >> Magnus >> >> >> >> ___ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Which makes it a whole lot more fun then the lazy person's GPSDO. It is interesting to watch and listen. You do see things that are odd and explained. But sometimes it makes no sense at all. Omega was mentioned earlier. I barely started to tinker with it and they killed it off. We had a large receiver onboard the ship. But back to the 8161. Regards Paul WB8TSL On Mon, Oct 5, 2020 at 3:03 PM Bob kb8tq wrote: > Hi > > You *are* talking about a 60 KHz sine wave when playing with WWVB. The > typical receiver had a fairly narrow passband. This generally was > accomplished > with both high Q tuned circuits and a crystal filter. The typical antenna > loop antenna > also had a fairly high Q tune on it. Even if the signal was perfect, the > receiving > setup would have struggled once you got into the small fractions of a > cycle sort of > region …. > > For that matter, the matching network at the base of each of the transmit > antennas > has some pretty big tuned elements in it. They most certainly “chug” > around any > time the “breeze” blows in Colorado ( = most of the time …. :) ). > > Propagation at 60 KHz is also impacted by the weather. Push a cold front > with a > bunch of thunderheads into the path and you get a blip in the delay. Lots > of other > things get into that mix as well. > > Lots of variables ….. > > Bob > > > On Oct 5, 2020, at 9:52 AM, paul swed wrote: > > > > Hal and Magnus its pretty interesting. WWVB is indeed a skywave behavior > > further out and at night. It exactly behaves like LORAN C and DCF and > > others. But during the day I think it generally behaves like ground wave > > from what I have experienced. What seems to be interesting is that the > day > > to day is somewhat repeatable. There was a NIST and HP document back in > the > > 1960-70s time ( Think its in the hp vlf117 manual also)that talks about > day > > to day use for longer measurement periods. I was surprised by the > details. > > Also consider the time frame most oscillators were low stability back > then > > and the Cesiums were coming into play. > > Fun history. > > Regards > > Paul > > > > On Mon, Oct 5, 2020 at 8:18 AM Magnus Danielson > wrote: > > > >> Hi, > >> > >> On 2020-10-05 11:20, Hal Murray wrote: > On a WWVB setup you get 10’s of us ( yes microseconds) of movement > at > sunrise and sunset. You get as much as 10us between day and night. > >>> Somehow, I was thinking that WWVB was ground wave and wouldn't be > >> effected by > >>> changes in the height of the ionosphere. Am I totally out of it, or is > >> 10s of > >>> uSec just a lot better than the day/night shift you get with WWV? > >> > >> You will for sure see a mix of ground wave and ionspheric reflection, > >> and those will vector sum. Depending on your distance your milage may > >> vary. The same is seen at 77,5 kHz (DCF77) and 100 kHz (LORAN-C). The > >> solar flare effect documented in the 8161 manual is for sure an > >> ionspheric reflection effect. > >> > >> Cheers, > >> Magnus > >> > >> > >> > >> ___ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > >> > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
