Re: [time-nuts] FMT
Hey Henry Looks like your W1AW 40m numbers are in line with the others. I just checked my audio wave file with spectran, and the 40 meter signal was strong and stable. Joe (W1AW station manager)said he would post the results to the W1AW/FMT website soon, so we will wait and see if it is the same numbers as he gave me today in his email. Connie K5CM -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Henry Knoepfle Sent: Thursday, December 28, 2006 9:47 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FMT Interesting! My numbers: 160: 1854317.9 80: 3587117.6 40: 7308806.0 Henry KB7NIE On 12/28/06, Connie Marshall <[EMAIL PROTECTED]> wrote: > Hi Bill, > > Several others have now said they were off by 1 Hz on 40m. Possibly Joe ( > W1AW Station manager) typed the frequency wrong to my email, or W1AW > measured the freq incorrectly that night or as John mentioned there was a > artifact from the transmitter, or the Doppler was indeed that bad. I still > need to go back and look and my audio file with Spectran again. > > As I mentioned in an earlier email I was only off by .07 Hz on the WA6ZTY > run so I tend to think my system was working properly on 40m hmm. > > Connie > K5CM > > -Original Message- > From: Bill Tracey [mailto:[EMAIL PROTECTED] > Sent: Thursday, December 28, 2006 5:41 PM > To: [EMAIL PROTECTED]; Discussion of precise time and frequency > measurement; Time-Nuts > Subject: Re: [time-nuts] FMT > > > Very interesting - the measurements I submitted were: > > 160: 1854317.63 > 80: 3857117.47 > 40: 7038806.11 > > 40 (west coast): 7028351.61 > > I too got a >1hz high error on W1AW on 40. As I recall, the data had a > double peak in it - think I picked the stronger peak which apparently was > the wrong one. Apparently the propagation on 40 was interesting when the > test was run. > > Cheers, > > Bill (kd5tfd) > > At 02:25 PM 12/28/2006, Connie Marshall wrote: > > >Here are the W1AW FMT Numbers I just received from Joe, NJ1Q (W1AW > Station > >Manager) > >160m - 1854317.5 Hz > >80m - 3587117.5 > >40m - 7038804.9 Hz > > > >My copy of W1AW: > >160M 1854317.77 Hz > > 80M 3587117.95 Hz > > 40M 7038806.03 Hz > >I missed the 40m W1AW frequency by 1 Hz for some reason Hmm.. I > will > >go back and replay my audio file and see if I made a math mistake some > >where. > > > >My copy of WA6ZTY > >40M - 7028351.545 Hz > > > >Connie > >K5CM > >___ > >time-nuts mailing list > >time-nuts@febo.com > >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FMT
Interesting! My numbers: 160: 1854317.9 80: 3587117.6 40: 7308806.0 Henry KB7NIE On 12/28/06, Connie Marshall <[EMAIL PROTECTED]> wrote: > Hi Bill, > > Several others have now said they were off by 1 Hz on 40m. Possibly Joe ( > W1AW Station manager) typed the frequency wrong to my email, or W1AW > measured the freq incorrectly that night or as John mentioned there was a > artifact from the transmitter, or the Doppler was indeed that bad. I still > need to go back and look and my audio file with Spectran again. > > As I mentioned in an earlier email I was only off by .07 Hz on the WA6ZTY > run so I tend to think my system was working properly on 40m hmm. > > Connie > K5CM > > -Original Message- > From: Bill Tracey [mailto:[EMAIL PROTECTED] > Sent: Thursday, December 28, 2006 5:41 PM > To: [EMAIL PROTECTED]; Discussion of precise time and frequency > measurement; Time-Nuts > Subject: Re: [time-nuts] FMT > > > Very interesting - the measurements I submitted were: > > 160: 1854317.63 > 80: 3857117.47 > 40: 7038806.11 > > 40 (west coast): 7028351.61 > > I too got a >1hz high error on W1AW on 40. As I recall, the data had a > double peak in it - think I picked the stronger peak which apparently was > the wrong one. Apparently the propagation on 40 was interesting when the > test was run. > > Cheers, > > Bill (kd5tfd) > > At 02:25 PM 12/28/2006, Connie Marshall wrote: > > >Here are the W1AW FMT Numbers I just received from Joe, NJ1Q (W1AW > Station > >Manager) > >160m - 1854317.5 Hz > >80m - 3587117.5 > >40m - 7038804.9 Hz > > > >My copy of W1AW: > >160M 1854317.77 Hz > > 80M 3587117.95 Hz > > 40M 7038806.03 Hz > >I missed the 40m W1AW frequency by 1 Hz for some reason Hmm.. I > will > >go back and replay my audio file and see if I made a math mistake some > >where. > > > >My copy of WA6ZTY > >40M - 7028351.545 Hz > > > >Connie > >K5CM > >___ > >time-nuts mailing list > >time-nuts@febo.com > >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FMT
Hi Bill, Several others have now said they were off by 1 Hz on 40m. Possibly Joe ( W1AW Station manager) typed the frequency wrong to my email, or W1AW measured the freq incorrectly that night or as John mentioned there was a artifact from the transmitter, or the Doppler was indeed that bad. I still need to go back and look and my audio file with Spectran again. As I mentioned in an earlier email I was only off by .07 Hz on the WA6ZTY run so I tend to think my system was working properly on 40m hmm. Connie K5CM -Original Message- From: Bill Tracey [mailto:[EMAIL PROTECTED] Sent: Thursday, December 28, 2006 5:41 PM To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement; Time-Nuts Subject: Re: [time-nuts] FMT Very interesting - the measurements I submitted were: 160: 1854317.63 80: 3857117.47 40: 7038806.11 40 (west coast): 7028351.61 I too got a >1hz high error on W1AW on 40. As I recall, the data had a double peak in it - think I picked the stronger peak which apparently was the wrong one. Apparently the propagation on 40 was interesting when the test was run. Cheers, Bill (kd5tfd) At 02:25 PM 12/28/2006, Connie Marshall wrote: >Here are the W1AW FMT Numbers I just received from Joe, NJ1Q (W1AW Station >Manager) >160m - 1854317.5 Hz >80m - 3587117.5 >40m - 7038804.9 Hz > >My copy of W1AW: >160M 1854317.77 Hz > 80M 3587117.95 Hz > 40M 7038806.03 Hz >I missed the 40m W1AW frequency by 1 Hz for some reason Hmm.. I will >go back and replay my audio file and see if I made a math mistake some >where. > >My copy of WA6ZTY >40M - 7028351.545 Hz > >Connie >K5CM >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FMT
Bill Tracey said the following on 12/28/2006 06:41 PM: > I too got a >1hz high error on W1AW on 40. As I recall, the data had a > double peak in it - think I picked the stronger peak which apparently was > the wrong one. Apparently the propagation on 40 was interesting when the > test was run. I have to admit that I screwed up royally this year and had a math error that threw all my results off by 70 to 100 Hz (stupid error -- getting my sideband math backwards). I'll get my results up on the web site soon, both "as submitted" and what they would have been with the correct math. But I wanted to mention that I also saw a double hump on 40M, with about 0.5 Hz separation. I wonder if it was an artifact of the transmitter, or one of propagation. As I understand it, the League this year used regular ham transceivers instead of the old Harris rigs. On 160 and 80 they had Ten-Tecs, and on 40 I think an Icom. John ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FMT
Very interesting - the measurements I submitted were: 160: 1854317.63 80: 3857117.47 40: 7038806.11 40 (west coast): 7028351.61 I too got a >1hz high error on W1AW on 40. As I recall, the data had a double peak in it - think I picked the stronger peak which apparently was the wrong one. Apparently the propagation on 40 was interesting when the test was run. Cheers, Bill (kd5tfd) At 02:25 PM 12/28/2006, Connie Marshall wrote: >Here are the W1AW FMT Numbers I just received from Joe, NJ1Q (W1AW Station >Manager) >160m - 1854317.5 Hz >80m - 3587117.5 >40m - 7038804.9 Hz > >My copy of W1AW: >160M 1854317.77 Hz > 80M 3587117.95 Hz > 40M 7038806.03 Hz >I missed the 40m W1AW frequency by 1 Hz for some reason Hmm.. I will >go back and replay my audio file and see if I made a math mistake some >where. > >My copy of WA6ZTY >40M - 7028351.545 Hz > >Connie >K5CM >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Digital PLL ICs, alternatives and digital loop filters
From: "Stephan Sandenbergh" <[EMAIL PROTECTED]> Subject: RE: [time-nuts] Digital PLL ICs, alternatives and digital loop filters Date: Thu, 28 Dec 2006 23:31:49 +0200 Message-ID: <[EMAIL PROTECTED]> > Hi Magnus, Hi Stephan, > Sorry for my delayed response, but I was a bit under resourced on e-mail > facilities during the festive season. No worries. You answer in the same decade it's good. > > Go and get Floyd Garners "Phaselock Techniques". The reference and very > > worth reading. I have other books to recommend too. The popular BEST book > > isn't as great, but can sometimes be a good reminder too, but Garners book > > beats it in my opinion. > > I haven't got any of the books you mentioned but I worked through Wolaver's > "Phase-Locked Loop Circuit Design" some time ago. It is probably a bit out > dated but it was the thinnest on the shelf :) Nonetheless, I thought it is > quite good and serve as a good intro to PLLs. It is not a bad book, but I view it as a complementary book to the others. You will however find it in my bookshelf both at home and at work. The Wolaver book is actually very good in describing certains aspects better than some other books I've seen. So it can be a good book to grasp some of the aspects, but the Gardner book is _very_ readable and is really strongly recommended since is also such a deep book in what it covers even if it is only sligthly thicker than Wolavers book (which uses larger pages). > I've seen two books by William Egan: "Phase-Lock Basics" and "Frequency > Synthesis by Phase Lock" on our library's shelves. Are you familiar with > these? Are they worthwhile? I haven't looked in them. There are gazillions of books, but if you have Wolaver, Gardner and Best you should be able to get clues from Wolaver and Best while Gardner rules. > > I prefer phase detectors which is more continous such as mixers, XOR or > > S-R style phase detectors. > > In this case the phase detector is purely digital so I guess the loop filter > could also be a purely digital IIR filter (or something?) I guess the only > limitation is the frequency at which the digital system could run. If your phase detector is a TIC, then IIR filter is certainly the way to go. Be carefull about the dynamics. The processing you need should usually be very small so it should not be a hard problem to solve. If you process of each PPS and only needs a handfull of multiplications and additions you can do almost arbitrary bitlengths even in a very poor CPU. My Cs beam is controlled by a 6809 CPU, which also takes care of the serial line I/O. Whiee! Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] TIC resolution impact on GPSDO's performance
On Thu, December 28, 2006 21:59, Jason Rabel said: >> Bjorn and I have a little project going where we use the CNC Allstar > receivers. >> They have the specific feature that their referens XO is at 10 MHz. This > will >> make it very easy to drop in a suitable oscillator. As it happends I see > that a >> FTS1200 and an Allstar receiver has showed up in my main rack during >> some >> unexplainable appearance in the lab yeasterday. It is not as much the > ability >> too hook it up as getting the receiver time to EFC solution into place. > I'm >> working on that right now, but it will involve a little bit of wizardy. >> The Allstar receivers have about 1 cm RMS of carrier noise which should > show up >> as about 33 ps RMS noise. It should be an interesting proof of concept > thing. > > > I have some SuperStar II receivers and they also have a 10 MHz TCXO on > them, > now Novatel makes them. > > http://www.novatel.com/products/superstar.htm > > If you search for the phrase "OEM GPS MODULE WITH SMA ANTENNA CABLE" on > eBay > you should be able to find them when the person lists more (none currently > show up). They appear to be OEM models with on a 4mb flash and not the > newer > 8mb flash so they can't be upgraded. I have lots of PDFs with info and > everything. The pinout is more or less the same as the Rockwell Jupiter 8 > boards. There is also an open-source GPS project that uses the chip on > these, however the project in its current state is less than stellar. > > I bought 5 boards (was cheaper because of shipping costs). If you want one > or two let me know, I'll sell them cheap. I only want to keep a couple for > myself, definitely don't need 5. > > Jason A Superstar would be just as good base for our little project. I think Doug Bakers receivers would do too (think at some point some model even had an coax connector for an external oscillator) but they are ofcause much more expensive than surplus ebay receivers. http://www.gpscreations.com/Products_Receivers.html Another interesting user of the Zarlink chipset is Meinberg. They have a menu of oscillators from TCXO, via OCXOs to Rb. http://www.meinberg.de/german/specs/gpsopt.htm Has anyone taken a deeper look into a GPS167? I would be surprised if they do not let the main oscillator drive the GPS. Their GPS jitter specification is very conservative. Did anyone measure one to look at actual performance. On the other hand, if you drive an NTP-server or similar application, there is really no need for a low ns PPS pulse, it is very much more interesting to have a say sub 1us PPS, with a great holdover for events like antenna/cable failures, buying you some days to get aware of and fix the problem. John, if you are interested in data on the FTS1000 family for your oscillator performance page http://www.febo.com/time-freq/hardware/specs.html there is some data in ftp://ftp.lysator.liu.se/~bg/time-nuts/FTS1200Doku.pdf Magnus with all his fancy equipment :-) should be able to do some real measurements in the coming months on the FTS1200 and some other lesser oscillators now sitting in his rack. -- Björn ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] Digital PLL ICs,alternatives and digital loop filters
Hi all, Thanks for all of the very helpful responses, links and advice. I'm very sorry that I couldn't participate in the discussion at the time but I was a bit under resourced on e-mail facilities during the festive season. The trend that I noted from your replies is that the different techniques for up-converting from 10MHz to 100MHz can be ranked as follows: (best noise performance first) 1. Pure Analogue PLL where two high quality OCXOs are slaved onto another. 2. Analog frequency multipliers (if the reference is of low enough phase noise) 3. Digital PLL This list is also, as expected, ranked in order of associated cost. My GPS disciplined 10MHz OCXO, an Oscilloquartz model 8788 has the following phase noise: 1Hz -100 dBc 10Hz -130 100Hz -152 1kHz -160 10kHz -165 100kHz -165 1MHz-165 >From your replies I take that I'll probably ruin this clean phase noise characteristic by trying to lock it digitally to another high quality 100MHz OCXO, since this kind of oscillator exceeds the performance of what is achievable with a digital PLL IC. In this case I would also have wasted good money on the 100MHz OCXO. It seems that the second best option (cost wise) would be to analog multiply the 8788's output to 100MHz. Theoretically, I would then sit with the original phase noise curved that is lifted by 20logN, where N=10, which is about 20dBs. Thus, I would start of at -80dBc @ 1Hz and end off with a -145dBc noise floor. (in real life I guess one would add another few dBs for noise added by the individual components) It also seems that the needed analog multipliers are a good start on one's way to a fully analog PLL - the mixer and loop filter could be added later if required. Could anyone point me to some analog frequency multiplier manufacturers? (Currently I am only familiar with Wenzel (thanks Bruce)) In the mean while, it is back to the books for me - I seriously need to catch up on some PLL theory. Regards, Stephan Sandenbergh. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Digital PLL ICs, alternatives and digital loop filters
Hi Magnus, Sorry for my delayed response, but I was a bit under resourced on e-mail facilities during the festive season. > Go and get Floyd Garners "Phaselock Techniques". The reference and very > worth reading. I have other books to recommend too. The popular BEST book > isn't as great, but can sometimes be a good reminder too, but Garners book > beats it in my opinion. I haven't got any of the books you mentioned but I worked through Wolaver's "Phase-Locked Loop Circuit Design" some time ago. It is probably a bit out dated but it was the thinnest on the shelf :) Nonetheless, I thought it is quite good and serve as a good intro to PLLs. I've seen two books by William Egan: "Phase-Lock Basics" and "Frequency Synthesis by Phase Lock" on our library's shelves. Are you familiar with these? Are they worthwhile? > I prefer phase detectors which is more continous such as mixers, XOR or > S-R style phase detectors. In this case the phase detector is purely digital so I guess the loop filter could also be a purely digital IIR filter (or something?) I guess the only limitation is the frequency at which the digital system could run. Cheers, Stephan Sandenbergh > -Original Message- > From: Magnus Danielson [mailto:[EMAIL PROTECTED] > Sent: 16 December 2006 10:02 PM > To: time-nuts@febo.com; [EMAIL PROTECTED] > Subject: Re: [time-nuts] Digital PLL ICs, alternatives and digital loop > filters > > From: "Stephan Sandenbergh" <[EMAIL PROTECTED]> > Subject: [time-nuts] Digital PLL ICs, alternatives and digital loop > filters > Date: Sat, 16 Dec 2006 20:52:25 +0200 > Message-ID: <[EMAIL PROTECTED]> > > > Hi, > > Hi Stephan, > > > Another question for today - I have checked out some digital PLL ICs > (more > > specifically the one's from AnalogDevices. It seems as if they've got > some > > pretty neat stuff.) As I mentioned in my previous mail: I want to lock a > > GPSDOs 10MHz to a 100MHz OCXO using some sort of PLL. I find the PLL ICs > > convenient because they've got everything that is needed already built- > in. > > Also, the phase detector and dividers are all optimised for low jitter. > > The type of phase detector is what I would worry about. See more below. > > > Can anyone give me some pointers regarding this? If I need a low noise > > 100MHz output, is the digital PLL and a 100MHz OCXO a good choice? I > guess > > that analog PLL techniques are better, but is it worth all that effort? > > Maybe I should look at PLL ICs from other manufacturers? > > Go and get Floyd Garners "Phaselock Techniques". The reference and very > worth > reading. I have other books to recommend too. The popular BEST book isn't > as > great, but can sometimes be a good reminder too, but Garners book beats it > in > my opinion. > > > Also, I'm slightly worried about the thermal instabilities inherent in > the > > analog loop filter that is required by these PLL ICs. Has anyone > > successfully chased the charge pumps output through a digital filter? > Or, is > > there a reason why this isn't done? > > Unless you have a high comparision frequency I would avoid chargepumps. > They > (risk) delay the correction until it has become large enought. This means > that > it will balance around the intended frequency with related phase drift. > I prefer phase detectors which is more continous such as mixers, XOR or S- > R > style phase detectors. > > An active loop filter is also my preference, but for some case I go for > passive > lag since it works well enought for some applications. Passive lags has > the > inherent downside that the loop gain converts the difference between non- > modulated frequency of the oscillator and tracked frequency into a phase > difference. Changes in temperature will show up as phase modulations. For > some > applications I don't care, but when I do there is no alternative to active > loop filter. An op-amp, two resistors and a capacitor isn't that bad > solution > when things comes around. > > Cheers, > Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] FMT
Here is the WA6ZTY tx frequency: 40 Meters - 7028351.47 Hz My reading: 7028351.54 Hz I'm only off by .07 Hz here, so I feel my system was calibrated OK. Not yet sure why my reading on W1AW 40m was so far off (1 Hz). Connie K5CM ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] TIC resolution impact on GPSDO's performance
> Bjorn and I have a little project going where we use the CNC Allstar receivers. > They have the specific feature that their referens XO is at 10 MHz. This will > make it very easy to drop in a suitable oscillator. As it happends I see that a > FTS1200 and an Allstar receiver has showed up in my main rack during some > unexplainable appearance in the lab yeasterday. It is not as much the ability > too hook it up as getting the receiver time to EFC solution into place. I'm > working on that right now, but it will involve a little bit of wizardy. > The Allstar receivers have about 1 cm RMS of carrier noise which should show up > as about 33 ps RMS noise. It should be an interesting proof of concept thing. I have some SuperStar II receivers and they also have a 10 MHz TCXO on them, now Novatel makes them. http://www.novatel.com/products/superstar.htm If you search for the phrase "OEM GPS MODULE WITH SMA ANTENNA CABLE" on eBay you should be able to find them when the person lists more (none currently show up). They appear to be OEM models with on a 4mb flash and not the newer 8mb flash so they can't be upgraded. I have lots of PDFs with info and everything. The pinout is more or less the same as the Rockwell Jupiter 8 boards. There is also an open-source GPS project that uses the chip on these, however the project in its current state is less than stellar. I bought 5 boards (was cheaper because of shipping costs). If you want one or two let me know, I'll sell them cheap. I only want to keep a couple for myself, definitely don't need 5. Jason ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-RB
I'm sure Lucent engineers spent quite a bit of effort designing that metal box to keep the rubidium temperature as low as possible for extended life. If the rubidium is used in a different enclosure pay special attention to thermal conditions as the life of the rubidium is reduced with increasing temperature. If it is warm to the touch while operating you are not getting the most useful life out of the unit. The LPRO manual shows this as the mean time before failure versus operating temperature: TempMTBF 20°C 68°F381,00043.5 yrs 25°C 77°F351,00040.1 yrs 30°C 86°F320,00036.5 yrs 40°C104°F 253,00028.9 yrs 50°C122°F 189,00021.6 yrs 60°C140°F 134,00015.3 yrs I ended up building by own controller and mounting it inside the Lucent box, removed their front panel and mounted the box to my front panel to keep the thermal design the same and take advantage of Lucent's thermal engineering. Have fun! Richard - Original Message - From: "Rex" <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" Sent: Thursday, December 28, 2006 1:28 AM Subject: Re: [time-nuts] Lucent RFG-RB > On Thu, 28 Dec 2006 21:49:59 +1300, Dr Bruce Griffiths > <[EMAIL PROTECTED]> wrote: > > >Rex wrote: > > >> The 15 MHz generation looks very similar to the other boad I described > >> in another message on an FRS-C unit. The active source again seems to > >> come from an Altera PLD. Maybe it divides 10 MHz by two, and (guess) > >> narrows the pulse for better 3rd harmonic? > > > >Narrowing the pulse width does little for the amplitude of the third > >harmonic component. > >There's already plenty with a 50% duty cycle square wave. > >A waveform with duty duty cycle of 1/6 has the same 3rd hamonic > >component amplitude as a 50% duty cycle waveform. > >Narrowing the pulse to a very small duty cycle tends to flatten the the > >frequency comb whilst reducing the amplitude of all components. > >see: > >http://www.wenzel.com/pdffiles/choose.pdf > > > >Bruce > > Yeah, the harmonic amplitudes vs pulse width chart in that Wenzel doc is > exactly what I was thinking about when I wrote. I didn't actually look > at it though. I see now 3rd is good at 50% and the other harmonics are > mostly low. Guess I was trying to find a reason why the source for the > 15 MHz filter seemed to be coming out of a PLD. Maybe it's doing other > more complicated functions that I haven't yet figured out, and divide by > 2 for the 10 MHz was just easy to throw in. Like I said, seems about > like the implementation I saw in that other board. Never did work out > all the PLD was doing there either. PLDs are hard to guess out. > > I guess, when I get around to powering it up, I can put a scope on the > signal at that point and see if it is just 5 MHz square. > > Good chance I'll just use the LPRO anyway and dump the rest of the box. > Can't think of a reason why I need 15 MHz and I can't see much else > useful in the rest of the supporting circuitry. > > The metal box is kind of interesting. > > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] FMT
Here are the W1AW FMT Numbers I just received from Joe, NJ1Q (W1AW Station Manager) 160m - 1854317.5 Hz 80m - 3587117.5 40m - 7038804.9 Hz My copy of W1AW: 160M 1854317.77 Hz 80M 3587117.95 Hz 40M 7038806.03 Hz I missed the 40m W1AW frequency by 1 Hz for some reason Hmm.. I will go back and replay my audio file and see if I made a math mistake some where. My copy of WA6ZTY 40M - 7028351.545 Hz Connie K5CM ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
Hi Richard, Thanks, your explanation sounds right from memory. However, I am somewhat amused at the complexity of the XO, given it's otherwise simple task. Maybe it is just over engineered, and there is no other function other then your explanation. Currently my XO serves as a good paper weight. Hopefully in time, this forum will flush out more detail on the RG and XO set. Gerald - Original Message - From: "Richard H McCorkle" <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" Sent: Friday, December 29, 2006 6:44 AM Subject: Re: [time-nuts] Lucent RFG-M-RG and XO > Back when these Lucent units were first appearing GPS had not yet been > implemented at the cell sites here in Alaska. The rubidium was too noisy > for > direct frequency synthesis, so the XO unit was phase locked to the > rubidium > to provide the long-term stability needed, and the XO output was > up-converted for the system clock. By using the XO to smooth the rubidium > output the phase noise in the system clock was reduced due to better > short-term stability in the XO. As I remember it (It's been a while) the > 10M > Rb disciplined the 10M XO, which was divided by 2, multiplied by 3, > filtered, and supplied as the 15M system clock. The XO was always > supplying > the 15M system clock, and "standby" just meant the XO was locked to the > rubidium, which was acting as the primary frequency reference. When the > rubidium failed the system alarm output went high, XO PLL went into hold, > the standby light on the XO extinguished, and the undisciplined XO became > the source until the rubidium could be replaced. The GPS connection didn't > appear until later units and disciplined the XO during normal operation, > with failover on extended GPS loss to disciplining the XO from the > rubidium. > Hope this helps in figuring out the why of the system connections. > > Have Fun! > Richard > > > - Original Message - > From: "John Ackermann N8UR" <[EMAIL PROTECTED]> > To: "Discussion of precise time and frequency measurement" > > Sent: Thursday, December 28, 2006 4:51 AM > Subject: Re: [time-nuts] Lucent RFG-M-RG and XO > > >> Thanks for the information, Gerald. >> >> Could the fault light without 10MHz input be as simple as the system >> reporting failure of the Rb? i.e., the XO unit working OK, but just >> reporting that the system wasn't operating properly. >> >> Like you, I'm having trouble sussing out just why this thing is designed >> as it is, which oscillator is primary, and why... >> >> John >> >> >> Gerald Molenkamp said the following on 12/28/2006 06:27 AM: >> > Some 5 years ago I recovered one of each, ( RFG-M-RG & RFG-M-XO ) from >> > a > Lucent CDMA BSC site here in Australia. Both units were only 12 months > old, > at that stage inter-connected via the J5 "interface" 10MHz out to 10MHz in > from the RG to XO respectively and of course 24 VDC. >> > >> > After some reverse engineering of the BSC, I never understood the >> > reason > for the REG-M-XO in the BSC as it required a 10 MHz input from the RG for > it > to operate properly, e.g. the fault LED off. The 15 MHz signal is the > synthesiser reference output that is fed into the BSC radio, > synchronisation > then propagates through the CDMA network, which I assume is used as one of > many Primary Reference clocks ( PRC ) for the network of many BSC's. My > assumption is that the XO is used as a back-up PRC in the event of RG > failure, or as part of the hold-over system, but this was questionable. >> >> ___ >> time-nuts mailing list >> time-nuts@febo.com >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
Back when these Lucent units were first appearing GPS had not yet been implemented at the cell sites here in Alaska. The rubidium was too noisy for direct frequency synthesis, so the XO unit was phase locked to the rubidium to provide the long-term stability needed, and the XO output was up-converted for the system clock. By using the XO to smooth the rubidium output the phase noise in the system clock was reduced due to better short-term stability in the XO. As I remember it (It's been a while) the 10M Rb disciplined the 10M XO, which was divided by 2, multiplied by 3, filtered, and supplied as the 15M system clock. The XO was always supplying the 15M system clock, and "standby" just meant the XO was locked to the rubidium, which was acting as the primary frequency reference. When the rubidium failed the system alarm output went high, XO PLL went into hold, the standby light on the XO extinguished, and the undisciplined XO became the source until the rubidium could be replaced. The GPS connection didn't appear until later units and disciplined the XO during normal operation, with failover on extended GPS loss to disciplining the XO from the rubidium. Hope this helps in figuring out the why of the system connections. Have Fun! Richard - Original Message - From: "John Ackermann N8UR" <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" Sent: Thursday, December 28, 2006 4:51 AM Subject: Re: [time-nuts] Lucent RFG-M-RG and XO > Thanks for the information, Gerald. > > Could the fault light without 10MHz input be as simple as the system > reporting failure of the Rb? i.e., the XO unit working OK, but just > reporting that the system wasn't operating properly. > > Like you, I'm having trouble sussing out just why this thing is designed > as it is, which oscillator is primary, and why... > > John > > > Gerald Molenkamp said the following on 12/28/2006 06:27 AM: > > Some 5 years ago I recovered one of each, ( RFG-M-RG & RFG-M-XO ) from a Lucent CDMA BSC site here in Australia. Both units were only 12 months old, at that stage inter-connected via the J5 "interface" 10MHz out to 10MHz in from the RG to XO respectively and of course 24 VDC. > > > > After some reverse engineering of the BSC, I never understood the reason for the REG-M-XO in the BSC as it required a 10 MHz input from the RG for it to operate properly, e.g. the fault LED off. The 15 MHz signal is the synthesiser reference output that is fed into the BSC radio, synchronisation then propagates through the CDMA network, which I assume is used as one of many Primary Reference clocks ( PRC ) for the network of many BSC's. My assumption is that the XO is used as a back-up PRC in the event of RG failure, or as part of the hold-over system, but this was questionable. > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] ARRL FMT
Yes, but was hoping someone might have the frequencies since it's after the deadline. I will check with Joe at the league and see if he will post the frequencies or make us wait till the letters come out hi hi. Connie -Original Message- From: Carl Walker [mailto:[EMAIL PROTECTED] Sent: Thursday, December 28, 2006 11:29 AM To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] ARRL FMT The result letters normally appear sometime in the middle to end of January. -Carl WA1RAJ On Thu, 2006-12-28 at 11:23 -0600, Connie Marshall wrote: > Has anyone received the results of the ARRL FMT yet. > > Connie > K5CM ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] ARRL FMT
Has anyone received the results of the ARRL FMT yet. Connie K5CM ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
In message <[EMAIL PROTECTED]>, Rex writes: >I agree. The more I learn about the system, the odder it seems. Before >looking at the RB, I would have guessed that the XO unit, with GPS, >would have been disciplining the Rb to use in hold-over. In the RB, I >don't see any signs of a connection to the C-field control and no >identifiable DAC, so I assume the RB runs standalone, with only the >factory alignment of the Rb. I didn't see anyway to get to the >adjustment for C-field on the LPRO without dismantling the whole box >either. The telecom "stratum-2" definition is defined to match a free-running Rb. (S1 = Cs, S3 = OCXO) Remember that for CDMA and telecoms in general, the phase is not relevant, only the frequency stability which has different short and long term requirements (Eyepatterns, vs. jitter-propagation). I don't know what stratum level CDMA base stations require, but S2 is not unlikely. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-RB
>From what I have read, the RB acts as the primary once it has warmed up and locked, and the XO goes into 'standby'. But if something happens to the RB then the XO switches to the primary. Still waiting for Lucent to verify my account. I guess it wouldn't hurt for someone else to register on their site. Then we can all start bugging them for documentation. Also waiting for that person on eBay to send me the pictures and info on the rest of the accessories. Jason > Does anyone know how these two units work together? I assume it must be > for redundancy, but it's hard to figure out just how it all works > together. I assume the Rb is intended to provide long-term holdover if > the GPS or XO fails. It'd sure be nice to find at least some > system-level documentation. > > John > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] New acquisition
Have ebay acquired a used HP10544A attached to a PC card HP 05328-20027. Plan to use it as an osc upgrade for a lest than "perfect" HP105B. Anyone have schematic, pinouts, function, etc of the card? Thanks LesK1YCM M0YCM M0YCM/6Y5 Pictures available direct on request PSC 45 Box 781 APO AE 09468 Dawn Cottage Norwood Harrogate HG3 1SD UK Telephones: Office 940-6456 Office +44-(0)1423-846-385 Home: +44-(0)1943-880-963 UK Cell +44-(0)7716-298-224 US Cell +1-240-425-7335 Jamaica+1-876-352-7504 ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
On Thu, 28 Dec 2006 08:51:24 -0500, John Ackermann N8UR <[EMAIL PROTECTED]> wrote: >Thanks for the information, Gerald. > >Could the fault light without 10MHz input be as simple as the system >reporting failure of the Rb? i.e., the XO unit working OK, but just >reporting that the system wasn't operating properly. > >Like you, I'm having trouble sussing out just why this thing is designed >as it is, which oscillator is primary, and why... > >John > I agree. The more I learn about the system, the odder it seems. Before looking at the RB, I would have guessed that the XO unit, with GPS, would have been disciplining the Rb to use in hold-over. In the RB, I don't see any signs of a connection to the C-field control and no identifiable DAC, so I assume the RB runs standalone, with only the factory alignment of the Rb. I didn't see anyway to get to the adjustment for C-field on the LPRO without dismantling the whole box either. There is a chance I am wrong about the lack of connection to the C-field pin. The board in the RB that I looked at does seem to be 3-layer, so visually tracing some of the signals can't be done. My measurements from the C-field pin didn't find any hint of a connection on the board. -Rex ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
Thanks for the information, Gerald. Could the fault light without 10MHz input be as simple as the system reporting failure of the Rb? i.e., the XO unit working OK, but just reporting that the system wasn't operating properly. Like you, I'm having trouble sussing out just why this thing is designed as it is, which oscillator is primary, and why... John Gerald Molenkamp said the following on 12/28/2006 06:27 AM: > Some 5 years ago I recovered one of each, ( RFG-M-RG & RFG-M-XO ) from a > Lucent CDMA BSC site here in Australia. Both units were only 12 months old, > at that stage inter-connected via the J5 "interface" 10MHz out to 10MHz in > from the RG to XO respectively and of course 24 VDC. > > After some reverse engineering of the BSC, I never understood the reason for > the REG-M-XO in the BSC as it required a 10 MHz input from the RG for it to > operate properly, e.g. the fault LED off. The 15 MHz signal is the > synthesiser reference output that is fed into the BSC radio, synchronisation > then propagates through the CDMA network, which I assume is used as one of > many Primary Reference clocks ( PRC ) for the network of many BSC's. My > assumption is that the XO is used as a back-up PRC in the event of RG > failure, or as part of the hold-over system, but this was questionable. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-RB
Thanks, Rex. Does anyone know how these two units work together? I assume it must be for redundancy, but it's hard to figure out just how it all works together. I assume the Rb is intended to provide long-term holdover if the GPS or XO fails. It'd sure be nice to find at least some system-level documentation. John Rex said the following on 12/28/2006 03:22 AM: > I just received a Lucent RFG-RB (no -m- in this one) rubidium unit eBay > buy from the lady in Atlanta. Thought I'd share a few notes on what it > is. Maybe some of this has already been covered -- I lost track of all > the emails. > > Like John, I immediately opened it up, haven't tried it yet, and won't > for a while. > > No GPS, as has been noted in the other messages, that seems to be in the > crystal unit. This one was made in 2000. Inside mine, the main component > is a Datum LPRO 102500. Seems to be functionally identical to the one in > the manual here: > http://www.symmetricom.com/media/pdf/manuals/man-lpro.pdf > > Box front panel: > 3 sma's - TP (J1), 10 MHz RF Out (J2), 15 MHz Out (J4) > 3 db9's - +24V (P1), Alarm (J3), Interface (J5) > 3 led's - Fault, Stby, On > > Seems the +24V connector only uses two pins: 1 = +24, 2 = return/gnd > I assume those two are all that's needed to make it run. > > Main board is made by Efratom. > > I don't see any connection to the rubidium C-field pin so I don't think > there is any adjustment through the main board, just the adjustment thru > the case of the LPRO. > > With some tracing, I can't figure where the 10 MHz output (sma) comes > from. I assume it is functional, but haven't applied power yet. > > The 15 MHz generation looks very similar to the other boad I described > in another message on an FRS-C unit. The active source again seems to > come from an Altera PLD. Maybe it divides 10 MHz by two, and (guess) > narrows the pulse for better 3rd harmonic? Anyway, then it seems to go > through a series resonant LC, with a trimmer on the C. Then thru the 15 > MHz filter, two stages of amplification, and a MCL low-pass filter to > the sma. > > BITE signal from the LPRO goes somewhere so I assume it is at least part > of the alarm connector output. > > If anyone finds or works out the pins on the alarm and interface > connectors, I'd eb interested to hear about it. > > So there we are for now. Quick first look without even trying it yet. > Assuming it works, the LPRO was probably worth my $130 investment. Hope > some of my comments helps someone. > > -Rex > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-M-RG and XO
In message <[EMAIL PROTECTED]>, "Gerald Molenkamp" writes: >After some reverse engineering of the BSC, I never understood the >reason for the REG-M-XO in the BSC as it required a 10 MHz input >from the RG for it to operate properly, e.g. the fault LED off. [...] The XO may simply be there to be able to detect faults in the Rb, and possibly to implement a "if it works, it works" hold-over capability. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] T&F Equipment
Hello Time Nuts, For private matters I will stop my hobby at the frequency field. I think to sell my instruments if any is interested, I can put it on ebay or sell direct. The equipment I have is; HP5061 (not working HV 2.5 kV defective condition of the high Performance tube is unknown), Tracor Rubidium 305D, Tracor 895A Phase comparator, HP 3570B Interval counter +HPIB, SR620 Interval counter, HP3545 counter,Marconi 2305 High Pref. Modulation meter, Marconi 2019 signal Generator,Marconi 2440 20 GHz counter, Leitch CSD5300 Master Clock, Yokogawa AG1200 ARB Generator, Yokogawa DL5140 500MHz 4ch digital Oscilloscope. B&K 2033 High resolution signal analyser. I think above instruments could be used for frequency measurements. If interested please contact me a [EMAIL PROTECTED] I will still working on the T&F field for my work using CS clocks and TWSTFT transfer. You can't beat it at home. Best regards, Erik Kroon ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] Lucent RFG-M-RG and XO
Some 5 years ago I recovered one of each, ( RFG-M-RG & RFG-M-XO ) from a Lucent CDMA BSC site here in Australia. Both units were only 12 months old, at that stage inter-connected via the J5 "interface" 10MHz out to 10MHz in from the RG to XO respectively and of course 24 VDC. After some reverse engineering of the BSC, I never understood the reason for the REG-M-XO in the BSC as it required a 10 MHz input from the RG for it to operate properly, e.g. the fault LED off. The 15 MHz signal is the synthesiser reference output that is fed into the BSC radio, synchronisation then propagates through the CDMA network, which I assume is used as one of many Primary Reference clocks ( PRC ) for the network of many BSC's. My assumption is that the XO is used as a back-up PRC in the event of RG failure, or as part of the hold-over system, but this was questionable. For as many years as I have had both units, I have tried to obtain specific module data from vendors down here, but unfortunately none is available. However the LPRO Rubidium unit with-in the RFG-M-RG unit is an absolute ripper on it's own. I do have the following pin-out data for the interface J5 from the RG to XO:- RB DB9 Pin No.XO DB9M Pin No. 15 33 RG & XO P1 DB9 power connector 1+24vdc 20 vdc The RG requires approx. 1.3 A @ +24vdc at start-up, the current drops to approx. 600mA. The XO requires 300mA, but drops slightly after warm-up. If any one has more data, please let the audience know. I am keen to understand the need for a Rubidium PRC to disciple an oven controlled oscillator ( XO )? Gerald ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-RB
On Thu, 28 Dec 2006 21:49:59 +1300, Dr Bruce Griffiths <[EMAIL PROTECTED]> wrote: >Rex wrote: >> The 15 MHz generation looks very similar to the other boad I described >> in another message on an FRS-C unit. The active source again seems to >> come from an Altera PLD. Maybe it divides 10 MHz by two, and (guess) >> narrows the pulse for better 3rd harmonic? > >Narrowing the pulse width does little for the amplitude of the third >harmonic component. >There's already plenty with a 50% duty cycle square wave. >A waveform with duty duty cycle of 1/6 has the same 3rd hamonic >component amplitude as a 50% duty cycle waveform. >Narrowing the pulse to a very small duty cycle tends to flatten the the >frequency comb whilst reducing the amplitude of all components. >see: >http://www.wenzel.com/pdffiles/choose.pdf > >Bruce Yeah, the harmonic amplitudes vs pulse width chart in that Wenzel doc is exactly what I was thinking about when I wrote. I didn't actually look at it though. I see now 3rd is good at 50% and the other harmonics are mostly low. Guess I was trying to find a reason why the source for the 15 MHz filter seemed to be coming out of a PLD. Maybe it's doing other more complicated functions that I haven't yet figured out, and divide by 2 for the 10 MHz was just easy to throw in. Like I said, seems about like the implementation I saw in that other board. Never did work out all the PLD was doing there either. PLDs are hard to guess out. I guess, when I get around to powering it up, I can put a scope on the signal at that point and see if it is just 5 MHz square. Good chance I'll just use the LPRO anyway and dump the rest of the box. Can't think of a reason why I need 15 MHz and I can't see much else useful in the rest of the supporting circuitry. The metal box is kind of interesting. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Lucent RFG-RB
Rex wrote: > I just received a Lucent RFG-RB (no -m- in this one) rubidium unit eBay > buy from the lady in Atlanta. Thought I'd share a few notes on what it > is. Maybe some of this has already been covered -- I lost track of all > the emails. > > Like John, I immediately opened it up, haven't tried it yet, and won't > for a while. > > No GPS, as has been noted in the other messages, that seems to be in the > crystal unit. This one was made in 2000. Inside mine, the main component > is a Datum LPRO 102500. Seems to be functionally identical to the one in > the manual here: > http://www.symmetricom.com/media/pdf/manuals/man-lpro.pdf > > Box front panel: > 3 sma's - TP (J1), 10 MHz RF Out (J2), 15 MHz Out (J4) > 3 db9's - +24V (P1), Alarm (J3), Interface (J5) > 3 led's - Fault, Stby, On > > Seems the +24V connector only uses two pins: 1 = +24, 2 = return/gnd > I assume those two are all that's needed to make it run. > > Main board is made by Efratom. > > I don't see any connection to the rubidium C-field pin so I don't think > there is any adjustment through the main board, just the adjustment thru > the case of the LPRO. > > With some tracing, I can't figure where the 10 MHz output (sma) comes > from. I assume it is functional, but haven't applied power yet. > > The 15 MHz generation looks very similar to the other boad I described > in another message on an FRS-C unit. The active source again seems to > come from an Altera PLD. Maybe it divides 10 MHz by two, and (guess) > narrows the pulse for better 3rd harmonic? Rex Narrowing the pulse width does little for the amplitude of the third harmonic component. There's already plenty with a 50% duty cycle square wave. A waveform with duty duty cycle of 1/6 has the same 3rd hamonic component amplitude as a 50% duty cycle waveform. Narrowing the pulse to a very small duty cycle tends to flatten the the frequency comb whilst reducing the amplitude of all components. see: http://www.wenzel.com/pdffiles/choose.pdf Bruce > Anyway, then it seems to go > through a series resonant LC, with a trimmer on the C. Then thru the 15 > MHz filter, two stages of amplification, and a MCL low-pass filter to > the sma. > > BITE signal from the LPRO goes somewhere so I assume it is at least part > of the alarm connector output. > > If anyone finds or works out the pins on the alarm and interface > connectors, I'd eb interested to hear about it. > > So there we are for now. Quick first look without even trying it yet. > Assuming it works, the LPRO was probably worth my $130 investment. Hope > some of my comments helps someone. > > -Rex > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] Lucent RFG-RB
I just received a Lucent RFG-RB (no -m- in this one) rubidium unit eBay buy from the lady in Atlanta. Thought I'd share a few notes on what it is. Maybe some of this has already been covered -- I lost track of all the emails. Like John, I immediately opened it up, haven't tried it yet, and won't for a while. No GPS, as has been noted in the other messages, that seems to be in the crystal unit. This one was made in 2000. Inside mine, the main component is a Datum LPRO 102500. Seems to be functionally identical to the one in the manual here: http://www.symmetricom.com/media/pdf/manuals/man-lpro.pdf Box front panel: 3 sma's - TP (J1), 10 MHz RF Out (J2), 15 MHz Out (J4) 3 db9's - +24V (P1), Alarm (J3), Interface (J5) 3 led's - Fault, Stby, On Seems the +24V connector only uses two pins: 1 = +24, 2 = return/gnd I assume those two are all that's needed to make it run. Main board is made by Efratom. I don't see any connection to the rubidium C-field pin so I don't think there is any adjustment through the main board, just the adjustment thru the case of the LPRO. With some tracing, I can't figure where the 10 MHz output (sma) comes from. I assume it is functional, but haven't applied power yet. The 15 MHz generation looks very similar to the other boad I described in another message on an FRS-C unit. The active source again seems to come from an Altera PLD. Maybe it divides 10 MHz by two, and (guess) narrows the pulse for better 3rd harmonic? Anyway, then it seems to go through a series resonant LC, with a trimmer on the C. Then thru the 15 MHz filter, two stages of amplification, and a MCL low-pass filter to the sma. BITE signal from the LPRO goes somewhere so I assume it is at least part of the alarm connector output. If anyone finds or works out the pins on the alarm and interface connectors, I'd eb interested to hear about it. So there we are for now. Quick first look without even trying it yet. Assuming it works, the LPRO was probably worth my $130 investment. Hope some of my comments helps someone. -Rex ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
