Re: [time-nuts] WWVB d-psk-r down conversion method
Hi Actually stability isn’t the main problem with the progamables. The issue is usually phase noise ad spurs. Often they use odd multi modulo divides rather than a PLL. That gives them a low cost chip, but the output spectrum is pretty poor. Figuring out if you have a “bad one” or not is tough from many data sheets. It’s rare that cheap XO’s come with phase noise and spur plots. Bob On Sep 23, 2014, at 12:04 AM, Hal Murray hmur...@megapathdsl.net wrote: paulsw...@gmail.com said: Did try lots of frequencies and divider math to come up with a simple LO scheme for 61 or 59 KHz. Messy. There are companies that will make a crystal or oscillator at any frequency you want at a not silly price. Delivery is not overnight. Beware: There are several companies selling instant delivery of oscillators running at any frequency you want. They are using a programmable PLL so you won't get the stability you expect from a crystal. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method
Wow. What 8 hours can do for responses. Great comments and appreciated. A piece of the puzzle appears to have gotten lost from the start of the process. This down converter system. Only detects phase change. It is not intended to be a phase locked oscillator system that replicates what the old radios have. Its output flips a signal path to invert or not invert the incoming wwvb signal that feeds the old radios. There is no need for an instantaneous response in the flip circuit. .3-.5 seconds seems fine for the old radios. Want to see if I can get down to .1-.2 sec. Pretty sure from what I have seen so far there is no need to lock the LO nor must it be some precise offset of 100 Hz or anything else. In watching this on a scope with a stable local 100 Hz reference not locked to anything. The phase changes were obvious and useful. One of the comments in the thread was that you could use a good local reference and adjust for the LO drift. I do believe thats the case. I am pretty good at dividing in decades. ;-) But getting ahead of the other criteria. Simple as possible. OK time to fix the HP3335a that failed. Lost my LO for the moment. Regards Paul. WB8TSL On Tue, Sep 23, 2014 at 7:37 AM, Bob Camp kb...@n1k.org wrote: Hi Actually stability isn’t the main problem with the progamables. The issue is usually phase noise ad spurs. Often they use odd multi modulo divides rather than a PLL. That gives them a low cost chip, but the output spectrum is pretty poor. Figuring out if you have a “bad one” or not is tough from many data sheets. It’s rare that cheap XO’s come with phase noise and spur plots. Bob On Sep 23, 2014, at 12:04 AM, Hal Murray hmur...@megapathdsl.net wrote: paulsw...@gmail.com said: Did try lots of frequencies and divider math to come up with a simple LO scheme for 61 or 59 KHz. Messy. There are companies that will make a crystal or oscillator at any frequency you want at a not silly price. Delivery is not overnight. Beware: There are several companies selling instant delivery of oscillators running at any frequency you want. They are using a programmable PLL so you won't get the stability you expect from a crystal. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] WWVB d-psk-r down conversion method...
Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK From: Charles Steinmetz csteinm...@yandex.com Subject: Re: [time-nuts] WWVB d-psk-r down conversion method Paul wrote: The goal is to remove the psk so the old phase tracking receivers can work. Yes, I understand that. But you want them to work like they originally did, with the disciplined oscillator in the phase tracking receiver phase-locked to the WWVB carrier (or else you may as well just ignore WWVB entirely and generate your own 60kHz carrier). Once you add an LO/BFO, the signal you end up with is NOT locked to the WWVB carrier -- it is locked to some frequency that is determined by both WWVB and the LO/BFO (whch means, it is only as accurate and stable as the LO/BFO). So the whole benefit of receiving WWVB in the first place is lost. [In the special case of a TRF receiver, with no LO/BFO, the signal will remain locked to WWVB.] Whats good about this as I just typed to Bob the signal is slow and easy to work on. From what I have seen the phase tracking receivers have a fairly long time constant. So the fact that the phase detect and flip occurs 1/10 of a second later should not have any effect on these radios. It's got nothing to do with how fast or slow the signal you end up with is, or how easy it is to work on. If the frequency and phase of that signal are not uniquely dependent on the WWVB carrier frequency and phase, then the oscillator you discipline will not be disciplined to the precision of WWVB -- it will be disciplined to no better than your own LO/BFO. [Also note that the phase flips at one second intervals no matter what frequency you translate it to -- that is not a unique feature of the 100Hz recovered carrier.] As Alex pointed out, you could in theory use a LO/BFO that is, itself, derived from the disciplined oscillator, and in which the loops will not lock unless the IF and LO have the correct values. But, as Alex also points out, such a scheme will have about the same complexity as a Costas loop. The Tracor itself uses a crude variant of this strategy, in which the LO is guided huff-n-puff style in steps of 1/100 of a cycle, some steps above and some below the correct frequency. But when you are starting with a signal that is already orders of magnitude less stable than a GPS signal, it is just rude to throw away even more stability with that sort of approximation. Furthermore, all of this would need to happen outside of the old-school phase tracking receiver, so you'd end up building your own external phase tracking receiver just to run the old phase tracking receiver. Best regards, Charles Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
The whole point of the d-psk-r is to remove the random phase shifts caused by the new psk modulation scheme and create a signal that the phase locking receivers could use for frequency standard purposes. -Chuck Harris Burt I. Weiner wrote: Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
there is an interesting side effect with that phase modulation: in case the crystal filter is narrow enough --to use for the old AM format-- the phase change creates an additional AM modulation, if you take in consideration that effect by the decoding the modulation, you could recover the time information despite of the presence of the PSK. Question: as fare as I am informed there is no chip/system available to correctly decode the new signal form, what was the purpose of the whole modulation format change? The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? 73 Alex On 9/23/2014 9:16 AM, Burt I. Weiner wrote: Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
OK Goal of teh d-psk-r is to correct the phase shift so any of the radios will work without modification. Be it time or frequency. However for those with just a need for time like the spectracoms, the remodulator circuit does that job very well and has been in use for over 1.5 years. Darn simple. It was updated about march of this year with a discussion on various wwvb atomic clock modules that will work. The d-psk-r will correct the phase issue and allow the Fluke 207 tracor 599, HP 117 etc to work a byproduct of that method is that it allows the time units to also work. I have released some analog d-psk-r approaches and even a direct hack into the spectracom phase receivers. (I hate internal hacks. But if you only had one receiver it makes a lot of sense.) Have shared all of that over time with Time-Nuts. Some folks closer to wwvb then me have used the frequency doubling method. Lucky them all manners of that method fail pretty badly over time on the East Coast. Alex is right as I learned the really narrow Xtals actually loose the signal for numbers of cycles at the phase flip since they are 60 Khz +- a few Hertz. It gaps actually. Burt Make up a remodulator and you are back in business with the 8170. Its great to see those panalplex displays correctly running again. Regards Paul. WB8TSL On Tue, Sep 23, 2014 at 1:11 PM, Alexander Pummer alex...@ieee.org wrote: there is an interesting side effect with that phase modulation: in case the crystal filter is narrow enough --to use for the old AM format-- the phase change creates an additional AM modulation, if you take in consideration that effect by the decoding the modulation, you could recover the time information despite of the presence of the PSK. Question: as fare as I am informed there is no chip/system available to correctly decode the new signal form, what was the purpose of the whole modulation format change? The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? 73 Alex On 9/23/2014 9:16 AM, Burt I. Weiner wrote: Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
it could be that the intention was good , but there is no reliable atomic clock and the company which promised the chip still no t delivered any usable, as I learned from two of my clients which are in the were business of making atomic clocks 73 Alex On 9/23/2014 11:06 AM, Charles Steinmetz wrote: Alex wrote: The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? The changes were made to make today's consumer atomic clocks more robust, not to help any kind of professional receivers (whether time or frequency). Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
Alex wrote: The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? The changes were made to make today's consumer atomic clocks more robust, not to help any kind of professional receivers (whether time or frequency). Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method
Paul wrote: This down converter system. Only detects phase change. * * * Its output flips a signal path to invert or not invert the incoming wwvb signal that feeds the old radios. Ahhh, you are just building a phase detector to trigger an inverter. That's where I hadn't followed you. As you note, the potential drawback of this approach is the length of time it takes to switch the inverter in or out after each phase shift: There is no need for an instantaneous response in the flip circuit. .3-.5 seconds seems fine for the old radios. Want to see if I can get down to .1-.2 sec. Depending on the stability of the disciplined oscillator (inside the old radio), you may need to do better than that. If the old radio uses an OCXO and a very slow discipline loop, 100mS may be good enough. But if it uses a TCXO or a naked crystal and the loop has to be fast enough to help stability in the 1S region, you may need to switch faster to avoid the PLL partially tracking the short burst of anti-phase. Since analog PLLs are hard to make with long time constants (so the loops in the old radios are probably not as slow as you'd like), I suspect you'll see an improvement with faster switching. Of course, you can run the 60kHz carrier through an all-pass filter before the phase switch to delay it if you need to, but you need to watch dispersion vs. temperature if you do that. Pretty sure from what I have seen so far there is no need to lock the LO nor must it be some precise offset of 100 Hz or anything else. For that application, correct. Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
Hi Alex: Sometime in the future there will be chips that will decode the new signals (note the s on the end of that last word). There are a number of frame times the longest one of which takes 17 minutes and is transmitted only once per day. This format offers 23 dB modulation gain compared to the 1 minute time frame transmission that the current clocks use. There are a total of 5 different modulation formats that will be transmitted over different time frames. In the end everyone should have a clock with more frequent updates (on the West coast I might need to wait overnight for a clock to sync after a battery change) and more accuracy. http://prc68.com/I/Loop.shtml#PhaseMod Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Alexander Pummer wrote: there is an interesting side effect with that phase modulation: in case the crystal filter is narrow enough --to use for the old AM format-- the phase change creates an additional AM modulation, if you take in consideration that effect by the decoding the modulation, you could recover the time information despite of the presence of the PSK. Question: as fare as I am informed there is no chip/system available to correctly decode the new signal form, what was the purpose of the whole modulation format change? The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? 73 Alex On 9/23/2014 9:16 AM, Burt I. Weiner wrote: Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
Hi Brooke, I hope that you are right with that chip, and despite the name change of the company -- now Xtendwave -- and recovering they will deliver something some times. I can see that with correlation and averaging schemes the signal to noise ratio of data, perhaps constant frequency could be improved, but I would be very interested to see of the mathematical model of improving the signal to noise ratio of timing. Regards Alex On 9/23/2014 1:08 PM, Brooke Clarke wrote: Hi Alex: Sometime in the future there will be chips that will decode the new signals (note the s on the end of that last word). There are a number of frame times the longest one of which takes 17 minutes and is transmitted only once per day. This format offers 23 dB modulation gain compared to the 1 minute time frame transmission that the current clocks use. There are a total of 5 different modulation formats that will be transmitted over different time frames. In the end everyone should have a clock with more frequent updates (on the West coast I might need to wait overnight for a clock to sync after a battery change) and more accuracy. http://prc68.com/I/Loop.shtml#PhaseMod Have Fun, ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
Hi Alex: There's not a requirement that Xtgendwave make the chip. The modulation format is published by NIST and anyone can make a receiver. I would hope there's some Time Nuts that would be interested in doing this rather than trying to remove the phase modulation. It's my understanding that by using the fast (100 bits/second - 10 second frame time) signal you can get more precision than possible using the old WWVB signal. Note: The Xtgendwave patents spend a lot of time and effort compensating for the poor quality of the watch crystal. If it's in spec but not exactly on frequency, then decoding a signal that's 17 minutes long is a big problem. For time nuts use where we have a precision LO all that goes away and instead we could be looking at how to get more precision and at the same time more updates. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Alexander Pummer wrote: Hi Brooke, I hope that you are right with that chip, and despite the name change of the company -- now Xtendwave -- and recovering they will deliver something some times. I can see that with correlation and averaging schemes the signal to noise ratio of data, perhaps constant frequency could be improved, but I would be very interested to see of the mathematical model of improving the signal to noise ratio of timing. Regards Alex On 9/23/2014 1:08 PM, Brooke Clarke wrote: Hi Alex: Sometime in the future there will be chips that will decode the new signals (note the s on the end of that last word). There are a number of frame times the longest one of which takes 17 minutes and is transmitted only once per day. This format offers 23 dB modulation gain compared to the 1 minute time frame transmission that the current clocks use. There are a total of 5 different modulation formats that will be transmitted over different time frames. In the end everyone should have a clock with more frequent updates (on the West coast I might need to wait overnight for a clock to sync after a battery change) and more accuracy. http://prc68.com/I/Loop.shtml#PhaseMod Have Fun, ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
OK this is shifting to an Xtendwave discussion and the magical chips. Been trying to get some for a long time. They had some bare dies earlier this year. But thats a bit small for me to work on. I don't really have any intent to use the Xtendwave chip for this project. Maybe one day. I can see how it could be useful. Just this project has taken on a life of its own and I want to wrap it up and get my old radios running again. Silly as that may be considering good ole GPS and the Jackson Labs GPDSOs. Regards Paul WB8TSL On Tue, Sep 23, 2014 at 5:55 PM, Alexander Pummer alex...@ieee.org wrote: Hi Brooke, I hope that you are right with that chip, and despite the name change of the company -- now Xtendwave -- and recovering they will deliver something some times. I can see that with correlation and averaging schemes the signal to noise ratio of data, perhaps constant frequency could be improved, but I would be very interested to see of the mathematical model of improving the signal to noise ratio of timing. Regards Alex On 9/23/2014 1:08 PM, Brooke Clarke wrote: Hi Alex: Sometime in the future there will be chips that will decode the new signals (note the s on the end of that last word). There are a number of frame times the longest one of which takes 17 minutes and is transmitted only once per day. This format offers 23 dB modulation gain compared to the 1 minute time frame transmission that the current clocks use. There are a total of 5 different modulation formats that will be transmitted over different time frames. In the end everyone should have a clock with more frequent updates (on the West coast I might need to wait overnight for a clock to sync after a battery change) and more accuracy. http://prc68.com/I/Loop.shtml#PhaseMod Have Fun, ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
According to the NIST documentation there were a couple of motivations... 1. BPSK is easier to receive in high noise environments so they say. 2. The new format supports sending additional information in addition to the time of day. The other messages are interleaved into each minute and they take a long time to receive. Mike Harpe On Tue, Sep 23, 2014 at 1:11 PM, Alexander Pummer alex...@ieee.org wrote: there is an interesting side effect with that phase modulation: in case the crystal filter is narrow enough --to use for the old AM format-- the phase change creates an additional AM modulation, if you take in consideration that effect by the decoding the modulation, you could recover the time information despite of the presence of the PSK. Question: as fare as I am informed there is no chip/system available to correctly decode the new signal form, what was the purpose of the whole modulation format change? The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? 73 Alex On 9/23/2014 9:16 AM, Burt I. Weiner wrote: Charles, If I recall correctly, the original point of the d-psk-r was to cause the clocks to again read the correct time, not maintain their use as a frequency standard. I have a Symmetricom 8170 that I used to use only as a clock to tell the time of day. Since WWVB's addition of the PSK coding, it's only good to watch the pretty blinken lights. Burt, K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] LTE-Lite Eval Kit available
Hello Time-Nuts, we put together an email list with the large number of email info-requests I got for the LTE-Lite eval kits over the weekend. I have just sent an email to everyone on that email list from my corporate email account. Unfortunately my AOL account has a tendency to eat emails, so if you did not receive the info email from me today and should be on that list then please drop me a line directly and I will add you to the list immediately. I apologize in advance in case I did not properly capture your email, thanks, Said ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method
Hi If the idea is to decode in software in order to “de-psk” with a switch, then things are indeed easier. My *guess* is that the loops in most WWVB systems are tolerant of noise bursts already. If not, they would have a hard time with the normal RX environment. There are a number of ways to build a PLL and make that happen, even with long time constants involved. They probably used one or more of the common approaches. So here’s a plan: 10 MHz / 168 = 59.532 KHz 168 is 8 x 7 x 3. That’s two 4 bit programable divider chips and a divide by 8. With 10 MHz in, it does not have to be very fast. There are (cheap) CPU chips that will do it on a PWM output. If it’s DIP packages, one 74AC161’s should do the job for the programable sections. You would need a NAND gate for each of the programable sections as well. The divide by two’s can be done several ways. I’d put one at the tail end and the other two at the front end. The 467 Hz note is slow enough to be pretty easy to process with a simple CPU. Bob On Sep 23, 2014, at 11:54 AM, paul swed paulsw...@gmail.com wrote: Wow. What 8 hours can do for responses. Great comments and appreciated. A piece of the puzzle appears to have gotten lost from the start of the process. This down converter system. Only detects phase change. It is not intended to be a phase locked oscillator system that replicates what the old radios have. Its output flips a signal path to invert or not invert the incoming wwvb signal that feeds the old radios. There is no need for an instantaneous response in the flip circuit. .3-.5 seconds seems fine for the old radios. Want to see if I can get down to .1-.2 sec. Pretty sure from what I have seen so far there is no need to lock the LO nor must it be some precise offset of 100 Hz or anything else. In watching this on a scope with a stable local 100 Hz reference not locked to anything. The phase changes were obvious and useful. One of the comments in the thread was that you could use a good local reference and adjust for the LO drift. I do believe thats the case. I am pretty good at dividing in decades. ;-) But getting ahead of the other criteria. Simple as possible. OK time to fix the HP3335a that failed. Lost my LO for the moment. Regards Paul. WB8TSL On Tue, Sep 23, 2014 at 7:37 AM, Bob Camp kb...@n1k.org wrote: Hi Actually stability isn’t the main problem with the progamables. The issue is usually phase noise ad spurs. Often they use odd multi modulo divides rather than a PLL. That gives them a low cost chip, but the output spectrum is pretty poor. Figuring out if you have a “bad one” or not is tough from many data sheets. It’s rare that cheap XO’s come with phase noise and spur plots. Bob On Sep 23, 2014, at 12:04 AM, Hal Murray hmur...@megapathdsl.net wrote: paulsw...@gmail.com said: Did try lots of frequencies and divider math to come up with a simple LO scheme for 61 or 59 KHz. Messy. There are companies that will make a crystal or oscillator at any frequency you want at a not silly price. Delivery is not overnight. Beware: There are several companies selling instant delivery of oscillators running at any frequency you want. They are using a programmable PLL so you won't get the stability you expect from a crystal. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] LTE-Lite Eval Kit available
Hello. Please add me to the list of people interested in the LTE-Lite eval kits. (I did not send a previous email, and you did not lose it - I've just been slow in writing). Thanks, Dave On Tue, Sep 23, 2014 at 8:05 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Hello Time-Nuts, we put together an email list with the large number of email info-requests I got for the LTE-Lite eval kits over the weekend. I have just sent an email to everyone on that email list from my corporate email account. Unfortunately my AOL account has a tendency to eat emails, so if you did not receive the info email from me today and should be on that list then please drop me a line directly and I will add you to the list immediately. I apologize in advance in case I did not properly capture your email, thanks, Said ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] LTE-Lite Eval Kit available
Said, Please also add me to the list of interested parties for the LTE-lite eval kit. thanks -eric On Tue, Sep 23, 2014 at 5:05 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Hello Time-Nuts, we put together an email list with the large number of email info-requests I got for the LTE-Lite eval kits over the weekend. I have just sent an email to everyone on that email list from my corporate email account. Unfortunately my AOL account has a tendency to eat emails, so if you did not receive the info email from me today and should be on that list then please drop me a line directly and I will add you to the list immediately. I apologize in advance in case I did not properly capture your email, thanks, Said ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- --Eric _ Eric Garner ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] WWVB d-psk-r down conversion method...
On 9/23/14, 10:11 AM, Alexander Pummer wrote: there is an interesting side effect with that phase modulation: in case the crystal filter is narrow enough --to use for the old AM format-- the phase change creates an additional AM modulation, if you take in consideration that effect by the decoding the modulation, you could recover the time information despite of the presence of the PSK. Question: as fare as I am informed there is no chip/system available to correctly decode the new signal form, what was the purpose of the whole modulation format change? The old AM format was happy with cca 200Hz bandwidth to recover the time information, which was utilized in many professional receivers, which used a crystal filter for 60kHz, for the PSK format the required bandwidth is at least five times wider, so crystal filter would be problematic and much more costly, the higher required bandwidth brings also more noise actually where is the advantage of the new modulation scheme? These days I suspect nobody would use a crystal filter. You'd digitize at some useful rate and implement your filter in software. The real question would be how many bits do you need in the ADC and how fast do you run it. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
