Re: [time-nuts] Cutler NAA on 24.0kHz....
interesting to read: a very low frequency comparator for relating local frequency to u.s. standards http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1964-10.pdf 73 alex On 8/15/2014 4:52 PM, Arthur Dent wrote: "Not sure whats up with the link when I click it I get the download. Its a 2.5MB file http://www.glkinst.com/test-equipment/manuals/Tracor900A.pdf. " The problem with the above link is the period is included as part of the link when you click on it. It will work without the period. -Arthur ___ 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] Cutler NAA on 24.0kHz....
On 15 Aug 2014 at 20:57, paul swed wrote: > Did check NAA and its banging into Boston. 2 Megawatts to that antenna should show VOLTS at your place. We used that station for many years for VLF propagation research in Missoula, Montana. It banged in 24/7/365. Still does, except when its down for maintenance. So did Jim Creek (of course) and NWC in Australia, and a station whose call I have forgotten in the Canal Zone. Back in 1973. Ken W7EKB ___ 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] TM 500 extender board en HP 5370 extender boards
Hello ! Please count me in also for two sets of TM 500 extenders and one HP 5370 board set. Please contact me off list at : va2hdd (at) amsat.org when you can, no rush, I have one question about this project. Thank you, Claude Houde VA2 HDD Le 2014-08-15 12:00, time-nuts-requ...@febo.com a écrit : Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than "Re: Contents of time-nuts digest..." Today's Topics: 1. Re: HP5370 extender cards? (paul swed) 2. HP5370 extender cards? (Mark Sims) -- Message: 1 Date: Thu, 14 Aug 2014 19:47:05 -0400 From: paul swed To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP5370 extender cards? Message-ID: Content-Type: text/plain; charset=UTF-8 Let me know when things settle. Most likely will want a set. Regards Paul WB8TSL On Thu, Aug 14, 2014 at 12:12 PM, Mark Sims wrote: It usually takes 2-3 weeks to get boards back once sent to the fab (in China). Supposedly the boards that I am having them do for another project should be here today and I can verify their quality. I also laid out a 20 pin extender to connect the input board to the front panel, but I don't think those would be too useful. You can extend the other side of the input board/front panel using a 36 pin extender. A while back I had the idea of doing a replacement board for the custom HP input comparator chips that fry is you overload the 5370 inputs. Need to start looking at what that would take... there are two different versions of that chip/input board. The replacement could be for just the chip or the complete input board. -- Approx how long should they be ready to ship after you decide to proceed with the order? ___ 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. -- Message: 2 Date: Fri, 15 Aug 2014 01:06:25 + From: Mark Sims To: "time-nuts@febo.com" Subject: [time-nuts] HP5370 extender cards? Message-ID: Content-Type: text/plain; charset="iso-8859-1" Yes, can ship world wide. Not sure what the postage will be, but should not be too bad. I'm leaning towards a 3 card set as the standard. Two of the 36 pin extenders and one of the 44 pin. There are a couple of other misc boards in the machine with different pin counts (oscillator, oscillator power, oscillator buffer) but those three should be able to handle most of the work. If you really needed to extend the 30 pin oscillator or buffer cards, you could hack up a 36 pin card. I got my other projects' boards in from China today. They look good. Now to get the TM500 and 5370 boards on order. -- ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts End of time-nuts Digest, Vol 121, Issue 40 ** ___ 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] Cutler NAA on 24.0kHz....
Did check NAA and its banging into Boston. Had to put 40 db anttenuator inline to make it reasonable. Using the wwvb antenna. Most likely would do just fine with 6 ft of wire. Ok only had 4 ft of wire and its there. Could really use 10-12ft. :-) So maybe my fillings won't pick it up. Regards Paul. WB8TSL On Fri, Aug 15, 2014 at 7:51 PM, paul swed wrote: > Oh Ebay has one for sale for the person that just needs one. Todays buy > now $1693 plus shipping. > There you go a deal a day. I think not. > regards > Paul > WB8TSL > > > On Fri, Aug 15, 2014 at 7:48 PM, paul swed wrote: > >> Whats interesting is I had never heard of the 900 till I started looking >> at NAA and msk. >> Regards >> Paul. >> >> >> On Fri, Aug 15, 2014 at 6:43 PM, David I. Emery >> wrote: >> >>> On Fri, Aug 15, 2014 at 03:39:07PM -0700, Pete Lancashire wrote: >>> > URL ok from here >>> >>> The text of the original post had "*"s in the URL... which >>> didn't work so well... >>> >>> Partly pilot error here... >>> >>> Works OK without the "*"s >>> >>> >>> >>> > >>> > -pete >>> >>> >>> -- >>> Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, >>> Mass 02493 >>> "An empty zombie mind with a forlorn barely readable weatherbeaten >>> 'For Rent' sign still vainly flapping outside on the weed encrusted pole >>> - in >>> celebration of what could have been, but wasn't and is not to be now >>> either." >>> >>> ___ >>> 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] Cutler NAA on 24.0kHz....
so much for copy and paste. Thanks On Fri, Aug 15, 2014 at 7:52 PM, Arthur Dent wrote: > "Not sure whats up with the link when I click it I get the download. Its a > 2.5MB file > http://www.glkinst.com/test-equipment/manuals/Tracor900A.pdf. " > > The problem with the above link is the period is included as part of the > link when you click on it. It will work without the period. > > -Arthur > ___ > 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] Cutler NAA on 24.0kHz....
"Not sure whats up with the link when I click it I get the download. Its a 2.5MB file http://www.glkinst.com/test-equipment/manuals/Tracor900A.pdf. " The problem with the above link is the period is included as part of the link when you click on it. It will work without the period. -Arthur ___ 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] Cutler NAA on 24.0kHz....
Oh Ebay has one for sale for the person that just needs one. Todays buy now $1693 plus shipping. There you go a deal a day. I think not. regards Paul WB8TSL On Fri, Aug 15, 2014 at 7:48 PM, paul swed wrote: > Whats interesting is I had never heard of the 900 till I started looking > at NAA and msk. > Regards > Paul. > > > On Fri, Aug 15, 2014 at 6:43 PM, David I. Emery > wrote: > >> On Fri, Aug 15, 2014 at 03:39:07PM -0700, Pete Lancashire wrote: >> > URL ok from here >> >> The text of the original post had "*"s in the URL... which >> didn't work so well... >> >> Partly pilot error here... >> >> Works OK without the "*"s >> >> >> >> > >> > -pete >> >> >> -- >> Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, >> Mass 02493 >> "An empty zombie mind with a forlorn barely readable weatherbeaten >> 'For Rent' sign still vainly flapping outside on the weed encrusted pole >> - in >> celebration of what could have been, but wasn't and is not to be now >> either." >> >> ___ >> 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] Cutler NAA on 24.0kHz....
Whats interesting is I had never heard of the 900 till I started looking at NAA and msk. Regards Paul. On Fri, Aug 15, 2014 at 6:43 PM, David I. Emery wrote: > On Fri, Aug 15, 2014 at 03:39:07PM -0700, Pete Lancashire wrote: > > URL ok from here > > The text of the original post had "*"s in the URL... which > didn't work so well... > > Partly pilot error here... > > Works OK without the "*"s > > > > > > > -pete > > > -- > Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, > Mass 02493 > "An empty zombie mind with a forlorn barely readable weatherbeaten > 'For Rent' sign still vainly flapping outside on the weed encrusted pole - > in > celebration of what could have been, but wasn't and is not to be now > either." > > ___ > 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] Cutler NAA on 24.0kHz....
On Fri, Aug 15, 2014 at 03:39:07PM -0700, Pete Lancashire wrote: > URL ok from here The text of the original post had "*"s in the URL... which didn't work so well... Partly pilot error here... Works OK without the "*"s > > -pete -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] Cutler NAA on 24.0kHz....
URL ok from here -pete On Fri, Aug 15, 2014 at 3:25 PM, paul swed wrote: > Not sure whats up with the link when I click it I get the download. Its a > 2.5MB file > http://www.glkinst.com/test-equipment/manuals/Tracor900A.pdf. > Try his main page http://www.glkinst.com > I did see the info there also. > Browsers we luv'em. > Regards > Paul. > WB8TSL > > > On Fri, Aug 15, 2014 at 6:20 PM, David I. Emery > wrote: > > > On Fri, Aug 15, 2014 at 04:56:01PM -0400, paul swed wrote: > > > Yes I can see on page 2 of the pdf thats the trick. Its a non costas > loop > > > trick. > > > > That PDF is returning a 404 for me at the moment... > > > > > > > > -- > > Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, > > Mass 02493 > > "An empty zombie mind with a forlorn barely readable weatherbeaten > > 'For Rent' sign still vainly flapping outside on the weed encrusted pole > - > > in > > celebration of what could have been, but wasn't and is not to be now > > either." > > > > ___ > > 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] Cutler NAA on 24.0kHz....
Not sure whats up with the link when I click it I get the download. Its a 2.5MB file http://www.glkinst.com/test-equipment/manuals/Tracor900A.pdf. Try his main page http://www.glkinst.com I did see the info there also. Browsers we luv'em. Regards Paul. WB8TSL On Fri, Aug 15, 2014 at 6:20 PM, David I. Emery wrote: > On Fri, Aug 15, 2014 at 04:56:01PM -0400, paul swed wrote: > > Yes I can see on page 2 of the pdf thats the trick. Its a non costas loop > > trick. > > That PDF is returning a 404 for me at the moment... > > > > -- > Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, > Mass 02493 > "An empty zombie mind with a forlorn barely readable weatherbeaten > 'For Rent' sign still vainly flapping outside on the weed encrusted pole - > in > celebration of what could have been, but wasn't and is not to be now > either." > > ___ > 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] Cutler NAA on 24.0kHz....
On Fri, Aug 15, 2014 at 04:56:01PM -0400, paul swed wrote: > Yes I can see on page 2 of the pdf thats the trick. Its a non costas loop > trick. That PDF is returning a 404 for me at the moment... -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] Cutler NAA on 24.0kHz....
On Fri, Aug 15, 2014 at 04:56:01PM -0400, paul swed wrote: > Yes I can see on page 2 of the pdf thats the trick. Its a non costas loop > trick. > "The action of the MSK card doubles the phase shift". > So it is the classic double the frequency stateless carrier recovery. that > may drop phase due to noise. Needless to say one can track the recovered carrier with a very narrow loop which will not slip in phase easily during a fade. I believe you found that simply using it to clock a flip flop wasn't reliable... but a narrow carrier tracking loop tracking it would be... -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] Cutler NAA on 24.0kHz....
Yes I can see on page 2 of the pdf thats the trick. Its a non costas loop trick. "The action of the MSK card doubles the phase shift". So it is the classic double the frequency stateless carrier recovery. that may drop phase due to noise. Regards Paul WB8TSL On Fri, Aug 15, 2014 at 4:52 PM, paul swed wrote: > www.glkinst.com/test-equipment/manuals/Tracor*900A*.pdf > > > On Fri, Aug 15, 2014 at 4:49 PM, paul swed wrote: > >> David >> Yes I have seen various comments and documents describing MSK that way. >> But have to say the tracor 900 does not use that method to establish a >> reference. >> Its a few opamps perhaps one side acting as a phase delay summing with >> the original and hitting a BPF. all of that running at 100Hz center >> frequency. >> Through this magic the 900 could use NAA as a phase tracking reference. >> Its as if its a classic phase doubler. The documentation almost speaks to >> that. >> Its seriously simple. >> Regards >> Paul. >> WB8TSL >> >> >> >> On Fri, Aug 15, 2014 at 4:31 PM, David I. Emery >> wrote: >> >>> On Fri, Aug 15, 2014 at 03:09:23PM -0400, paul swed wrote: >>> >>> > I had discounted it because of the lack of info and totally unclear >>> how to >>> > get rid of the FSK. MSK is FSK just with a very narrow shift. Also the >>> > effects of the fsk on the carrier. Hmmm glad I am typing this. >>> > It may be that the mark or the space is indeed exactly the true >>> carrier and >>> > that op amp circuit is notching out the shifted carrier. I will bet >>> thats >>> > the trick! >>> >>> >>> MSK is a kind of continuous phase differentially coded PSK in >>> which the carrier phase smoothly shifts either EXACTLY plus 90 degrees >>> or EXACTLY minus 90 degrees in EXACTLY one symbol time - in the MSK >>> variety of PSK the transmitted carrier phase never stays the same as the >>> it was the last symbol time. When transmitting steady mark there are a >>> series of these shifts plus 90 degrees (hi frequency mark) one after the >>> other, and when transmitting steady space there is a series of minus 90 >>> degree shifts. >>> >>> Obviously a steady negative phase shift is what is produced by >>> a signal below a center "carrier" frequency and a steady positive >>> phase shift by one above that frequency. Thus the isomorphism with >>> filtered FSK. >>> >>> Effectively a QPSK (multi-arm Costas type) tracking loop should >>> be able to track a MSK signal just as if it was a filtered QPSK signal >>> with only 90 degree and minus 90 phase shifts each symbol time and >>> generate >>> a phase continuous recovered carrier. >>> >>> >>> >>> >>> >>> -- >>> Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, >>> Mass 02493 >>> "An empty zombie mind with a forlorn barely readable weatherbeaten >>> 'For Rent' sign still vainly flapping outside on the weed encrusted pole >>> - in >>> celebration of what could have been, but wasn't and is not to be now >>> either." >>> >>> ___ >>> 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] Cutler NAA on 24.0kHz....
David Yes I have seen various comments and documents describing MSK that way. But have to say the tracor 900 does not use that method to establish a reference. Its a few opamps perhaps one side acting as a phase delay summing with the original and hitting a BPF. all of that running at 100Hz center frequency. Through this magic the 900 could use NAA as a phase tracking reference. Its as if its a classic phase doubler. The documentation almost speaks to that. Its seriously simple. Regards Paul. WB8TSL On Fri, Aug 15, 2014 at 4:31 PM, David I. Emery wrote: > On Fri, Aug 15, 2014 at 03:09:23PM -0400, paul swed wrote: > > > I had discounted it because of the lack of info and totally unclear how > to > > get rid of the FSK. MSK is FSK just with a very narrow shift. Also the > > effects of the fsk on the carrier. Hmmm glad I am typing this. > > It may be that the mark or the space is indeed exactly the true carrier > and > > that op amp circuit is notching out the shifted carrier. I will bet thats > > the trick! > > > MSK is a kind of continuous phase differentially coded PSK in > which the carrier phase smoothly shifts either EXACTLY plus 90 degrees > or EXACTLY minus 90 degrees in EXACTLY one symbol time - in the MSK > variety of PSK the transmitted carrier phase never stays the same as the > it was the last symbol time. When transmitting steady mark there are a > series of these shifts plus 90 degrees (hi frequency mark) one after the > other, and when transmitting steady space there is a series of minus 90 > degree shifts. > > Obviously a steady negative phase shift is what is produced by > a signal below a center "carrier" frequency and a steady positive > phase shift by one above that frequency. Thus the isomorphism with > filtered FSK. > > Effectively a QPSK (multi-arm Costas type) tracking loop should > be able to track a MSK signal just as if it was a filtered QPSK signal > with only 90 degree and minus 90 phase shifts each symbol time and generate > a phase continuous recovered carrier. > > > > > > -- > Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, > Mass 02493 > "An empty zombie mind with a forlorn barely readable weatherbeaten > 'For Rent' sign still vainly flapping outside on the weed encrusted pole - > in > celebration of what could have been, but wasn't and is not to be now > either." > > ___ > 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] Cutler NAA on 24.0kHz....
www.glkinst.com/test-equipment/manuals/Tracor*900A*.pdf On Fri, Aug 15, 2014 at 4:49 PM, paul swed wrote: > David > Yes I have seen various comments and documents describing MSK that way. > But have to say the tracor 900 does not use that method to establish a > reference. > Its a few opamps perhaps one side acting as a phase delay summing with the > original and hitting a BPF. all of that running at 100Hz center frequency. > Through this magic the 900 could use NAA as a phase tracking reference. > Its as if its a classic phase doubler. The documentation almost speaks to > that. > Its seriously simple. > Regards > Paul. > WB8TSL > > > > On Fri, Aug 15, 2014 at 4:31 PM, David I. Emery > wrote: > >> On Fri, Aug 15, 2014 at 03:09:23PM -0400, paul swed wrote: >> >> > I had discounted it because of the lack of info and totally unclear how >> to >> > get rid of the FSK. MSK is FSK just with a very narrow shift. Also the >> > effects of the fsk on the carrier. Hmmm glad I am typing this. >> > It may be that the mark or the space is indeed exactly the true carrier >> and >> > that op amp circuit is notching out the shifted carrier. I will bet >> thats >> > the trick! >> >> >> MSK is a kind of continuous phase differentially coded PSK in >> which the carrier phase smoothly shifts either EXACTLY plus 90 degrees >> or EXACTLY minus 90 degrees in EXACTLY one symbol time - in the MSK >> variety of PSK the transmitted carrier phase never stays the same as the >> it was the last symbol time. When transmitting steady mark there are a >> series of these shifts plus 90 degrees (hi frequency mark) one after the >> other, and when transmitting steady space there is a series of minus 90 >> degree shifts. >> >> Obviously a steady negative phase shift is what is produced by >> a signal below a center "carrier" frequency and a steady positive >> phase shift by one above that frequency. Thus the isomorphism with >> filtered FSK. >> >> Effectively a QPSK (multi-arm Costas type) tracking loop should >> be able to track a MSK signal just as if it was a filtered QPSK signal >> with only 90 degree and minus 90 phase shifts each symbol time and >> generate >> a phase continuous recovered carrier. >> >> >> >> >> >> -- >> Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, >> Mass 02493 >> "An empty zombie mind with a forlorn barely readable weatherbeaten >> 'For Rent' sign still vainly flapping outside on the weed encrusted pole >> - in >> celebration of what could have been, but wasn't and is not to be now >> either." >> >> ___ >> 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] Cutler NAA on 24.0kHz....
On Fri, Aug 15, 2014 at 03:09:23PM -0400, paul swed wrote: > I had discounted it because of the lack of info and totally unclear how to > get rid of the FSK. MSK is FSK just with a very narrow shift. Also the > effects of the fsk on the carrier. Hmmm glad I am typing this. > It may be that the mark or the space is indeed exactly the true carrier and > that op amp circuit is notching out the shifted carrier. I will bet thats > the trick! MSK is a kind of continuous phase differentially coded PSK in which the carrier phase smoothly shifts either EXACTLY plus 90 degrees or EXACTLY minus 90 degrees in EXACTLY one symbol time - in the MSK variety of PSK the transmitted carrier phase never stays the same as the it was the last symbol time. When transmitting steady mark there are a series of these shifts plus 90 degrees (hi frequency mark) one after the other, and when transmitting steady space there is a series of minus 90 degree shifts. Obviously a steady negative phase shift is what is produced by a signal below a center "carrier" frequency and a steady positive phase shift by one above that frequency. Thus the isomorphism with filtered FSK. Effectively a QPSK (multi-arm Costas type) tracking loop should be able to track a MSK signal just as if it was a filtered QPSK signal with only 90 degree and minus 90 phase shifts each symbol time and generate a phase continuous recovered carrier. -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] Cutler NAA on 24.0kHz....
NAA actually is above and below 24KHz. That said I suspect that the system simply averages the MSK out of the loop by the filter TC of the PLL. There are numbers of propagation papers on NAA. Paul WB8TSL On Fri, Aug 15, 2014 at 3:09 PM, paul swed wrote: > Indeed according to the tracor 900 manual you could get to -11th in 24 > hours best case. Further comment was NAA is CS as of 1976! The 900 indeed > has a semi simple op amp adapter thing that reduces or gets rid of the MSK. > Though I have read the description and details it makes no sense as to how > it gets rid of the shift. (Quite curious magic) > The manuals quite a good read at 52 pages a lot of detail. Further all of > the unit could be built again its all simple technology or concepts adapted > to more modern methods. > > The only gotcha as time nuts goes is it ain't NIST. Nor is there time and > I don't care about time I simply want an alternate frequency reference. > Here at Boston I can hear it in my fillings. :-) I could also hear LORAN > C. My type of pipe. > By the way Paul/Ziggy was also after me on NAA to consider it. > > I had discounted it because of the lack of info and totally unclear how to > get rid of the FSK. MSK is FSK just with a very narrow shift. Also the > effects of the fsk on the carrier. Hmmm glad I am typing this. > It may be that the mark or the space is indeed exactly the true carrier > and that op amp circuit is notching out the shifted carrier. I will bet > thats the trick! > > Regards > Paul > WB8TSL > > > > On Tue, Aug 12, 2014 at 10:25 PM, Brian, WA1ZMS wrote: > >> So does anyone know what frequency stability NAA has as of today? >> >> >> >> When I fire-up my VLF RX converter they are so loud I'd hate to live near >> the site. >> >> One might be able to hear it with silver fillings in their teeth while >> eating a lemon! ;- ) >> >> >> >> >> >> -Brian, WA1ZMS >> >> >> >> ___ >> 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] Cutler NAA on 24.0kHz....
Indeed according to the tracor 900 manual you could get to -11th in 24 hours best case. Further comment was NAA is CS as of 1976! The 900 indeed has a semi simple op amp adapter thing that reduces or gets rid of the MSK. Though I have read the description and details it makes no sense as to how it gets rid of the shift. (Quite curious magic) The manuals quite a good read at 52 pages a lot of detail. Further all of the unit could be built again its all simple technology or concepts adapted to more modern methods. The only gotcha as time nuts goes is it ain't NIST. Nor is there time and I don't care about time I simply want an alternate frequency reference. Here at Boston I can hear it in my fillings. :-) I could also hear LORAN C. My type of pipe. By the way Paul/Ziggy was also after me on NAA to consider it. I had discounted it because of the lack of info and totally unclear how to get rid of the FSK. MSK is FSK just with a very narrow shift. Also the effects of the fsk on the carrier. Hmmm glad I am typing this. It may be that the mark or the space is indeed exactly the true carrier and that op amp circuit is notching out the shifted carrier. I will bet thats the trick! Regards Paul WB8TSL On Tue, Aug 12, 2014 at 10:25 PM, Brian, WA1ZMS wrote: > So does anyone know what frequency stability NAA has as of today? > > > > When I fire-up my VLF RX converter they are so loud I'd hate to live near > the site. > > One might be able to hear it with silver fillings in their teeth while > eating a lemon! ;- ) > > > > > > -Brian, WA1ZMS > > > > ___ > 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.