I was using a HP 105B and 117A before the Austron 2100F and still have them. From what I remember, the diurnal shift was not repeatable.
By looking at an output from the 117A and syncing the 'scope to the 105B, I could assess the quality of the signal pretty well. Sometimes it was stable, sometimes it was jittering all over the place by a cycle or more. Bottom line is, IMO, WWVB is no substitute for LORAN. I'm still hoping that the european chains will be usable. YMMV, -John ================ > Hi > > Yes indeed, you need to be sure you don't get a cycle slip. That's not > trivial when the signal goes to zero while moving phase. > > There I think you need to depend on something like a reasonable OCXO and a > long time constant loop. That brings in other problems. I assume that you > are going to have to train your loop to "expect" the ID shifts and time > markers. Again, they are predictable. It's just software .... > > More or less: > > Take all of the things you can compute about the signal and feed them in. > Lock the "computed" signal against the received signal. Way less complex > than what they do with GPS. Since it's all *very* slow, a beater PC can > easily keep up with all the adjustment math. > > Bob > > > On Feb 8, 2010, at 8:28 PM, J. Forster wrote: > >> If you track for a day, and draw a straight line throught the diurnal >> shift, you can easily see a frequency drift of 45 degrees. That's 1/8 >> cycle of 60 KHz or about 2 uS. So 2x 10 E-6 out of 10 E5, so you can see >> 2 >> x 10 E-11 in a day. >> >> ASSUMING the lock does not break. >> >> -John >> >> =================== >> >> >> >>> Hi >>> >>> People rarely want to use WWVB mobile. The location of the transmitter >>> and >>> receiver can be looked up on a map. The time of sunrise at both >>> locations >>> should be something that could be calculated. >>> >>> Assuming you are willing to put up with all of that, you should be able >>> to >>> do a first order correction on the shifts. The question obviously is - >>> just how good would the net result be? Is it a 5:1 sort of thing or do >>> you >>> get a couple of orders of magnitude? >>> >>> Bob >>> >>> On Feb 8, 2010, at 6:40 PM, J. Forster wrote: >>> >>>> Yes, but WWVB is a PITA to use (because of the diurnal shifts) >>>> compared >>>> to >>>> LORAN. >>>> >>>> -John >>>> >>>> =============== >>>> >>>> >>>>> Hi >>>>> >>>>> WWVB is pretty safe. When they do a cost/benefit thing on these >>>>> services, >>>>> they take a look at how many taxpayers are using the service as >>>>> intended. >>>>> The "mission" of WWWVB is to put out time signals. There are a *lot* >>>>> of >>>>> taxpayers with WWVB "atomic clocks" on their walls. >>>>> >>>>> Bob >>>>> >>>>> -----Original Message----- >>>>> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] >>>>> On >>>>> Behalf Of Don Henderickx >>>>> Sent: Monday, February 08, 2010 4:07 PM >>>>> To: Discussion of precise time and frequency measurement >>>>> Subject: [time-nuts] True to there word. >>>>> >>>>> The lights went out (actually red) on my Austron 2100 r this morning. >>>>> (whats next WWVB ?) >>>>> Don H >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > 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.