On Peter Vince's topic, *does anybody in the group know what part of the* *waveforms transmitted by WWV & WWVB mark the second boundaries?*
I was once comparing the timing of PPS pulses from a GPS receiver with WWV's ticks, and saw about 5 msec delay to the ticks (in south central Texas). Obviously propagation and my receiver's internal delays account for most of that, but I never could decide which part of the audio waveform I should be referencing. For WWV, I feel that the best choice would be the central peak in the response of a matched filter designed around the tick waveform, but I bet "they" did something entirely different. Hence the question posed above. Dana On Wed, Aug 15, 2018 at 7:22 AM, Peter Vince <[email protected]> wrote: > I was astonished to see the pulse-width in the document defined from the > base of the (sharp-cornered!) edges, and not the mid-point - totally > impractical! Near the top of the previous page it says: "If required for > testing purposes, the pulse width at the 50% level may be determined by > extrapolation." Now OK, the very wide tolerance on the pulse-width makes > this all rather academic, but surely that spec wasn't written by an > engineer? :-) > > Peter > > On 15 August 2018 at 05:03, Björn <[email protected]> wrote: > > > Hi Bernd, > > > > One reference to 20us 1PPS pulse length is the ICD-GPS-060, see figure > > 3-2, page 3-3 (pdf page 19) > > > > https://www.navcen.uscg.gov/pdf/gps/ICD-GPS-060B.pdf > > > > Group - Are there other standard documents defining duty-cycle, voltage > > levels, rise times etc? > > > > MfG > > > > Björn > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to http://lists.febo.com/mailman/ > listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
