In message <[email protected]>, "R ichard H McCorkle" writes:
>See the chart TVB produced to see the PRS10 hump in published data. >http://www.leapsecond.com/museum/prs10/ I have measured similar data when the PRS10 is fed a 1PPS from a GPS without sawtooth correction. The PRS10 has a 1/256 exponential average filter which can get rid of most of that noise, and I suspect Tom didn't enable it for that measurement. But even with that filter, the "hanging bridges" leak through at all relevant timeconstants of the PRS10's internal PLL. I tried converting the "negative saw-tooth" and injecting it into the PRS10 via the serial port, but the results were at best very mixed. In the end I used the PRS10 to timestamp the 1PPS, pulled the measurement out via the serial port, and implemented my own neg-saw corrected PLL in software, which injected the correction back into the PRS10 via the serial port. When you do that, you get much better results, at 2Hz and elsewhere. -- 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 -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
