More... You might try logging the output of an audio oscillator, Even an HP 20 would work.
-John ================= > I agree: I don't think this is possible on a power line. Better to use a > second sampling unit to check. > > On Sat, Sep 1, 2012 at 3:30 PM, J. Forster <j...@quikus.com> wrote: > >> IMO, you have an instrumentation issue. I don't think the power grid can >> do anything like that. >> >> YMMV, >> >> -John >> >> =============== >> >> >> >> > The context is using the 60 Hz line for timing. >> > >> > I'm feeding 60 Hz from a wall wart transformer into a modem control >> signal >> > that the kernel PPS stuff watches. Mostly, it works as expected, but >> > occasionally, it picks or drops a cycle. >> > >> > In order to understand what was going on, I fed the same signal into >> the >> > audio input and setup a job to capture the audio. Here is an example >> of >> a >> > pick: >> > >> http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png >> > >> > OK, that somewhat makes sense. >> > >> > >> > Something happened several days ago. I used to get picks/drops >> rarely, >> > say >> > ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I >> started >> > looking closer. >> > >> > I'm now seeing stuff like this. I've got lots and lots of examples. >> I >> > added >> > a second PC with different hardware. It sees the same stuff. >> > >> > Does anybody recognize this? >> > >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png >> > http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png >> > >> > >> > -- >> > 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.