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.