I've moved the 60 Hz stuff from http://www.megapathdsl.net/~hmurray/time-nuts/ to http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/
---------- The main graph is now up to sightly over 4 days. http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz.png Peak-to-peak is almost 8 seconds. The slew rate is pretty fast in a few places. 1 second in 1/2 hour at hour 64. 4 seconds in 3 hours at hour 13. 2.5 seconds in 3 hours at hour 44. 7 seconds in 7 hours at hour 91. ---------- When I started, I picked 10 seconds as the sampling rate. That was just a wild guess, but it seems to have worked out well. That's 1/2 megabyte per day. (I think I can trim a factor of 2.) I plotted the frequency. It's not as clean as the offset. Here are 3 graphs, measured over 10, 100, and 1000 seconds. http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-f10.png http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-f100.png http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-f1000.png Note the two big spikes on the 10 second graphs. Those correspond to 2 glitches in the raw data. Both have 3 extra counts within a 10 second sample slot. http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-g1.png http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-g2.png Note that they are close to 24 hours apart, at 6:30 to 7:00 AM Pacific local time (California). Has anybody noticed things like this? As a sustained slew rate, it's huge relative to the longer samples above. But maybe steps like that are normal transients when somebody throws a big switch. Or maybe they are glitches due to lightning/whatever. I guess I'll have to connect up the audio port and grab a lot of raw data so I can inspect the area around glitches like these. ---------- This is the (python) code I'm using to collect the data: http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz.py Edit daemon to 0 if you want to debug things. It's got my directory hard wired in it. (That should be easy to fix.) If you improve it, please send things back to me and/or put your version on the web. It's a quick hack, don't expect elegance. It uses some Linux specific tricks. I'll work on a version in c that will probably run on *BSD if anybody wants it. ---------- The raw log files include the 10 second deltas. This is the hack I use to compute the 100 second and 1000 second data. http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/stretch-60Hz.py If anybody wants it/them, I'll put the gnuplot files I use out there too. -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ 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.
