[time-nuts] Logging the grid frequency....
Hal Murray
hmurray at megapathdsl.net
Fri Feb 22 18:47:05 UTC 2013
dmendesf at gmail.com said:
> No, just designing a very wicked PLL and needing statistics of the
> frequency derivative... No generator is involved, it´s mains frequency (but
> you gave me another idea... thanks!).
There is a lot of noise on the line. I'm not sure if frequency makes sense
on a cycle to cycle basis.
Two suggestions:
With a transformer and a few resistors, you can feed the line into the audio
input on a PC. Then you can search for zero crossings, run it through a
filter, feed it to a FFT...
You can also feed the line into a modem control signal on a PC serial port.
(USB probably won't work.) The PPS logic from NTP will count cycles and
record a timestamp on the last one.
--
These are my opinions. I hate spam.
More information about the Time-nuts_lists.febo.com
mailing list