Chuck wrote:
In the case of a 60Hz mains derived signal, most of the noise is going to be riding on the signal, and will be amplified with your gain stage.
The potential evils of bandpass filters in a timing chain are well known, but as long as you can accept the delay of a filter (or correct for it, which should be trivial with a PIC or other uC), you may be much further ahead with a noisy signal like the AC mains if you use a sharp bandpass filter on the incoming 60 Hz then amplify & clip the signal to increase the slew rate. Active filters with fast, quiet op-amps should do the job well. For the lowest jitter, a Collins-style multi-stage zero cross detector may be helpful.
Best regards, Charles _______________________________________________ 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.
