Jim, most of us are satisfied to use a 6.3VAC filament transformer to step down from 120VAC and isolate from the power line.
Tim N3QE > On Jul 2, 2019, at 5:56 PM, jimlux <jim...@earthlink.net> wrote: > > There's some designs on the list (using a PICPET, for instance) to measure > the local line frequency and phase.. > > but the schemes we've discussed require connecting to the power line in some > way. > > What about a non-contact sensing approach? Something you could put in a box > and it would pick up the electric or magnetic field as the input? > > Just how strong is the field anyway? I've always been trying to cancel or > shield it or reduce it in some way, so I've never actually measured it in a > calibrated way. A 10cm antenna on a 1Meg scope probe looks like about 40 mV > peak to peak (for the 60 Hz component) along with lots of other high > frequency stuff (40 kHz and a few hundred kHz in my office) from switching > power supplies. > > I realize that in a office/industrial area you'll probably pick up all three > phases in some way. > > What about using a small loop? or a magnetoresistive sensor (like the > compasses in phones)? > > Has anyone tried any of these? > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
