There are numerous devices out there that do non-contact detection of AC voltage in wiring. The wire just has to be live and not connected to a load. Fluke sells a nice one, but I like the GVD-505A from GB instruments because it had a pot to adjust the sensitivity. It has a power switch on the pot... the Fluke has a pushbutton/LED that can be a pain to tell what mode it is in. The non-contact power detection feature is being built into a lot of new multimeters.
I also bought a couple of Chinese Fluke style knockoffs... these are dangerous since they don't always respond to conductors carrying current. The circuit seems to be a CMOS gate with a probe wire connected to a gate input. I think there was a biasing circuit / coupling cap on the gate input. Something like that may work for you... _______________________________________________ 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.
