In article ,
andy12345 wrote:
Mark:- I am in england and therefore on a 50 hz system and could
potentially be coupling that into the microphone. I am not holding
it, but, it is on my headphones set isolated by some headphone
padding. Can it couple under such circumstances?

Is the comms unit self powered? Ie by a wall wart? If so it's likely to be
double insulated so no *safety* earth required. So what you're dealing
with is an audio ground. Is the casing of the mic connected to the screen
of the output cable? The mic *might* be a balanced type with the screen
floating.

--
*I don't suffer from insanity, I enjoy every minute of it *

Dave Plowman London SW
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