Re: signal leads that pick up less ambient noise?

Christopher Howard <christopher@librehacker.com> wrote:

Frequency??

 
I'm not sure exactly, but when I zoom in to it on the scope, the noise
appeared to have a regular ebb and flow of about 40 Khz.
 

That seems very likely to be from some power supply, either wall wart or
built into some equipment.

A great EMI sniffer to sleuth out is an old school $5 pocket AM broadcast
radio (the kind slightly larger than a cigarette pack and powered by 2 AA
or 9v block battery).

--
piglet