jh wrote:

Thanks for the tip. I'll try both ideas (when I get a chance; it might
be a while) and post anything interesting. I'm hoping to eventually
(maybe after I learn more about electronics) build a reasonably
sensitive EMI-only "microphone" to use as a sort of computer
stethoscope.

I'd second the coil idea for that.


Here's my idea: could a computer technician, with this tool and some
practice, hear and immediately recognize the EMI signature of a dying
power supply or other bad component, the same way an expert pilot can
instantly diagnose engine troubles just from their noises? Certainly,
many technicians recognize the distinctive sound made by some dying hard
drives; but most components don't make any noise that we can hear
naturally.

-- Josh

To some extent. One very handy tool is a little hand held buffer plus
pizeo, apply it to various points and you hear whats going on. The info
you get is limited, but presented fast and easy. You can differentiate
data from no data, real data from fixed frequencies, dc from ac, steady
frequencies from unsteady, intermittent signals, and so on.

A coil picking up everything at once.. not sure how the total mishmash
of all those sources blended together would tell you that much, other
than go/no go.


NT