Thread: Detecting Ultrasound
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Old March 10th 07, 11:46 PM posted to rec.radio.amateur.homebrew,sci.electronics.design
John Smith I John Smith I is offline
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Default Detecting Ultrasound
John Smith I wrote:
wrote:

...

Do you really want to hear it, or have a "field strength
indicator"/locater?

Why not just a mike capable of "hearing" the ultrasonic freqs in
question--feeding an opamp and meter?

Pointing the mike around should lead you into the correct direction and
following the meter reading should lead you to the source(s).

Possibly can substitute a light or even a led in series with a pot and
use a visual indication of strength ...

JS



Come to think of it, wouldn't take much more to square up the sine wave
out of the opam and drop a cmos decade-divider onto that output of the
opamp and feed an ear phone with the dividers output--30,000 becomes
3,000 hz--easily "hear-able!"

JS
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