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Old 07-04-2021, 09:45 AM
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blackshire blackshire is offline
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Join Date: Jan 2009
Location: Fairbanks, Alaska
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Quote:
Originally Posted by dannymrmissile
It is one of the Microphone Accessories. There’s 2. One was opened. This is a sealed bag of the contents. It’s an earphone. I thought it was an old Hearing Aid. But it’s for use in the field when an external speaker isn’t being used. First one I ever saw. Very rare.
I imagine so. Thank you--yes, those crystal earphones can be used "in reverse" as microphones (just as speakers serve as microphones in some speaker phones). I'd prefer an electret condenser microphone for better audio quality, but those crystal earphones are much cheaper. If the schematics of those accessories aren't already online (the basic transmitter's schematic already is), they should be; all of those units are easy to make at home.
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