i mean, is there a such thing as like an airplane junk yard ?

Go to fly-ins (there's a really big one in Florida April 4-10 called
Sun'n'Fun, but smaller ones happen all the time). But you need to know
what you're buying, and whether it's really suitable for what you want.

Newer aviation units use 28 volts (or even 48 volts IIRC) but there are
older ones that use 12 volts. I don't know if the frequencies of the
marine transmitters are compatible with the aviation units.

Jose
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