Washed Phenom wrote:
Partly for the fun of it, and also for practical uses, I'd like to
design a receiving system whereby a small transmitter could be
located. This would not technically be a "tracking" situation, since
the transmitter would not always be on. I'm imagining something like
a garage door opener, where pushing the button can send a brief (but
very strong if necessary - this may have power implications?) signal.

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73, Markus HB9BRJ