Seams like some people are having problems with noise using the RS Wireless Mic set up. I have made several of these wireless e-callers and the only time I have had noise problems is when the batteries are getting low. If you are using a mp3 player or any other unit that is a stereo unit you may have to us a stereo phone plug instead of a mono phone plug to connect the transmitter to your player. I have always used a mono cassette player/recorder. I hope this helps.
Good Hunting,
Jim
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Good Hunting,
Jim
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