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FM Transmitter

Ok, a few postings as I have been gone from this blog for a year. Reboot.

Above is a pic of a simple FM transmitter that picks up ambient sound in a room, such as talking, and transmits it at a frequency that can be picked up by any FM radio. Less than 20 simple parts, it works amazingly well for such a simple circuit. It contains one transistor and a microphone I salvaged from an old FRS radio. The silver wire coil is handmade, just a piece of wire coiled around a pen. This is not my invention nor is it anything new, but it is quite an effective short-range transmitter “bug” that I’m sure has been replicated thousands of times by amateur “spies.”

Posted in Electronics and Radios by with comments disabled.