Wireless microphone schematic - Hobby Hour Simple wireless microphone schematic diagram. Electronics Sitemap Home Simple wireless microphone. This wireless FM microphone is simple to build and it has a useful transmitting range (over 300 meters in the open air). Despite its small component count and a 3V operating voltage it will easily penetrate over three floors of an apartment building. FM wireless microphone circuit diagram | ElecCircuit Sep 03, 2018Figure 1 Two transistors FM wireless microphone circuit. The microphone acts as the audio receiver to convert voice to an audio signal. It will come to C2-coupling capacitor into the base of TR1-transistor. Which this transistor and a few parts around itself, have 2 functions. First, they generate the high-frequency oscillator.