Simple FM Transmitter Circuit

Simple, Easy to Build FM Voice Transmitter Circuit

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Simple FM Transmitter Circuit 88 to 108 MHz
An easy and simple to build FM (Voice) transmitter circuit that operates in the 88 to 108 FM band, or into the VHF bands, if the turns on the inductor are decreased.
The 4.7 to 22 pf trimmer capacitor in conjunction with the 0.26 uH inductor (Estimated) allows the frequency to be adjustable in the 88 to 108 MHz band.

The inductor can be 5 or 6 close wound turns of # 18 Magnet wire, air wound around a 3/8 inch drill bit. Output power can be increased by decreasing R4. The antenna is a piece of small wire, or flex wire around 18 to 20 inches. For operation into the VHF 147 to 174 MHz range simply decrease the turns of the inductor.