FM Transmitter

Circuit : Andy Collinson
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A small FM voice transmitter for Band 2 VHF. It can be tuned by adjusting the turns on the coil.

fm transmitter circuit Notes:
This small transmitter uses a hartley type oscillator. Normally the capacitor in the tank circuit would connect at the base of the transistor, but at VHF the base emitter capacitance of the transistor acts as a short circuit, so in effect, it still is. The coil is four turns of 18swg wire wound around a quarter inch former. The aerial tap is about one and a half turns from the supply end. Audio sensitivity is very good when used with an ECM type microphone insert.

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