FM Transmitter

Source :: http://www.zen22142.zen.co.uk/Circuits/rf/davidtx.htm

Circuit : David Sayles
Email: All enquiries via anc@mitedu.freeserve.co.uk


Description:
A small FM voice transmitter for Band 2 VHF

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.