Posted by Circuits99 on July 23, 2018
FM Transmitter Bug Circuit Diagram Using BC548 Transistors is the artlcle explaining FM Transmitter Bug Circuit Diagram FM Transmitter Bug This small FM Transmitter Bug Circuit Diagram uses a Hartley type oscillator. Nor...
FM Transmitter Bug Circuit Diagram
FM Transmitter Bug
This small FM Transmitter Bug Circuit Diagram 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. FM Transmitter Bug using with BC548 Transistors