Regenerative FM Receiver Using One Transistor

The VHF super regenerative receiver has been trimmed down to a single transistor without compromising its tremendous sensitivity and selectivity while maintaining the same clear audio.

The original design of the VHF receiver consists of 24 component counts which were trimmed down by taking away a single component until it reaches 12 component counts. The LM386 audio amplifying circuitry is placed near the receiver.

A homemade choke was created with a single layer tapped air core drain coil. It has a total of 7 turns with a 2 turn tap if it was intended for using a variable tuning capacitor. A total of 9 turns can be made without the use of VARIAC with 2 turn tap. The 1K potentiometer is being used for the gain control. The ON/OFF switch and the audio jack can be found on the underneath belly of the PCB which are all supported by two machine screws elevated to a height that gives the two devices enough ground clearance.

The PCB is a single-sided type where the copper is on one side of the board. an FM radio station will be received upon turning of the potentiometer.

Rest of the project