This is a description on how I have converted my Super Regenerative Receiver into a powerful pulse counting VHF/FM Superhet Receiver. It works in the same way as my present 6 Valve FM Tuner Design but uses Solid State circuitry and is battary powered using a 9V supply. 1 2N3819 FET is used for the RF amplifier which is a grounded gate untuned stage. The Frequency Changer is a Super Regenerative Detector and is used in normal regeneration mode to form an autodyne converter which functions as a self oscillator and mixer. The reason why this is possible is because the 250KHZ IF has little difference in Frequency seperation and only 1 RF coil is needed. The IF stages are resistance coupled amplifiers consisting of 4 BC548 Silicon Transistors The final limiting amplifier shapes the IF signal into a clipped waveform and a 2 OA90 Germanium Diodes form a voltage doubler demodulator to recover the FM signal. This receiver is despite its drawbacks, like somtimes having to maintain the oscillator regeneration control when tuning from one end of the band to the other is capable of very good sound quality and works very well on the Kitchen table using the short telescopic antenna. This is now a construction project on my following webpage [ Ссылка ] . It is also my most sensitive of VHF/FM receivers I have designed to this very day and very recommended for newcomers who have never had any experience in VHF circuits. Also the circuit diagram for the tuner section can be found at the following link [ Ссылка ] and the audio amplifier circuit is the following [ Ссылка ]
