FM radio receiver on one transistor 2SC9018

Whis is radio  called a synchronous-phase detector or, less commonly, a superheterodyne with a zero intermediate frequency.

The following is made on the C9018 transistor:

- a heterodyne tuned to a frequency half that received

- a frequency converter on two diodes, the function of which is performed by the transistor transitions. The conversion occurs at the second harmonic of the heterodyne together with the received signal

- phase detection occurs on the diodes together with the received signal

- the transistor also performs the function of a low-frequency preamplifier

The receiver can be connected to a sensitive low-frequency amplifier or a preliminary low-frequency amplifier can be assembled on one transistor. The L1 coil has a diameter of 7 mm and contains 5 turns with a tap from the center. L2 is 7 mm in diameter and has 11 turns. The coils are wound with a 0.6-0.7 mm wire. The antenna is a 90 cm wire, you need to select the antenna position for the best reception. I received almost all FM radio stations in the city on the 10th floor, some are quieter and others are louder. If the receiver does not work well during assembly, change the capacity of the capacitor C2, swap the terminals of the variable capacitor. When the receiver is working, there is an effect of hands on the stability of reception