This compact, sensitive, communications receiver has a tuning range of 80 to 135 MHz, covering part of the VHF-low band, the entire VHF broadcast band and the VHF air band. The upper frequency limit of the receiver can be changed fairly easily to include the 2-meter amateur band.
The following schematic shows the AM/FM VHF Receiver Circuit and Block Diagram. The RF section, comprising the RF input amplifier, the mixer and local oscillator, is of conventional structure. An integrated circuit provides the necessary IF amplification, and at the same time comprise the AM and FM demodulators. A squelch circuit, built from discrete components, works in AM as well as FM mode.