This passive circuit was found in a 1980s documentation. The circuit serves to indicate the balance or balance between the channels of a stereo amplifier.
The idea of this simple circuit is to use a tape recorder to key a transmitter in code emission....
This amplifier was found in an 80s component manual. The circuit can be used for media recovery....
September 2016 - It can be obtained from Mouser Electronics the FAN602 integrated circuit...