This circuit appeared in the September 1973 issue of Radio Electronics magazine and was recommended for a synthesizer project. The circuit is for audio signals and has control inputs.
Using a CA3130 operational amplifier, this circuit was found in an English publication from 1977....
The purpose of this circuit is to transmit the signal from a guitar pickup to an FM receiver...
This direct coupled circuit operates in class AB with good gain. The circuit is powered by 12 V....