Suggested by General Electric in a 1968 documentation this integrated amplifier uses a component of the era, the PA237. The circuit runs on 24 V and excites a 16-ohm speaker.
The purpose of this regulator is to regulate the RMS voltage in an alternating current load. The...
This circuit can use almost any operational amplifier and the FET can be the BF245. The circuit...
Found in a Motorola documentation from 1965, this circuit consists of an electronic ignition with a...