This circuit appears on this site from different sources. This is from documentation from the 1980s. The operating system used is uncommon and can be replaced by a more modern equivalent.
This circuit was found in a Radio Electronics from October 1952. The circuit equalizes the sounds...
This circuit can function as a circuit breaker or current switch opening with a current according to...
The supply of this circuit can be done with voltages from 8 to 28 V and the maximum output current is...