This circuit was found in a 90’s EDN. The components used are still common and the sensors can have their quantity increased. The supply voltage is according to the relay.
This circuit is used to protect an amplifier from excessive power output that would cause problems for...
This circuit was found in a French magazine Toute LÉlectronique from 1978. Transistors are not...
This circuit was found in documentation from the 50's. The circuit uses transistors of the time...