This current switch was found in a Radio Electronics from November 1957. It triggers the current determined by the electromechanical sensor, a polarized relay of the time.
This circuit is from a 2001 publication. The balun transformers are of the commercial type for TV...
This circuit is from an old publication from the 1950s. The circuit uses germanium transistors but can be...
This amplifier, from the 1990 Philips Databook, is suitable for automotive applications. The...