Found in old American documentation, this circuit is intended for the control of heating elements. The SCR must have current according to the controlled load. Transistors are from the time.
The S-meter is signal strength meter, coupled to telecommunications receivers to indicate the...
This circuit is suggested by Motorola, making it possible to use an optical coupler of type 4N26...
Dynamic analyzer is another name given to a signal follower or signal chaser. This circuit is from...