This circuit from a Radio Electronics from October 1965 shows how to obtain the action of an SCR when triggering a relay using two transistors. The relay is according to the circuit supply voltage.
This circuit can be used as an input shield by removing the signal directly from the second port,...
This sensitive circuit was found in an Electronics Hobbyists Handbook from the 1990s. The circuit can...
We found this circuit in an 80's documentation. The circuit has a gain of 30 dB and uses a varicap...