This circuit was found in a 1967 US documentation. It shows how to build a gain control by digital signals. The circuit can be used as a shield. FET can be a modern equivalent.
In this game, whoever tightens the sensors, which are metal bars or spent batteries, makes the...
This two input simple mixer uses two transistor and can b e upgraded to more inputs. Input...
This circuit is from a 1987 American publication called Electronics Handbook. The circuit can be...