This circuit was found in a Hands On Electronics from the 90s. It is intended to supply old tape players to batteries with a voltage of 7.5 V from the 12 V of a car battery or source.
The purpose of this circuit, found in a documentation for radio amateurs in 1974, is to amplify noise...
Found in an Elektor from the 90s, this circuit simulates a rotary switch that provides a BCD...
Found in a 1970 American publication, this circuit uses transistors of the time. These transistors...