Found in an Electronic Design and 1970s, this circuit uses transistors of the time. The transistors can be replaced with equivalents and the relay is 12 V depending on the power supply.
This circuit was obtained from Popular Electronics from March 1967. The transistor used is from...
The purpose of this circuit is to control the high and low light of a car, detecting when a...
This circuit triggers three incandescent light bulbs following the audio signal applied to its...