This circuit was found in a 90’s EDN. The components used are still common and the sensors can have their quantity increased. The supply voltage is according to the relay.
This is a circuit from the 1950s, from the time when the transistor was still called by some...
Found in a 90s Electronics Engineering, this circuit makes use of components of the time. The...
This is a simple voltage tester for voltages from about 2V to about 15V with the indicated...