This circuit triggers a relay when a light beam that hits the phototransistor is cut off. The circuit is from Electronics Now and the supply voltage depends on the relay voltage.
This is the receiver circuit for the previous transmitter. The range of the system can reach 100...
In this game, whoever tightens the sensors, which are metal bars or spent batteries, makes the...
This circuit is from an ancient American documentation. The T-Bridge circuit determines the...