Found in a 90s Popular Electronics, this circuit checks if a remote-control transmitter is emitting signals. The sensor is a general-purpose type found in many electronic devices.
The existence of field effect transistors at the input of the integrated circuit (operational...
This circuit has a maximum output current of 5 A, and the 2N3055 must have an excellent heat sink....
This circuit is suggested by Motorola and is based on a 1723 voltage regulator. The 2N3055...