This circuit indicates when a 28 V lamp burns, lighting a neon lamp with higher voltage. The circuit is from 1969 documentation.
Found in an Electronics World of 1969, this circuit generates 400 Hz signals. The coil must have 3 H...
The quiescent current of the small transmitter is around 20 mA. The transmission frequency depends on...
Vox or sonic switch is a relay activated by the voice or any sound picked up by the microphone. This...