This circuit is the receiver for the previous transmitter modulated by an audio signal. The transducer is a ceramic capsule, in which case the circuit becomes ideal for telegraphic transmissions.
This simple receiver picks up local MW stations with playback on a small speaker. The antenna must...
This circuit deactivates the ignition system after a certain time when you leave the vehicle. In...
This conventional humidity or water alarm circuit was found in an English documentation from 1974....