Found in a 90s Popular Electronics, it serves both TTL and CMOS logic. The injector can provide 10 kHz or 100 Hz signals. The circuit drives a transducer and two LEDs.
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....