This circuit was originally suggested in a 1968 publication to generate a white mark (frame) on a film at regular intervals to serve as a time reference.
This QST circuit generates 4 frequency signals according to the crystals used. Transistors admit...
This countdown electromagnetic ring launcher was found in an Electronic Hobbyst Handbook from...
This TTL circuit was found in an American documentation from the 80s. The components are common in the...