Found on a 1965 Radio Electronics, this circuit fires a signal xenon lamp applied to the SCR from an external trigger. The pulse transformer generates high voltage for flash triggering.
This basic Schmitt trigger was found in an American publication from 1968. The circuit uses...
This circuit is from an American 1964 documentation. Transistors of the time are used, but modern...
This simple circuit uses small speakers for both listening and speaking (microphone). The feeding is...