Suggested by General Electric in a 1970 documentation, this circuit makes use of some components of the time, in the case of transistors. The circuit detects smoke by the transparency changing of the air.
This circuit shows how to use common logic functions to divide a frequency by 7. The output signal...
This circuit can be used in alarms, data links or áudio links using IR radiation. The circuit is...
This circuit was obtained from an American 80's documentation. It can be implemented with modern...