Found in a PE Hobbyst Handbook of 1991, this circuit was originally proposed to time photographic baths in developing rooms but can be used for other purposes. The circuit beeps at 30-second intervals.
This small blocking oscillator for approximately 1000 Hz was found in an American documentation from the...
This isolated solid state relay can function as a shield directly controlling 10 A loads. The...
This circuit was found in a 1974 publication. It converts the applied voltage into pulses of...