This circuit was obtained in a 1968 manual of General Electric. The components used are of the time, but they admit equivalent. Observe the optical feedback system for control.
We found this circuit in the April 1975 Radio Electronics magazine. The circuit has a latch and...
We found this sophisticated home alarm in a 1994 documentation. The circuit supports sensors of...
This circuit was found in the 1991 Electronics Experimenter's Handbook. It activates a relay when...