Found in a 1970 American publication, this circuit uses transistors of the time. These transistors may be replaced by current equivalents. The factor Q is greater than 3 000.
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...