Found in a 1967 American electronics magazine, this circuit has an input impedance of 2000 ohms. The circuit can be built with modern equivalent transistors.
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...