This circuit was found in a 90s Electronic Engineering. The quadruple operational amplifier can be replaced by an equivalent. RL determines the tested resistance range.
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...