The circuit shown has a voltage gain of 500 times and can use equivalent FETs like the BF245. The circuit is suggested by National Semiconductor in its 1994 Linear Applications Handbook.
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...