This configuration appears at several points in this section, obtained from different sources. This is from American documentation. The gain is 20 and the transistor can be a BC549.
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...