This circuit was obtained from the Encyclopedia of Electronic Circuits volume 5 of 1995. The circuit uses the 4001 CMOS to obtain hysteresis in the sensor feedback.
In the figure we have a typical polarization circuit for MOSFETs with a high impedance...
Equivalent transistors, like the BC548 and BC558 pair can be used in this circuit that we find in an...
The circuit presented is from an old magazine having been translated and published in a national...