The purpose of this circuit is to cut off the high voltage when the bias voltage fails. The circuit is from a 1975 documentation and can be adapted for other purposes.
Based on 4066 CMOS, we found this circuit in a Popular Electronics from 1992. The signal is...
This receiver of two transistors for the 3.5 MHz band was found in a circuit manual from the 80's....
This circuit uses an unusual Motorola integrated. The circuit is from Motorola's 1990 Linear...