Self-biasing JFET circuit (CB25563E)

This JFET amplification stage was found in the April 1993 issue of Electronics Now. The input impedance is 10 Megohms.

Thermostatic relay (CB21285E)
We found this circuit in an old QST magazine. The circuit is powered according to the thermostatic relay...
SCR circuit breaker (CB8901E)
This circuit was found in a 90s Popular Electronics. The components are from the era. R3 must be...
Analog Multiplier (CB7930E)
Found in a 1968 EEE, this circuit accepts frequencies from 1 to 1000 Hz and control voltages from 0.1 to...