We found this circuit with JFETs in a Radio Electronics magazine from June 1969. The circuit has its assembly described in a complete article. Equivalent transistors can be used.
This circuit controls a heating element with voltage from 6 to 30 V and current up to 3 A from...
Indicated to operate in tube circuits, this preamplifier has 250 V power supply. The circuit is...
We found this circuit loader in a French magazine Electronique Radio Plans from July 1993. The...