The resistors R1 and R2 consist of 8 220 ohms x 2 W resistors connected in parallel. The dissipation must be higher for high transmitter power. The indicator can be the multimeter.
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...