This power stage with two transistors was found in Radio Electronics magazine from October 1963. The transistors must be equipped with heatsinks and the supply voltage is 12 V.
We found this circuit in a 1976 documentation. The FET can be BF245 or MPF102 and the power supply...
This circuit was obtained in a transistors manufacturer's manual from the 90s. The circuit uses an...
The instrument of this field strength meter, from a 1970s publication, can be a 200 uA...