We found this circuit in a 1967’s Electronics World. The circuit can be made with modern equivalent transistors. The selection is made by the tuned coil.
Found in a 1980s documentation, this circuit uses as base a component of the era. The formula for...
This circuit divides the voltage of a 12 V battery by 2 and can supply currents up to 1 A at the...
The transistors of this 12 V x 150 mA power source can be BC558 for PNP and BD135 for NPN. The...