This amplifier for recording heads was found in a Radio Electronics from September 1963. The circuit uses period transistors but can be modified to work with modern transistors.
This simple circuit makes it possible to test diodes and transistors for generating use and medium...
This 2.5 A power supply was found in a 90's QST magazine. The power transistor must be mounted on a...
This circuit is a digitally controlled variable capacitor. We found it in American documentation from...