This is an amplifier circuit intended for modulating transmitters. The 5-tube circuit is from an American manual from 1947. The power supply uses a transformer.
This is a traditional commercial circuit that can be assembled if the reader finds the components used....
This Power supply is intended to Power small loads with currents up to 30 mA. The voltage depends...
This code key uses a PLL and an oscillator that generates two frequencies that must be recognized for...