Found in an American publication from 1947, this 4-tube amplifier has excellent sound quality. Its source makes use of a transformer.
This simple PWM circuit was found in the March 1991 issue of Radio Electronics magazine. The...
This circuit divides the grid 60 Hz frequency to obtain 20 Hz to drive mechanical watches used at...
Originally, this circuit is from an English magazine, but I found it in Argentina's Radio Chassis...