Without regulation, this basic circuit has the output current, and voltage determined by the transformer. The input can be 110 V and 220 V if the transformer used is of the indicated type.
This oscillator for the fifth overtone of a crystal was found in a Radio Electronics magazine from...
Found in an American publication from the 1970s, this circuit makes use of unusual components...
This circuit was found in the September 1984 issue of Radio Electronics magazine. The frequency is given...