This power supply was featured in the December 1973 issue of Radio Electronics magazine. This type of circuit was used at the time to power tube televisions.
For those who like experimental circuits, here is a sequential flasher system with LEDs, which can be...
This circuit was found in an ancient American documentation. The integrated circuit is of the time...
This circuit was found in a 1977 Radio Shack documentation. The circuit is tuned to 1.4 kHz, but...