This sequential circuit of LEDs was found in a Popular Electronics from the 90s. The circuit can be programmed and an adaptation consists of using optical couplers to drive power loads.
This circuit is one of many that the reader can find in this section for testing crystals. The...
I found this circuit on a December 1976 Radio Elettronica. The Italian magazine no longer exists, but...
June 2017 - Mouser Electronics has in stock the new AC Metallized Polypropylene Film Capacitors...