This circuit generates sinusoidal signals between 300 and 3000 Hz. We find a 303 Circuits from the 90's. The operational ones are types with FET. The power supply must be symmetrical.
This timer, from an old American publication, uses indicator lamps, but can be modified to use...
This LED special effects circuit was found in the February 1992 Radio Electronics magazine. The...
August 2016 - It can be obtained from Mouser Electronics MDS adapters for medical use from Delta...