This circuit is from an1966 General Electric documentation. The Triac can be equivalent to 6 A or more, mounted on a good heatsink. Any diac can be used.
This preamplifier circuit for turntable cartridges was found in the March 1994 issue of...
This circuit is from an American 1964 documentation. Transistors of the time are used, but modern...
This siren was found in a 1980s documentation. The circuit makes use of very old operational that were...