We found this circuit in a 1967 documentation. The integrated circuit and an operational one of the time. Modern equivalents can be tried out. The power supply is symmetrical.
The drive levels of this shield are opposite to the previous one. The photo-transistor can be of...
This circuit was found in a Radio Electronics of July 1984. It consists of the traditional 1 A...
This flasher or neon signal powered by batteries was found in old documentation. The transformer must...