This game aims to make you discover which is the combination of activated switches that make the LEDs light up. The circuit is powered by batteries or cells.
This circuit monitors an old-style analog telephone line. We found it in the September 1991 issue...
This circuit was found on a Radio Electronics of July 1984. It consists of a source with the 741...
This circuit, found in an old magazine of the year 1968, uses a Power germanium transistor. This...