This circuit makes use of a specific 80's component and was found in an American manual of the time. A matrix keyboard allows you to select one of several music programs.
This circuit was found in a publication of1994, originally obtained from the National...
This circuit was found in a 1977 Radio Shack documentation. The circuit is TTL, which must be...
This circuit was found in an American 1980s documentation. It analyzes the exhaust gas of a...