This circuit, with printed circuit board, is from an article in Radio Electronics magazine from May 1971. The circuit uses the C106 which was already a common component at the time.
This circuit was found in a 90s Popular Electronics. The circuit uses several relays in order to...
This circuit was obtained in an old manual valid for practically any type of operational...
This bank of switches can be programmed in a variety of ways for logic experiments. The circuit is from...