This commercial transistor tester circuit (EICO 666) is from a Japanese publication from the 1960s. The switch selects the types of test with the switching of the terminals and the gain ranges.
This circuit allows you to use a calculator as a timer by directly activating a sum key with...
This “Half adder” circuit uses NAND gates from a 7400. The power supply must be 5 V. ...
ECL logic circuits can operate at very high frequencies. This circuit was obtained from a 1977...