Found in an Electronic Design from the 90s, this circuit provides outputs according to the input following the truth table given next to the diagram. The various options are shown.
This circuit for VCR recording heads was found in the February 1990 issue of Radio Electronics magazine....
This very simple continuity tester uses a small 1.5 V lamp (type used in flashlights). Can be...
This commercial radio with 3 earphone listening transistors was manufactured in Japan in the...