Found in American documentation from the 90s, this circuit uses TTL technology and is therefore compatible with microcontroller drives. The circuit must be powered by a 5V power source.
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...