Found in a 1968 Mullard manual, this circuit can function as an infrared audio link. The transistors can be the BC548.
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...