This circuit was found in a 1964 Electronic Design. The transistors are of the time, but can be employed as modern equivalents. The system is for car with contact breaker.
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...