This circuit was obtained from the April 1978 Radio Electronics magazine. The other circuit is a PLL of the time. The power supply must be 15 V symmetrical.
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...