This Japanese transistor radio was manufactured in the 1960s in Japan. The circuit of 6 transistors is for the medium wave range and is powered by a 9 V battery.
This circuit of a 1978 American publication monitors a telephone line by triggering a relay. The...
This interesting FET-tester circuit was obtained from an old American documentation. The bipolar...
This old VHF TV booster that also serves FM was found in Radio Electronics magazine from April...