This commercial earphone receiver was manufactured in the 1960s in Japan. It was powered by a 9 V battery and the transistors were made of germanium.
This TTL circuit found in the September 1996 issue of Electronics Now magazine doubles the...
This key is turned off by a touch sensor. The time it remains active depends on capacitor Cx. The...
This circuit is from a 1967 publication and applies to incandescent lamps up to 600 W. Triacs must be...