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 simple amplifier uses a microphone attached to the telephone. The 3-transistor circuit was...
This toy organ was found in Popular Electronics from January 1967. It can be constructed from...
The circuit below was found in the March 1990 issue of Radio Electronics magazine. The circuit...