This 1967 commercial radio covers 6 wave bands selected by appropriate coils. The circuit currently uses critical components, such as coils and transformers.
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...