This dynamic mixer allows for smooth adjustment of the signal's passage from one channel to another. We found it in an American documentation from the 70s.
This circuit for experimental radios and other applications is from a documentation from the 50's....
This circuit was found in a Popular Electronics from the 90s. The circuit uses general purpose...
This 20 Hz high-pass filter was obtained in a 1965 American publication. The operational amplifier must...