Found in documentation from 1924, this 4-tube circuit has a heterodyne amplifier, as it was called.
We found this circuit in a 1977 Radio Shack manual. The light bands are given by the operating gain...
The circuit in the figure is a current regulator with adjustment in the range of 0 to 3 amps. The...
This stage for JFETs was found in a 1965 US publication, but is valid for modern components. |...