Medium impedance stage (CB20563E)

We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the time.

5-Range Ammeter for DVM Module (CB25225E)
This 5-range current measurement circuit was found in the September 1989 issue of Radio...
Basic Bass Controls (CB25824S)
These basic bass controls were obtained from an article in Electronics Now magazine in February 1995....
Muscle signal simulator (CB7872E)
This circuit simulates the signal produced by a muscle, serving to adjust medical equipment. The circuit...