This circuit amplifies signals from 0.5 Hz to 300 kHz. We found it in an old documentation. Equivalent transistors may be used. The gain is 20 dB.
This circuit was obtained in 1974. It serves to indicate the tuning of stations on a common...
This circuit was found in American documentation from 1966. It uses a hall effect sensor at the...
This stage for general purpose transistors was taken from an old technical manual. The circuit can...