High impedance stage (CB20564E)

This high input impedance amplifier stage was found in a 1963 documentation. The transistor germanium of the time.

Neon Audio Oscillator (CB11535E)
This circuit was originally designed for the practice of Morse code, something common in 1966, the year...
DC Motor Control (CB10245E)
This circuit is from an English magazine of 1977. The circuit is still current, just using a TIP41...
Model contol (CB22185E)
This miniature railway control circuit was found in an English documentation from the 1980s. The...