Medium impedance stage (CB20563E)

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

Negative high voltage source (CB8122E)
We found this circuit at Popular Electronics. The components are still current. Changes can be...
Digitally Controlled Astable (CB5424E)
This circuit, which can act as a shield, is from old documentation, using a DAC of the time. Next to...
6 to 9.5 W amplifier TDA1010 (CB15978E)
This integrated contains a Class B circuit originally developed to provide 6 W in a car radio...