Found in a 1967 American electronics magazine, this circuit has an input impedance of 2000 ohms. The circuit can be built with modern equivalent transistors.
This circuit was found in a Philips documentation from 1970. The components are of the time,...
This circuit divides the frequency of a 2 kHz signal by 2. The circuit was found in Philips...
This circuit was found in an English publication. The components are current, and the transformer must be...