Found in an 1868 Mullard documentation this circuit has a dynamic range of 10 Hz to 25,000 Hz. Modern equivalent transistors can be used.
Suggested by Motorola documentation from the 1980s, this circuit can be implemented with...
This circuit, from a publication of the 1970s, can compare the intensity of two light sources,...
The circuit shown bellow is na áudio amplifier using Darlington transistor in a complementary...