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.
This circuit is from a 1980s documentation, but the configuration can be applied to most modern...
Found in General Electric documentation from 1967, this circuit makes use of an unusual...
Although it is a common configuration today, these circuits were taken from an old publication. The...