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.
What differentiates this circuit from the previous one (CB15613E) is the non-need to use a...
The transistors are 2N918, 2N3464 and other RF equivalents of the time for Q1. For Q2, 2N3399, 2N2894...
This circuit was obtained in documentation on medical applications from 1966. The circuit is used in...