We found this configuration in a 1974 publication. Transistors can be replaced with equivalents such as 2N2222. The circuit has a dynamic range of 60 dB.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...