This circuit that has a response from 10 Hz to 700 kHz was found in Philips documentation from 1968. Dual transistors can be replaced by matched pairs.
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...