Found in a Popular Electronics from the 90s, this circuit activates a recorder for automatic recording of telephone calls. The circuit was used with old cassette recorders of the time.
We found this circuit in an old American documentation. Transistors can be modern equivalents. ...
In the figure we have the conventional configuration of a differential amplifier with the...
This 8 A high output power amplifier uses two National Instruments LM12s. The maximum capacity of the...