This very complex circuit in terms of the number of transistors was found in Radio Electronics from March 1966. The circuit is for low impedance headphones. The transistors are from the time.
In the figure we have a high stability voltage reference, providing a voltage of 10 V at the...
We find this circuit in an American 1980s documentation. Integrated circuits are uncommon today as...
The diagram is from a 1990s document. The integrated circuit must be equipped with a heat sink. The...