Amplifier with different output (CB9057E)

This circuit was found in a 70s National Semiconductor manual. It has a different output way for coupling to the speaker.

Two Transistors Shield or Interface (CB15484E)
The configuration shown in the figure uses two NPN transistors activating the load when the input...
13 V x 10 A power supply (CB17628E)
It is a 13.8 V x 10 A regulator obtained in a 2008 documentation. The 2N3055 transistors must be...
UJT Mini timer (CB16454E)
This timer of 10, 25, 45 seconds and 5 minutes has its times selected by the keys. The circuit drives...