This timer was found in English documentation from the 80's. The integrated circuit is common nowadays and the MOSFET admits equivalent according to the controlled load.
This circuit for controlling high power in the AC network was found in a Motorola documentation from 1968....
This amplifier is specifically designed for portable radio and recorders with a 4 ohms load....
This circuit was found in a 1973 Radio Elettronica magazine. The Italian magazine no longer...