This small tube amplifier appeared in Radio Electronics magazine in February 1958. The circuit is powered by the mains with a power transformer and output with different impedances.
The circuit in the figure is suggested by ST Microelectronics (www.st.com) and consists of a...
The transistors of this circuit may be the BC548 or BC549 and its power supply can be performed...
This circuit is from Mullard's transistor reference manual from 1960. The circuit will also work...