This circuit is from an American documentation from the 90s. The transistors are of power and must be equipped with good heat sinks as well as the integrated voltage regulator.
This control for 1200 W of power was found in the documentation of General Electric of 1966 has a...
I found this circuit in an old English magazine from 1979, but it can be easily assembled with...
This circuit imitates the singing of a bird intermittently with the intermittency determined by C1...