This circuit is from an American documentation from the 90's. The SCR can be of any type and the diodes must have current according to the controlled motor.
In the 70s, Ibrape launched an excellent audio pre-amplifier kit to be used in amplifiers of the...
This amplifier stage was found in a 1956 Sylvania manual and has an unusual configuration with a...
Found in a QST magazine from the 90s, this powerful unit is intended to supply a VHF transceiver for...