This circuit from a 1970s General Electric publication applies to motors of the series winding type. SCRs support current equivalents and must be equipped with heat sinks.
Found in a 90's EDN this circuit can be used as a shield. The transistor is a general-purpose type and the...
This circuit was found in the November 1992 issue of Radio Electronics magazine. The circuit has...
This circuit was found in an American documentation from 1977. The circuit can be implemented with modern...