This circuit is from a 1978 magazine Radio & Electronics Constructor, but it can be assembled with 1N4004 diodes and TIC106 SCRs for motors up to 1A. The transformer has a secondary 12 V x 1 A.
This circuit is the conventional use of the 7805 as a constant current source up to 1 A. The...
The integrated circuit used in this application is not currently common. The circuit is from an...
This circuit is from a Radio Electronics from February 1966. The circuit is of a type that was...