The purpose of this circuit is to indicate which of the two cars crosses the finish line first on a slot car lane. The circuit is from an 80's Popular Electronics.
This circuit was found in an old Electronic Design. It makes use of sidacs and operational not very...
This 2009 circuit is a bilateral call warning. Easy to build, using light communication between two...
This circuit for shunt motors was found in an American 1980s documentation. The SCR should be rated...