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 generates signals from 0.01 Hz to 10 kHz, but uses unusual components today. The...
This 1969 Mullar circuit appears elsewhere on this site. The circuit uses germanium diodes and the...
This control circuit for direct current motors uses a 741 and an operational one of unusual power...