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 current meter with many scales was found in a 80s American documentation. The operational amplifier...
This dimmer, from an old publication, can use almost any triac and in shooting a neon lamp. The...
We found this circuit in a 1975 publication. The circuit can be made with more modern equivalent...