I use these for train speed control:
HiLetgo 12V~40V 10A PWM DC Motor Speed Control Switch Controller Voltage Regulator Dimmer for Arduino
4.5 out of 5 stars 235
And these for LED dimming:
Hiletgo 3pcs DC12-24V 8Amp 0%-100% PWM Dimming Controller for LED Lights, Ribbon Lights,Tape Lights,Dimmer is compatible with Hilight, LEDwholesaler, fillite, and others' strips
Tom Stoltz
in Maine