PWM The PWM speed control does not work well with a light load such as a 12V fan. There's a narrow window in the adjustment potentiometer that does just about anything, slowing down slowly to the death. Turning it on out of nowhere makes it difficult to get something and then suddenly turn on. You could use a sonic cone potentiometer, but that's something for people who grew up with electricity. More Chinese junk. May work in your application.
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