Motor Speed Controller, LED Dimmer, Heat controller, voltage controller for an electrolytic etcher etc.
I did some hunting around on the interweb and found a pretty good starting point in Circuits Today, but then, I needed to make some modification and tweaking of the circuit. I wanted to add in a toggle switch, a DC power socket and a 2 pin screw terminal into the design to make it easier to make and use.
12V NE555 PWM Controller – [Link]
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