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Is there an easy way to control the speed of a little 6v motor? Answered

I've got a little 6v electric motor that I would like to slow the rpm's down.  It doesn't have to be a variable controller, but if there is something like that then cool.  I'm just looking for a cheap way to slow that puppy down.  Any info would be greatly appreciated.  :)  (p.s. I'm using the power from a USB - 5v)


Using a simple resistor isn't a very good way to do it, the ability of the motor to run well under load is compromised. Its always better to use a regulator.

You might do this with a transistor and a few other bits.



Well really that's just a glorified resistor. Steve

Yes it is (I don't think it's ideal at all) but I was thinking of cheap and simple, and not just a "volume control".



8 years ago

I have used the volume control from an old transistor radio as a speed controller. If you can get your hands on an old radio or an old Walkman or similar device with a volume control, it might do the job.

So is that basically just controlling voltage to the motor? (p.s. thanks for the tip) Is there a part at radio shack that will do the trick?

Yep, that's precisely what it does.
I would assume that you can find something a RS. Look for a variable, low voltage resistor or a rheostat.

No it isn't, it controls the current too. DC motor speed is controlled by the applied voltage only, but the speed regulation is determined by the resistance of the motor. Adding resistance screws the regulation.