"cpemma" wrote in message
...
A E wrote:
Dave D wrote:


Anyway, the best way to control one of these brushless motors IMO is
a LM317 or similar
regulator with a pot so the OP can set the exact speed he wants. Not
the simplest way but a sure way of getting the speed right.

Simple enough, though. 5 parts, and we can all agree on that! (input
cap, LM317, output cap, resistor, pot) This is more complex than
required. Maybe the OP can just remove half the fan's blades
instead...

Snag with 317 is that 1.5-2v loss; better method with a 0.75v loss and 3-4
parts ;-)

http://www.cpemma.co.uk/ef.html



Alternatively the TL431 adjustable zener driving a pass transistor. (The TL
431- aren't they a great little device ;-))

Dave