DC-Motor Control

=============================== A variable resistor is simple, but not effcient. Speed control can be done with one mosfet. Speed and direction requires a h-bridge... one pair of mosfets provides fwd speed control, the other pair reverse.

Look at the PWM fan noise solutions at this site:

There are several suggested methods here for controlling the speed of

12V fans, from the very simple (diodes in series to lower the fan voltage) to the more complex (PWM control).

Good luck Chris

Yeah, and make sure there is enough gap between direction change to account for Capacitance on the gates.

--
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

Buy an ESC (electronic speed control) from a RC Hobby shop. Then you can build or buy a PWM to provide the controlling pulse width.

Or..... Google for ESC circuits and build one.

Don

If he is going to build a PWM to drive the ESC, it would be just as easy to add a FET to it and control the motor directly. Duty cycle from 0 -

100% == full off to full on.

Jim

Just google "555 motor control" and you get tons of hits. For example :

Jim