Here is a simple mod to allow the speed of any 12V fan to be varied. All we need to do is insert a rheostat or variable resistor in the 12V wire to the fan. The rheostat should be rated at least 3 ...

Why get up close and personal with a resistor when you can tweak it from a distance? Remote variable resistors make analog circuit control easier, neater, and a lot more fun. Well, we are about to ...