jopes said:
what did you use for yours? Got any pictures?
No pics yet. I went to Radio Shack and purchased a package of 5 4.7K Ohm resistors (about $1), a douple pole-double throw switch (double pole isn't needed, but I might do some further "experimenting" with LEDs), a 10K potentiometer, and a "project box."
I have the double throw switch so I can have a high (power) and low setting. High setting has one of the 4.7K resistors in series with the pot. The low setting has three resistors in series with the pot. This gives the high setting a resistance of 4.7K-14.7K while the low setting has 14.1K-24.1K.
I wired all of this up in the project box to make it look nice and neat. I plan on using velcro or something similar to attach it to the dash.
Radio Shack didn't have a 20K pot that I wanted, so I went with the double throw switch. If I had a 20K pot, I would have just put one 4.7K resistor in series with it along with a single throw switch.