Quote:
Originally Posted by LMH
You could try a rheostat from Radio Shack or similar place and see if you can put the correct knob on it. You'll need the correct ohm range which I'd say is 0-12.5 based on the ad from Holden.
Would be a lot cheaper for sure.
Larry
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Rheostat is an old and automotive term. The term under which you'd find these things in a modern electronics supply house is "potentiometer."
You can't use an off-the-shelf pot for this job, as most are rated at only a few watts of power and will burn up at lower settings with an amp or two of lamp bulbs downstream. The ones used in cars are "wire-wound" pots (or rheostats) - it's the slider moving over those wire windings that gives the knob that "gritty" feel. Wirewound pots can handle 10, 20, even 100 watts depending on size and rating.
I think you'd have trouble finding a suitable one for automotive use, though. Adapting one from an automotive supplier or a junkyard (pardon me, "donor") part is probably a better idea. You could also use a switch and a couple of fixed resistors in the 5-watt range to have a bright-dim-dimmer-off selection.