Posted by David Sherman on Wednesday, December 13, 2006 at 18:41:59 :
In Reply to: Re: Illegal in Nebraska posted by Dana on Wednesday, December 13, 2006 at 08:11:56 :
I remember a "pod-like" automatic headlight dimmer on the dash of a '67 Chrysler New Yorker my dad almost bought. An automatic headlight dimmer is a bit tricky because it has to not get confused by sunshine, electric signs, street lights, etc. The trick is that responds only to "DC" (steady) light and ignores the "AC" (flucuating at 120 Hz) light from streetlights and signs. I suspect the job may be even trickier nowadays since many electric lights now run off of high-frequency power supplies that might look like "DC" to the detector.