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Posted: Sat Jan 15, 2005 2:12 am
by Mats
A PWM signal to the bulbs would seriously shorten the life of the bulb. The bulbs doesn't like to get a varying current, that is why I even have the bulbs wired to not be turned on when I crank the car (current will be "dirty" because of the load from the starter).
Looks very modern when the lights come on when the engine fires. :)

Posted: Sat Jan 15, 2005 9:47 am
by Jim K
I don't know Mats, the incandescent characteristics of filament bulbs will not behave like an 'on/off' load I think, but will see a much smoother voltage than what will show up on a scope. I don't have any data on bulb life when used with PWM supply. It all comes down to what your pocket can term reasonable cost for replacing bulbs vs the ability to regulate light output
Jim K.

Posted: Sat Jan 15, 2005 10:55 am
by DaveH
Guys, a PWM circuit is not necessarily a choppy waveform. The correct size capacitor in parallel with the output can smooth out the waveform. PWM circuits will often incorporate this, sometimes with inductors in series.

I'm not sure, but voltage dividers prob use such circuids. Allied Electronics (US), Radionics or Farnell in the UK will stock such items. Or you could just go with a basic resistor network voltage divider, like Mats mentioned.

Posted: Sat Jan 15, 2005 8:49 pm
by MerrilGordon
Well it sounds like the quad headlight arrangement is not such a good idea as MD reports. Did you have the same problem with oncoming traffic Mats ?

Thanks,
Merril

Posted: Sat Jan 15, 2005 10:02 pm
by MerrilGordon
Clarification; I ment quad low beams.

Merril

Posted: Mon Dec 18, 2006 2:28 pm
by jrreeve
Just installed an adjustable voltage regulator(Transpo)...that was fun!!! Now anyone know which way to turn the screw to turn it up. Don't like getting burned by the exhaust manifold everytime I try and reach down there. Would rather know before I start turning the wrong way! Thanks in advance!

Rob