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Old 31st May 2008, 11:08
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Foghut Foghut is offline  
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Join Date: Oct 2007
Location: Between a rock and a hard place
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Quote:
Originally Posted by nick View Post
Hi All,

After looking at my graham farish coaches i am contemplating lighting them, although LED bulbs are too bright and gow generate heat.
There's no easy way of dimming LEDs. Fitting a resistor in series to an LED doesn't really work as they're semiconductors and don't follow Ohm's law. You could "daisy chain" them in series with a current limiting resistor to keep it to about 15mA, remembering that there is a voltage drop of 0.7 Volts across each LED.

The simplest soultion might be to put a filter round them or even paint them to reduce the light output. Also Maplin does a wide range of LEDs with different levels of output, so you might find a less bright one.

And why are you worried about short circuits ?

HTH,
Foggy.
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Last edited by Foghut; 31st May 2008 at 11:18.
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