Agreed. If dimming isn't necessary I'd try a white LED and add a series
resistor to get the desired brightness.
Thusly spake Steven Trovato:
> Yes, yes. I was really thinking you would just compare the resistance
> of the known bulb with the resistance of the candidate bulb. The V=IR
> part was a not very well thought out afterthought. Sorry. In any
> event, I think we're overanalyzing this whole thing. There are little
> bulbs out there of appropriate voltage. Try some and find one that
> looks like it's the right brightness. Done.
> At 04:56 PM 2/25/2008, Pat Horne wrote:
>> Cold resistance of a bulb is much lower than hot resistance. That's
>> why most bulbs burn out when you turn them on.
>> While it may not have an exact correlation, I just measured the cold
>> resistance of a 130V 75W bulb and it measured 21 ohms. That would be
>> 804 Watts cold filament dissipation. Using Ohms law, the resistance
>> of a 130V 75W lamp will be 225 ohms hot, so you might be able to
>> measure the resistance of another lamp and multiply the resistance by
>> 10 to get hot resistance, but my measurements is just a sample of
>> one. YMMV.
Pat Horne, Owner, Horne Systems
(512) 797-7501 Voice 5026 FM 2001
Pat@HorneSystemsTx.com Lockhart, TX 78644-4443
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