grain of wheat vs led

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ChrisQ
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grain of wheat vs led

Post by ChrisQ »

I am embarking on my fiber optic DS9 model. It comes with "grain of wheat" bulbs. It seems I should use LEDs with resistors instead due to the lifespan of the bulbs (plus the heat).

Am I missing something?
en'til Zog
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Post by en'til Zog »

NEVER use Grain 'O Wheat bulbs when you can sanely use LEDs.

Or "Grain 'O HEAT" bulbs to be precise.

GoW bulbs burn out easily, and often.

On the other hand, I have sitting on my computer some LED displqays that have been ON and blinking for 35 YEARS straight so far. And LED life ratings are not to "burn out" they are to the "half of original brilliance" point.

This is for LEDs operated at their proper voltage and amperage.
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ChrisQ
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Post by ChrisQ »

Very good!
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tetsujin
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Post by tetsujin »

en'til Zog wrote:NEVER use Grain 'O Wheat bulbs when you can sanely use LEDs.
And I'd add that you can always use LEDs. LEDs can go places small incandescent bulbs can't, in fact.

White LEDs used to be very expensive - these days they're quite cheap. The color quality has improved quite a lot as well, the so-called "warm white LEDs" are a lot more common than they once were.

(The color quality issue has to do with how white LEDs work. They are, in fact, blue LEDs, but the lens is treated with phosphorescent material which shifts some of the colors to longer wavelengths, producing enough light in other areas of the spectrum to appear "white". Poor-quality white LEDs, like the kind that are typically in Christmas lights, will appear bluish because not enough of the light is being translated by the phosphorescent material.)

Driving LEDs is a bit of an issue as well - incandescent bulbs behave a lot like resistors, the relationship between voltage and current is pretty much linear. But LEDs are much more sensitive to minor changes in voltage - so it's more important to be careful about how much current goes through that LED. Resistors work but for optimal output and reliability you'll want some form of regulated supply...
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ChrisQ
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Post by ChrisQ »

Thanks. I recently bought a hundred pack of 3mm warm white LEDs and also packs of different resistors off of Ebay a while back so I'm ready. However, I do intend to test the gow bulbs against the leds to make sure the brightness is comparable. Those leds aren't very bright and if they are not acceptable I will look at some clear whites. Even the 1.8mm's I have used are much brighter than the warm whites.
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southwestforests
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Post by southwestforests »

en'til Zog wrote:Or "Grain 'O HEAT" bulbs to be precise.
GoW bulbs burn out easily, and often.
Which is why model train manufacturers are shifting to LED for headlights and other lighting.
Especially with the better and better warm white light colors.
"There are a thousand things that can happen when you go light a rocket engine, and only one of them is good."
Tom Mueller of SpaceX, in Air and Space, Jan. 2011
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