What's the Difference?

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Larry

Larry

Long Winded Old Fart
between a regular LED & a Defused LED? I wanted to order some 12V. LED's from a company & it says defused, is that a difference in the forward brightness?:confused:
 
a diffused LED has a matte surface so that the entire surface glows with a more uniform color. Imagine taking a clear light bulb and going over the surface with a bit of sandpaper.

A regular LED has a smooth, shiny surface. It makes the actual glowing part glow brighter than the plastic surrounding it, and the brightness can vary depending on the angle at which you view it. It can be harder to see at some angles.
 
diffused on the left
(not my picture)

personally i always got water clear ones till now. then i would just skuff them with water paper to make them matte if needed.


How-to-Diffuse-an-LED.jpg
 
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For headlights, I personally use clear LEDs. They're focused like the real thing, so they are much brighter when you're looking at them head on.

If your LED shines through some clear plastic in the headlight, more of the light will get to the clear plastic, and the plastic lens will do some diffusing for you.

JohnP
 
There were some at http://www.sciplus.com/search.cfm/scategory/LED/term/led/srch.fp/1. The white one is too big for most uses at 8mm but the LED's by the dozen are a pretty good price if you want green, orange, or yellow. You can also change the color by using Tamyia transparent paint, except to white, of coure.

Larry, diffused LED's are good for area lighting, like buildings. You want the focused LED for headlights, since all the light is directed forward and very little escapes out of the sides.
 
Thanks Everyone for answering my question. The place I was going to order from was;
AllElectronics.com. They have excellent prices for LED's & Resisitors as well.
I'm still shopping around for a good price on 12V. DC LED's w/a built-in Resistor.
This summer I'm installing LED's in all my engines for headlites & some roof mounted flashing yellow LED's. I have been experimenting w/some LED's I bought off of EBay w/seperate resisitors. I found that the 3mm's were better than the 5's. I also bought 100-560K resisitors for $3.95 w/free shipping. To use them w/my LED's I have now I have to use 2 resisitors soldered together. using 12v. LED's would be a lot easier to install.
 


Larry said:
Thanks Everyone for answering my question. The place I was going to order from was;
AllElectronics.com. They have excellent prices for LED's & Resisitors as well.
I'm still shopping around for a good price on 12V. DC LED's w/a built-in Resistor.
This summer I'm installing LED's in all my engines for headlites & some roof mounted flashing yellow LED's. I have been experimenting w/some LED's I bought off of EBay w/seperate resisitors. I found that the 3mm's were better than the 5's. I also bought 100-560K resisitors for $3.95 w/free shipping. To use them w/my LED's I have now I have to use 2 resisitors soldered together. using 12v. LED's would be a lot easier to install.
Click to expand...

Larry a great find! I was checking out this site you posted very intersting indeed! Good prices!

If Jerome or Mark is reading this I wonder where Mark gets his LEDS?
 
I found this web site. has a lot of info on LED's. Check it out. I printed out a color wheel for resisitors.
kpsec.freeuk.com
 
with some creativity, you can shape an LED with a dremel or sharp knife. As long as you don't disturb the actual diode at the base, many shapes can be made with the plastic that surrounds it. Years ago I made one into a cab-roof strobe and painted the base silver to represent the metal base.
 
no need for dremel, the usual file shapes it into desired form in couple passes.
as for the price i don't think walgreens or menards can be beat - 5$ for 50 LED string of Christmas lights
 
Anton, I beat that price last year. I got 60 LED Christmas tree lites for a $1.50. The voltage comes out to 1.7 DC volts ea.
But, to use them for headlites on an engine the 12v. LED's w/a built-in resisitor is a lot easier to mount I would think. That's why I've been looking for a clear one w/a 20 to 30 degree lens. I've contacted 3 diff. companies to see if they have anything. I can get the defused one's for 30 cents ea. in a 100 pack, but that's not what I need. I have 3mm & 5mm ones now that I have to use a 1K resistor & those were $16.95 for 10 of each plus freight. I have 180 of the 5mm Chrismas lites, but a 3mm works a lot better.
 
Has anyone ever bought anything from China thru EBay? I can get free shipping for 100 clear 12v. DC LED's w/a 20 degree for $19.45. But, has anyone ever had problems?
 
well that is a great price :)
i don't think leds come with built in resistors (thanks goodness)

i ordered plenty of times from Chinese sellers. always recieved the items in 7-14 days.
the only problem i had is with those dual color leds. ordered green/red and got blue/red instead.

i have plenty of 5mm cold white and 3mm warm white (which i got for the engine lights), if you concerned i can share some.
 
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I've found plenty of them w/built in resisitors, just not clear. I plan on adding a small resistor if needed just in case.
How are the cold & warm white for headlites?
 
I get most of my LEDs from Ebay and find dealers from Hong Kong have good deals. What you want is the Golden White LEDS for headlights in either 3mm or 5mm type. Then I have turned many LEDs down on a lathe for different locos as shown below.

S4LED2.png


S4Cab1.png


S4Cab2.png


DSC00669.png


DSC00675.png


SW1LED.png


WalthersSW1CabHLC.png


WalthersSW1FrontHLB.png


WalthersSW1A.png


WalthersSW1B.png
 
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Thanks Mark for the answers to many of my questions. I just ordered 100 from China. I was going to do the same thing you did w/yours. Cut them down to fit where needed.
I've been reading a lot of stuff about LED's in the past week or so. My next project will be installing roof beacons after I study that item. I want to do a lot of electronics this summer & will be asking many questions. NO DCC in my future. Ditch lites & reverse lites in each loco is my ultimate goal. Got 65 engines now. Few Steam engines in the roster in the past 30 days. the steam engines already have great lighting. mark, thanks for the great pics.
 
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