# Interesting bi-color LED's



## gunrunnerjohn (Nov 10, 2010)

Here's something I hadn't run across before, a RED/WHITE bi-color LED. It happens that I'm doing a lighting conversion on a loco, and this is the exact thing I needed. I'll have the rear headlight turn red for forward, and the front ditch lights go red for reverse. 

Just though maybe someone else might need something like this too.

Red/White Bi-Color LED

Another possibly useful color set.

Green/White Bi-Color LED

A whole bunch of color combinations, more than normally found on these sites.

Bi-Color LED's Available


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## plandis (Oct 5, 2011)

gunrunnerjohn said:


> Here's something I hadn't run across before, a RED/WHITE bi-color LED. It happens that I'm doing a lighting conversion on a loco, and this is the exact thing I needed. I'll have the rear headlight turn red for forward, and the front ditch lights go red for reverse.
> 
> Just though maybe someone else might need something like this too.
> 
> ...


Ive seen these in multi color arrays as well. (thats how LED displays work) you can get a single LED to give multiple colors!! I bought some simple three color ones (red, yellow, green) - simple hookup. With those CC chips you told me about, my imagination is running!


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## plandis (Oct 5, 2011)

check these out
http://www.pololu.com/catalog/product/1074


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## tjcruiser (Jan 10, 2010)

Neat. I've never seen those before. Note the 3 power leads .... two "hot" (one for each color), and one common ground.

TJ


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## Greg Elmassian (Oct 29, 2011)

Be nice to find in common anode, needed for use on DCC.

I'll search their site... good replacements for the silly Red/Green on USAT diesels.

Greg


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## cabledawg (Nov 30, 2010)

Sean used the Red/White for the rear light on my Thomas upgrade. F3 turns on the white and F4 does the red. Cant have them both on at the same time otherwise you get a dimmed white. Nifty little buggers though


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## gunrunnerjohn (Nov 10, 2010)

The RYG ones I've had for some time, I hadn't run across the Red/White or Green/White ones before, and they happened to be exactly what I needed at the time.  Just got them yesterday, they're perfect!


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## NIMT (Jan 6, 2011)

They do work great, but as Greg pointed out you have to get them with common anode in order to work with DCC as the outputs of the decoders are switched (-) and blue is common(+).


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## gunrunnerjohn (Nov 10, 2010)

I've seen some of the three color ones with common anode, but I didn't see any of the red/white ones with that capability. Oh well, I do TMCC, and a common negative is no problem.


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## T-Man (May 16, 2008)

I researched Target Stores, they stock Halloween lights that use multi colored LEDs. I'll need to take a second look now.


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## gunrunnerjohn (Nov 10, 2010)

Turns out I had a common positive for the TMCC, and it IS a problem, see my other thread on inverting the voltage so I have the correct polarity. Messy, but it works.


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## gunrunnerjohn (Nov 10, 2010)

Well, I retract my recommendation for these bi-color LED's! They're crapping out like flies! It's always the white LED that dies, obviously there's a design flaw somewhere. I changed them out twice in the locomotive, and finally threw up my hands and said ENOUGH!

I don't know what the deal is, they work fine on the bench for a short time, but a couple of them crapped out after sitting in a box for a week, then I went to ring out the wires so I could connect them to the circuit board, and they no longer worked! All that happened in the time when they worked and the time they didn't is the shell sat in a box!

I'm not a happy camper, and I'm redoing the lights on that locomotive to reflect the new reality.


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## kluts (Jan 31, 2012)

Update: Have you found any other Red/White LED's? Got the same issue and don't want to start afresh. However, I'm thinking of shaving a small red LED and setting it side by side with a white one behind the lens. in my case the lens is fairly long depth so the light change to red would not be a telltale problem.


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## NIMT (Jan 6, 2011)

I put a red LED's behind white LED's and it works great. A little epoxy and a piece of shrink wrap and you've got a Bi color LED.


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## tjcruiser (Jan 10, 2010)

NIMT said:


> I put a red LED's behind white LED's and it works great. A little epoxy and a piece of shrink wrap and you've got a Bi color LED.


Sean -- love it! There's something to be said for a little "old school" ingenuity!


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## Dan Pierce (Jan 2, 2012)

There are 3mm and 5mm red/white common anode leds out there.

And common cathode can be used on any system, just tie the resistor to the plus side and ground the resistor/led joint with the opposite or inverted function.

Works great in large scale decoders.


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## gunrunnerjohn (Nov 10, 2010)

Where are those 3mm red/white common anode LED's Dan? I mean specifically.


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## gunrunnerjohn (Nov 10, 2010)

NIMT said:


> I put a red LED's behind white LED's and it works great. A little epoxy and a piece of shrink wrap and you've got a Bi color LED.


I'm going to have to try that and see how it looks, could be a solution.


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## kluts (Jan 31, 2012)

NIMT said:


> I put a red LED's behind white LED's and it works great. A little epoxy and a piece of shrink wrap and you've got a Bi color LED.


Ta DA!! Thank you!


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## NIMT (Jan 6, 2011)

Thank you:worshippy:
Glad I could help someone out!:thumbsup:


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