Make a darker yellow LED signal light

[PED]

I have installed a three signal the red and green LED light but I am am not as happy with the yellow LED light. Trying to see if I can a stronger yellow to show by appliying any kind of wash to apply to the yellow.

Any suggestions on how to make to yellow a stronger yellow color?

[mbinsewi]

I'd do just what your thinking of, painting it.  If it's to light of a yellow, almost a white, paint should help.

I've toned down ditch lights doing that.  They were too "bright blue-ish", ( probably used the wrong color LED) so I gave them a couple layers of flat white, checking the color between layers.

Actually, where I get mine, from Evans Designs, they even suggest it, if your not happy with the color.

Worth a try.

Mike.

 

[j. c.]

you might also try a amber one. check out you know where the bay

[BigDaddy]

Tamiya makes "Clear" and Vallejo makes "Transparent" yellow and orange paints.  I've never used either type, but maybe someone can tell us if they would be useful products for you purpose.

[RR_Mel]

I’m currently dinking around with the same problem.  I bought SMTL-4 RGY tricolor LEDs and to get equal brightness the red takes 2.5 ma, the green takes 4 ma but the yellow takes 10.5 ma.  It’s the internal composition of the LEDs.

 

The yellow take much more current for equal brightness.

 

I do not think that you can improve on the brightness of an LED other than increasing the current.

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[j. c.]

PED

I have installed a three signal the red and green LED light but I am am not as happy with the yellow LED light. Trying to see if I can a stronger yellow to show by appliying any kind of wash to apply to the yellow.

Any suggestions on how to make to yellow a stronger yellow color?

 

on rereading your post are the led bycolored or 3 seperate colored led's ?

 

[tstage]

Use a yellow or orange Sharpie pen - i.e. permanent ink type.  If you don't like the color, you can clean it off with rubbing alcohol.

Tom

[BigDaddy]

j. c.

on rereading your post are the led bycolored or 3 seperate colored led's ? Add Quote to your Post

If so it would be tricolor and no way.

[RR_Mel]

The reason I went with the SMTL4 LED is because I tried at least five different bi-color LED batches supposedly from different manufacturers and none of them produced a good Yellow.  The quality is better using a common cathode LED, the common anode are totally worthless.  The SMTL4 is a common anode.

 

 

 

Edit:

 

The SMTL4 is a three LED package, three LEDs inside one package requiring 4 wires.  One common positive and seperate red green and yellow.  You size the current with a resstor in the red, green and yellow leads.  I use 5 volts from an Arduino MEGA.  I have a 1KΩ resistor in series with the red for 2.5ma, I have a 220Ω resistor in series with the yellow for 10.5 ma and a 560Ω resistor inseries with the green for 4.2ma.

 

They are very close in brightness.

 

 

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

 

 

[PED]

My LED was three seperate LED's in a three light mast. The red and green looked good but the yellow had a much weaker look to it. I think I may experiment with other yellow colors.

[RR_Mel]

Yellow requires higher current than red and green, lower the resistor value to increase the current.  That will make the yellow LED brighter.  If you have a multimeter measure the current and keep it under 20 ma max.  Try matching the currents that I measured, 2ma for red, 4ma for green and 10ma for yellow.

 

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[j. c.]

PED

My LED was three seperate LED's in a three light mast. The red and green looked good but the yellow had a much weaker look to it. I think I may experiment with other yellow colors.

 

ok if 3 leds  try a amber led.

[RR_Mel]

This morning I tried three individual 3mm LEDs, red, yellow and green with my bench power supply.  Each with a 1KΩ resistor, the finding was the same as the SMTL4 three LED package.

 

By varying the voltage to change the current the Red at 2.4ma, Yellow at 10ma & Green at 4ma all are equal brightness.  Change the current on your yellow LED and it will work fine.  It needs more current.

 

 

EDIT:

 

I tried a 680Ω resistor in series and the yellow LED measures 15ma at 12 volt and is a very bright yellow.  Experiment with resistor values between 680Ω and 1000Ω if you are using 12 volts for your supply voltage.

 

 

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[wvg_ca]

Tamiya make a clear / transparent amber colour ....

it works if the leds are seperate, or even a solid yellow or white [like for ditch lights] .. I use it here for white ditch lights [no signals on my layout]

[NWP SWP]

Perhaps an orange led would work? Just a thought!

[SeeYou190]

BigDaddy

Vallejo makes "Transparent" yellow and orange paints.

.

I have all the Vallejo "Transparent" colors, and they are very close to being fully opaque. They are nice bright colors, but I have no idea why Vallejo calls them transparent.

.

-Kevin

.

[dbduck]

SeeYou190

 

 

BigDaddy

Vallejo makes "Transparent" yellow and orange paints.

 

 

.

I have all the Vallejo "Transparent" colors, and they are very close to being fully opaque. They are nice bright colors, but I have no idea why Vallejo calls them transparent.

.

-Kevin

.

 

 maybe they mean "translucent"?