LED Sizes

[Anonymous]

Greetings,

I was curious on what size of LED I could use to light up a HO signal.

I looked on Radio Shack website and saw 5mm red/green ones.

Would this be the right size for a HO signal?

Thanks,

Mark in Texas

[nfmisso]

Mark;

It depends on the signal, and where you are locating the LED. 5mm is over 17" in HO.

There are many smaller LEDs available, at much more reasonable prices than RS if you are buying more than a couple. See:
http://www.allelectronics.com/cgi-bin/category.cgi?category=340&type=store
http://www.digikey.com/

[orsonroy]

In general, you'll want to look for T1 sized LEDs. If you're willing to shell out a few more dollars per LED, there are specially shaped LEDs for specific uses, which are listed in the Digikey website (I actually suggest ordering a paper catalog, since the selection of LEDs is HUGE). If you're a good solderer, various surface mount (SMT) LEDs would also work well, especially 0805 and 1206 packages. Digikey also sells a series of PC board panel mount LEDs from Chicago Miniature Lamp that come in their own plastic housings. I've got several twin and triple LED housings, with LEDs installed, that I plan on turning into signal heads, with a bit of trimming and Oregon Rail Supply shields and masts.

[Eriediamond]

I didn't post this, but thanks Nigal and orsonroy. Question- after checking out the sites ya'll posted, what is the difference between a regular LED and one that is listed as "point source" I believe they said??

[cacole]

A diffused LED gives off light similar to a frosted light bulb; i.e., the entire LED surface seems to emit light. A point source LED is visible only from the front and not from the sides. It's worth mentioning, too, that LEDs now come in many different colors, intensities, and sizes; even with flashing circuitry built in. There are jumbo 8mm LEDs, standard 5mm LEDs, 3mm LEDs, and surface mount LEDs that get so small you need a magnifier to see them. I use these as marker lights on a caboose. There are even LEDs that cycle through the various colors of blue, green, red, white, pink, and yellow; and ultra-bright LEDs that hurt your eyes if you look directly at them. These ultra-bright white LEDs are good for use in switching yard light towers and other places to replace incandescent bulbs.

[michealfarley]

Check out Demar Electronics.....

www.demarelectronics.com

LED's as small as 1.6mm, which would be in the 6" area in HO scale. Very friendly, speedy service, and the LED's themselves have good, bright light.

[Anonymous]

Greetings,

Thanks for all the info. I want to use them for a HO Model Power signal bridge.

Mark in Texas