I need to know what’s better for Locomotive head lights like F7, E7 ,ect. Is it 3mm LED’s with 750 ohm resistors or Simply Grain of wheat bulbs. Which of the 2 is the brightes and which of the 2 burns out the fastest. I had past experiance with GOW but never delt with LED. And are LED more technical to deal with.
LEDs do not burn out, and they do not put off any heat.
Bob Boudreau
Well there I have it. LED’s are it. Do I have the matching resistor correct? 750 ohm with 3mm LED? or should I go with 5mm?
Thanks Bob Boudreau
the white light LED’s are perfect for headlights…on the locomotive models you are refering to, glue the LED against the clear plastic piece of fiber optic lens that come with the locomotive…I did that to an F-7 and it is one of the brighest and best looking lights i have on any of my locomotives…you can run a resistor in the 350-700 ohm range which will work just fine …chuck
[#ditto] LED’s are the way to go. The whites and the golden yellows are nice too, for older style lights.
I use 3 or 5 mm LEDs for headlights, generally with 1K resistors. I’m running with DCC, by the way. Besides the low heat and long life, LEDs also draw very little power. The light thrown by a LED is very directional, which makes them even more desireable as a headlight. (However, it makes them less nice for the lights inside structures.)
LEDs these days are coming in slightly different colors, too. I like the “Golden White” LEDs which have a nice yellowish glow, and look much more like real headlights, especially from the 1960’s where I model.
Thank you all. I’m going to get some. 1 more thing. Can the yellow Flashing LED’s be used for Beacons?
Well given the choice of those two, it is no contest - LEDs. That is assuming you select the proper color adjusted ones. However, I quit using grain of wheat bulbs years ago. They are way to bulky and produce too much heat. I started using the PFM 1.5v micro-minature bulbs way back in 1983. They cost almost $3 each back then. Fortunately other companies have started making them and the price is way down. I run them at 1.2-1.3V and have not burned one out yet. They produce the right color, are tiny enough to just insert into the headlamp holes without needing the fiber optic. In this way they make their own “lens”. They look great in multiple bulb headlamps (like on F units). And they don’t have the one way power issues that a diode has (see some of last years discussions about them over in the layout form).
Hands down - LED. [tup] The golden-white LEDs on my Stewart Baldwin light up the back wall.
Tom
If all you want the LED beacon to do is to flash on and off, you can use just about any decoder which has a flashing function to control a normal yellow LED to do that.
If you’d like the LED to change intensity as it flashes, the best decoders I’ve found for that are NCE’s SR-series decoders. They have the programming and circuitry to do some pretty sophisticated flashing, ramping the intensity up and back down again, rather than just turning the LED on and off repeatedly.
Are LED’s easy to wire to a NCE decoder?
All you need are the blue and white wires for your front headlight; yellow and blue for you rear headlight. (The blue wire is your common.)
You do want to make sure that the blue wire goes on the correct side of the LED (can’t remember which right off hand) and that you have a 1K resistor inline. Black heat shrink around the head of the LED will help concentrate the light through the lens.
Tom
Where can I find reference material on adding LEDs or LEDs/fibre optics to N Scale locomotives? (I have a couple of older models without lights).
At present I am running DC. Do I have to convert to DCC and then add LEDs/fibre optics at that point or is there a way of doing it to a DC loco??