LED Lighting Upgrades
I run N-gauge Epoch I/II trains on an analog layout. One of the things that has always peeved me is the electric bulb lighting in loks and coaches which varies in intensity with the voltage sent through the rails. Arnold once had a system which sent some power to the lights before allowing the loks to run, thus giving a brighter headlight to a slower train. However, newer loks with Faulhaber motors advise against running the lok on this type of system.
Anyway, a couple of recent analog lok purchases, one Fleischmann and one Trix, came equipped with LED lighting, and they are BRIGHT, even at crawl speeds. The Trix EP 5 (E 52) even has red lights which swap with the white ones depending on the direction of travel.
I would like to convert some of my existing loks to LED lighting. Can anyone recommend sources for parts, and a manual or article which would help me? Has anyone else tried this? Can you simply replace the bulbs with LEDs, or is there more (shudder!) electrical work to be done? Many thanks...
Bill, in general you CAN replace bulbs with LEDs, BUT LEDs also need a current limiting resistor to be added in series, as otherwise you'll just destroy the LED. The size of resistor you need is dependent upon the current rating of the LED (typically 20mA) and the voltage of the supply you are using - as a rough guide yo'll need to wire a 680 Ohm resistor in series with A LED for use on a 12-15v supply... also ensure that the resistor will cope with the current too, so go for 1/2 Watt or 1Watt resistors rather than 1/4 Watt. Easily available LEDs are 2mm,3mm and 5mm, so they can be a bit bulky for N gauge, but if you search around there are also smaller ones (1.2mm I think), but they tend not to be circular in profile... you can also get surface mount LEDs which are smaller still (SMD LEDs) but they are really meant for machine assembly direct onto circuit boards so can be very fiddly to wire up. I don't know about outlets in the US (Do Tandy still exist?) but any electronics mag should give you a bunch of retailers who can supply...also look out for the colour of the LEDs...unless you're modelling NS, the yellow ones are just too yellow, white LEDs have a very cold blue tinge to them-but if you search around you can get "warm" white LEDs that look much better for simulating the light from a conventional bulb.... they're a bit more expensive but they look much more realistic.
Finally Modellbau Mayerhofer have a translucent "paint" that is supposed to change the output of a standard white LED so that it is "warmer"... I haven't tried it but this may be another option.
Thank you very much for the information, Andrew. I'll give it a try, but I'll need some practice with the soldering pencil first, it seems!
As for the garish white light emitted by an LED, I am a plastic modeler primarily, and I have any number of translucent paints to experiment with. I would think a touch of orange would warm up the harsh blue of the white LED.
Some of my Fleischmann and Arnold models have a small metal disk in the circuit which apparently allows the current to flow only in one direction, thus permitting directional lighting. Are these items or something similar available? Are there other ways of wiring for directional lighting?
Thanks again.
Bill, the components you refer to are diodes - A LED is also a diode, so it only works in one direction. You don't need a seperate diode to make a LED directionally controlled. Obviously if you connect the LED the wrong way it won't light... if you do, just swap the terminals and you'll be OK.
With any electronic components it's good practice to use a heatsink so that when you start soldering, the heat from the iron doesn't destroy the component - so grip the lead of the LED between the lens and the point you are soldering to with a pair of pliers - this reduces the heat conducted to the LED.
I've heard of people being able to correct the blue-white effect with an orange highlighter. I think the "warm white" LED's are nothing more than a blue-white LED with an orange plastic lens.
Jurgen
Andrew - I knew the electric component name I was looking for was not transistor, but I forgot about diode! So the LEDs will operate directionally without any special wiring...this may more than offset the hassle of adding a resistor.
Jurgen - There is an orange highlighter sitting right here on my otherwise nearly-empty desk and I never thought of using it to tint headlights! Genius! Thanks for that elegant idea. The color choice is basic color wheel stuff - as the white LEDs are overly blue (harsh), you want to add the opposite of blue (orange) to counterbalance it.
Thanks again, gentlemen...
Hi Bill,
Check out this site from australia.
http://users.speedlink.com.au/~imra/seminar2.html
It has some pretty nifty ideas for loco lighting with LEDs.
Cheers, JC.
In the older Fleischmann , Roco, and Arnold locos you can fit 3mm LED, it's the same diameter as the bulb used.
Try also:
http://www.kpsec.freeuk.com/components/led.htm
http://www.pollensoftware.com/railroad/index.html
And one that will make you thinking : :twisted:
www.hobbyinside.de check Betreibswerk and Werkstatt sections :8)