JJ & C RailRoad
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Super bright white LED's! I know that there has been plenty of talk on the internet about the bright white LED's recently but I thought I would put up my own article to describe what I have done and found out about the new LED's so far... Below are a couple of pictures showing what a huge difference these LED's can make over a conventional light bulb or even another "standard" LED. At night we're talking beams of light 10 feet or better!
The Aristo-Craft Lil' Critter in the picture above on the left has the stock out of the box lighting. The picture above on the right is the same engine but with 5mm bright white LED's installed. The conversion on this engine was extremely easy. All I did was, first take the Critter apart and remove the PCB's (printed circuit board) with the stock LED's. Secondly I unsoldered the yellow LED's from the PCB's and soldered the new bright white LED's in their place making sure I had the polarity correct. Third and last was to put the critter back together. A little bit of hot glue was the only other thing needed to re-glue the PCB's into the body of the engine. One of the neat things on the Critter was the fact that the engine already had LED's installed in it. The PCB's that held the LED's already had a current limiting resistor installed so there was no need to build my own circuit. Not every engine you try this conversion on will be set up like this so you must figure out what your going to do before you start changing things around. One of the best places to start your research would be at George Schreyer's most excellent web site, he has a great technical page already set up on how LED's work and whats needed as far as circuits go. If you don't understand how it all works after reading his page, maybe this is not the conversion for you to try on your own. Recruit some help! The next engine I want to show you is clear across the spectrum as far as conversions go. This one is a USA Trains GP-7 and it did not have LED's for headlights. It had good old regular light bulbs, commonly referred to as grain of wheat light bulbs.
Pictured above on the left is the USA Trains GP-7/9 lighting board. You'll note that D1 and D2 are the directional marker lights (Bi-Color LED's) that USA loves to put in their newer models. The two large lights in the center of the board are the number board lights. L4 and L5 are the connections to the original G.O.W. headlights. Note that there are separate connection's for each of the two lights. R1, D5, D6 and D8 make up the directional lighting circuit and lastly in the lower right corner of the board is the power coming in from the main PCB of the engine, they are labeled Red and Bla. When I made the change to allow my bright white lights to work in place of the original G.O.W. bulbs, all that I did was remove the lights/wires at L4 and L5 then solder my LED circuit (above right) into place at L5. I did have one problem I think you should know about. When I first made the circuit above, it didn't work. I got it all made up, soldered together, hot glued back in place, powered it up and blah. Only one LED came on, the other one came on only when I turned the voltage up all the way. My first thought was "what the heck did I mess up?". It took me about an hour and a half to finally figure it out. Along with taking it all apart again... I first figured it was a bad resistor, nope. Then a bad wire, nope. A short!, nope... In the end it turned out to be a bad LED. I couldn't believe it. One of my two LED's was drawing all the voltage in the circuit. Yep, when I measured the voltage drop across the limiting resistor it was fine but when I measured the drop across the first LED, the circuit was down to less than 2 volts. I replaced the offending LED and the circuit worked perfectly. Just keep this in the back of your mind when your playing around with this stuff. Don't just assume that any problem you come across is because of something you did. Check everything! Note: I have been documenting the conversion's of my other engines so it's possible that they can be added to this page. If you would like to see a certain one (or all of them for that matter) added to this article, let me know. I have also received numerous inquiries about the LED's and resistor's used for the conversion's. Due to cost and availability in my area I ended up purchasing a big bag of the LED's from Radio Shack. I bought enough to finish all the engines I currently have and by doing that I got a small quantity discount ($3.14 each). You can only buy them from their web site or by calling the toll free order number. The 5mm LED's are part number 900-7864 and the 3mm LED's are part number 900-7863. Use the calculator below to figure out what value resistor you need in your circuit.
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