# advice needed



## buck71usa (Dec 27, 2011)

I found in my collection a nice A-B unit i wanna add a basic decoder to. Both are athrean open frame units. The B unit is straight forward. The A unit is the one im unsure about. The A unit has metal trucks with the light built into the trucks so it has me a lil perplexed as to how to wire it. Im hoping someone with more knowledge than i have will be able to help. Heres some pics to see what im talking about.








The metal trucks.


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## Brakeman Jake (Mar 8, 2009)

I assume you have installed decoders before so will stick to the lamp install.If I were you,I'd simply remove the actual bulb...that'll give you some space and I'd insert a LED inside a small length of plastic tube glued to the inside of the shell.Then you could power the LED (with a resistor) off the decoder's white and blue wires.

I believe you're aware that the frame is "live" on these and that you'll have to isolate the motor carefully.


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## rrgrassi (May 3, 2012)

Use a multi meter with the continuity setting so you can see the circuit. I have the Athearn U30C with the metal truck frames, and it has a digitrax DCC chip in it. The lights were changed out to LED. 

Like Brakeman said, those metal frames are live.

Due to the current draw of the old motor, I ended up remotoring. 

I also have the PA and PB set with the metal truck frames. The PA has LED lighting, and both were re motored. They were a pain because they needed to be milled out. I broke many a dremel cut off wheels. But it is done and they are now waiting for DCC and repainting. They are the PRR type that prototypically had a singe head light and single air horn.


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## Southern (Nov 17, 2008)

You could leave the light there and have it on all of the time. I do not know your layout so that might be a bad idea.


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## buck71usa (Dec 27, 2011)

Thanks all for the advice. After doing some digging I have found a pair of plastic trucks that will fit and stop any possible headache. I do like the idea of the Led. Thanks for that.


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