A DA-SR board will pretty much fit in the space available on the GP15-1. Tape the underside, so it won't short on the weight. Solder the wires to it. Newer DA-SRs have resistors on the board, and cutting a trace will put them in play. Walthers or other LEDs can then be hooked up with no other wiring. The resistors are on all 6 functions. I have one partially installed. I tried putting some old Kato trucks under it, but it threw a driveshaft.
Mike WSOR engineer | HO scale since 1988 | Visit our club www.WCGandyDancers.com
I put the exact same decoder in a couple of Walthers GP15s, and I didn't have to do any motor isolation. I would think you should be okay, though as David said occasionally the factory will make a mistake. I just cut out the existing circuit board, and installed the decoder in its place with the proper wires going to the proper leads on the decoder. It's easy to trace the wires back to their source as either pick up wires from the trucks or motor leads.
Since I tore out the original circuit boards and lights, I can't help you on whether or not you'll need a resistor. I'm actually considering putting the board back in though, as I haven't found a better way to do headlights yet. I was actually wondering too if I'll need a resistor or not.
Noah
Anything I need to know about installing a NCE D13SRJ on a older Walthers GP15?
-do I need to isolate the motor?
-are the bulbs OK or do I need to put in a resistor? If yes what type?
Thanks for your help!
S. Crabtree
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