Large Scale Central

I want to convert a GP30 to be battery and track powered, how?

Glad you got it figured out. Assuming it was one of those two pin JST connectors that messed you up…


There does not seem to be a standard as to which pin gets the red wire. I’ve purchased them wired both ways. Of you have patience, the pins can be released from the plastic housing so you can correct the polarity. Or, just cross wire them and be done!

For the sound, if you power the board from the battery at all times, it will idle for an extended (very long) time when running track power and the engine is stopped. In order for the speed to follow, the speed input needs to be connected to the output of your Revo or the track depending on switch position. I believe my diagram near the top of this thread shows how that is done.

BTW - If you need a source for these, Ric Isard is still in business and sells them in bundles with silicone insulated wire (very pliable) for a good price. He now does business as and sells through Facebook Groups. I have no idea why he doesn’t post here. I guess he’s afraid of feedback from dropping his RC line.

Yes I have those connectors. I created a wire setup to plug into the truck pickups to the switches and then back to the motors through the USAT board. I checked everything for continuity, thinking one of my solder spots was bad, nope. I checked the switch thinking I might have put too much heat to it, nope. I then powered each motor independently through my setup and they worked. It wasn’t until I tried both together the backwards factory plug was found.

Right now I have a pigtail off the power return to the motors connected to the sound card. I just tested it on the battery Revo side of things and it works. I should test it with the track power just to be sure but there is no reason that it will not work with that.

It would be slick to have the phoenix use the main battery as a back up battery in both the Revo and track power modes.

Great news. The GP30 is Alive and it was tested out in the main yard today. Next up is to add some ditch lights and get painting the shell.

It was a long process but the GP30 is just about done. The electronics gave me some fits and then the paint had a reaction that was to bad to repair so into the dip tank the shell went but here we are finally on the track.

I still have to install the side railings and might add a bit of weathering but I’m very pleased with how this turned out and it might just be my new favorite engine. Thanks to all who helped along the way.

Are you making some housings for the ditch lights???

No housing. I drilled a hole, poked it with a silver sharpie and hot glued the lights in from behind.

Here is a video that might help, I would also consider changing all the lights to LED’s, plus adding ditch light, etc. Rail Pro offers so many features to add them just makes your engine so much more lifelike. LED’S use less drain on the battery over the standard factory lights and the cost is so little, it becomes a no brainer.

I thought all the bulbs in the GP30 were already LED’s ?
Railpro is slick but I already had the Revo and battery earmarked for this engine.
It is done now so once the weather improves this GP will be going to work on the RR.

I personally do not know which engines have LED’s, or the old style bulbs. This is something you would have to look at your engine and go from there. I was using 40 year old LGB engines which did not have LED’s. I would think that newer engines do have LED’s today, but their older models probably do not, but who knows.