Decided to try to convert an MTH Premier full length vista dome to LED lighting. I have previously converted two Sunset brass passenger cars with one of Roy’s units, and had a third kit for a vista dome, but decided for this one, try out a previously bought buck converter with bridge rectifier and golden white LED strips.
And of course it is sort of a puzzle. I decided to try to make the MTH circuit board landing pads be at 12VDC and wire track voltage directly to the AC input of the converter, and have a separate regulator for each level, tucked in at the ends.
Install LEDs, wire it up, put it on the track, pull it around, and it blinks. My brains says it has to be those landing pads, clean up the springs. Nope. Bypassed the pads by pulling the wires out of the sockets and tightening under screws, nope. Clean the track. NOPE. Then I could hear a slight popping sound. Electrolytic capacitors about to explode? It was at least five years that I bought the boards. Then I finally saw it….
These trucks do not have wipers on the truck axles. The axles sit in a bronze pocket in the lower arms. The ground connection to the lights is connected to the upper arm of the truck, and apparently not a good electrical connection between the lower and upper arms. I took them apart, did some filing to remove paint, and the problem went away.
Note #1: It is not easy to put the trucks back together.
Note #2: I broke the plastic ribs of the vista dome by tapping too hard on the top to knock something off the window.
