Thanks for the responses. Unfortunately, my first two posts aleady answer all of the questions or diagnoses in RJR's and every subsequent response, including: (a) the issue happens everywhere and anywhere on the layout (more detail in my first 2 posts), so "tether angle" is sort of irrelevant given the issue happens randomly on straightaways, curves to the left and right; (b) a power drop is not likely, as every other locomotive - even all my MTH diesels - do not experience the issue, not to mention my consistent 18+ volt multimeter readings throughout (confirmed even by these same steamers' electrical power readings); (c) not the black on the center rail given I already said that signal strength is 10 throughout; and (d) well, I think it's obvious from the list of locomotives I provided that every one of them had a trailing truck, given the smallest wheel arrangement stated in 4-8-2.
RJR - good question about a conventional test! I have a Polar Express conventional locomotive and ran it around the tracks repeatedly - it does not experience this issue when run around the track at any speed.
I'm far from an expert in this stuff, but I'm wondering if it has something to do with the wheels on these things not being firmly to spec (as measured by my O scale NMRA metal measuring device thingy) and this variance causing electrical gaps as these things chug down the track?
Thanks
Peter
