I'm sorry Ned, I don't know how to explain more clearly, but see if this clarifies. One of the 2 servos flutters/twitches, whatever we want to call it. If I unplug and switch their source plugs, it's still the same one, on the other channel. If I swap servos from any of the ones I have, the problem persists.
These are on a large model Landyacht, but as I said above it was just under test. One channel serves as steering, one as a lever arm sail winch, as suggested by the guy who has built a good number of these, components as suggested and used in almost all of the landyachts. (Not a BAT).
It seems to me that the best solution offered on the videos is a ferrite core, now where do I get a couple, as I have a few models to get working.