Weird TMCC Signal Problem-Need Advice

The paint may have insulated the bridge from a possible ground connection, that's the only thing that makes sense.

I am wondering if the paint perhaps has a tiny amount of metallic powder or some such thing that is now shielding the engine from the ground plane signal?

Whatever, its weird. No other command engines have a problem. But the Hudson works fine in all other areas on the layout, even a couple of areas where other TMCC engines show the flickering headlight phenomenon.

I don't get it.

Rod

Just checking, you sure it's a TMCC signal issue and not loss of power?  The Hudson is flickering?

So, did you connect an earth wire yet?

That will solve it.

As for the why...you jostled track connections and added electric current over head with the light and introduced paint.

What kind of track are you using?  If it has wooden or plastic ties then the outside rails are isolated from the bridge.  If it has metal ties (Lionel tubular) then the paint might be transferring TMCC outside rail signal to the bridge superstructure.  The fix is to run an insulated wire (black so it won't be seen) along the bridge structure above the track and connect that wire to earth ground.

Did you hook up the light on the bridge after painting it?  If the light was not connected before, is connected now and is using power that shares track common then the light wires contain TMCC outside rail signal and could be your problem.  Try disconnecting the light again and see if that fixes the problem.

Bob and others;

Thanks for the replies.

I have not installed the silly looking ridiculoously oversized flashing light; I just made reference to it. So that should not be an issue.

The track is good old fashioned tubular with metal ties.

It sits on cork roadbed, but it is screwed through to the metal bridge base in half a dozen spots, so it will be the same signal as the outside track rails.

I think you are right about adding in insulated ground wire along the bridge with a ground connection. That may solve the issue.

Been thinking though, first I am going to try removing the plastic upper bridge structure (only 4 small screws) and see what happens. That will prove out the paint interference possilbility one way or the other.

Rod

Just for kicks Rod - run in conventional mode (turn off command base) and make sure the problem still happens with the same engine.

If does power issue, if not signal issue...

Jim

Hi Rod,

After reading your description of how the track is screwed to the metal base, I'm thinking that if you now ground the base, that this will kill any TMCC/Legacy signal. Have you tried removing the screws so that the track is not electrically connected to the bridge base? (Assuming that the base is painted and that without the screws there will be no direct metal-to-metal contact.)

Nicole;

Thanks, I agree with your assessment.

I think what Bob meant was to lay a wire alongside the track on the bridge deck, but connected to house ground only; no connection to the bridge deck.

Either way I have not gotten around to trying it out yet.

(I am a charter member of the Procrastinator's Society)

Rod