DCS & Legacy on Modular Layout

John,

To muddy the waters for you, is any equipment on the layout other than the one MTH engine? We've had minor issues with a certain MTH engine (and not others) depending upon what is running.

John,  I have been having the same issue and my layout is smaller.  I been checking track connections and wiring. It seems that in the last two weeks there have been a lot of posts concerning this issue. I starting to wonder if it is an issue with the TIU. I replaced mine about two months ago. This one has 4.30. I powered down my TMCC base but still have the issue. Thought I had it resolved but after a day, the issue returned.

Bobby, nothing on the layout but the one MTH locomotive when we do the test.  The only variable is the power applied to the Legacy base.

suzukovich, your problem appears to be slightly different, as soon as we remove power from the Legacy base or disconnect the track wire, the problem is gone.

Is the 9 pin being used to connect the 2 systems?  If so, I seem to recall the original TMCC cable that MTH put out did cause issues when used with the Legacy base.

We don't connect the two systems.  The only connections to the Legacy base are the power and the track wire.

I had a weird issue where I wouldnt get any legacy signal unless I put the Legacy signal wire on the input of the TIU. Every time I look at the TIU's with the legacy signal wire on the input it drives me nuts since this defys my convention but it doesnt work the other way

Have you tried another base, power supply, and DCS system in case one of those components have an issue?

I imagine you probably have but...

Is it possible to plug the legacy base into a completely  different wall outlet circuit?

Does the TMCC base do the same thing? (if you have one)

Matt, our Legacy signal is fine without or without the DCS connected, it's the DCS signal that gets nuked when we power up the Legacy base.

Marty, The same thing has happened with three different Legacy bases. I have not tried an old TMCC base, it's probably worth a shot, though most folks have Legacy CAB2 remotes, so that would be a problem.

I haven't tried the Legacy base on a different outlet, but since the DCS has no direct coupling to the power line or earth ground, I don't have high hopes for that changing things.  I may try that tonight anyway, just to see what happens.  I might also connect the Legacy at the opposite side of the layout as a test, though again I don't see this as a high probability solution.

I've been thinking of adding the 22uh RF choke in series with the Legacy lead to the track to see if that has any effect.  I'm also going to try a series capacitor to see if there is any DC shift or other coupled voltage that might be causing an issue.  These are really a "shot in the dark" to see if I can affect the issue positive or negative.  Finally, I'm thinking of a low-pass filter to damp any 3.27mhz signal while letting the 455khz through on the Legacy track connection.

Hopefully someone from Capitol Cities or Pittsburgh Hi Railers will chime in. I think both of them run DCS and Legacy on their big layouts. There hasn't been enough interest in my club to attempt rewiring for DCS so I can't help here. Its a major challenge though, especially if the layout configuration changes every show.

Pete

I know, but there can be strange things afoot when DCS is involved

Where do you connect the legacy signal at?

Try moving it furthest away from the point where you connect the DCS at. I believe you can add the Legacy signal anywhere right? It worked in two rail anyways. It still affected it, just a little better result.

 I'm going to add it someday when I get the patience. I thought it was worse in two rail? I will probably just have it on it's own tracks.

I wish the archives went back further... If I remember correctly this issue came up when legacy first came out.   Don't rule out a different wall outlet just yet. (I know you haven't)

I'm going to try all of those, I'd like to get this working and understand why it doesn't work.  I'm calculating some low pass filters now for that test.

Hi John!

I run both DCS and Legacy on my layout, run trains under both control systems simultaneously, and have never had any issues. I have no clue as to what the DCS signal strength is, but the DCS locos run fine.

I get the occasional 'Engine not on Track' and similar messages when I have not run a DCS engine for a while, but have always been able to resolve the issue promptly. At worse, I have deleted and re-added the problem loco. But again, this happens infrequently. Once the locoes are recognized, they run fine. 

Legacy locos, on the other hand, NEVER fail to run fine 100% of the time. 

I have two TIU's connected to eight relay distribution modules, connected to 48 districts and tracks blocks. The Legacy base is connected with its one wire to the outside rail. My layout has over 900 feet of track and 57 turnouts.

Good luck!

Alex

PS. I had one issue with the Legacy early on. Some Legacy locos were not responsive in one stretch of about six feet of track where the second level was right over it. I solved this by adding a ground wire between the upper and lower levels. The ground wire is connected directly an outlet ground. Funny thing is that I have about 200 feet of track in the lower level under the upper level track, but only six feet had a problem.

It's a mystery Alex, the Legacy kills the DCS track signal dead!  I hope I can chase it down, I'm sick of not being able to run both on the club layout at the same time.

Have you tried isolating sections of the layout to see if there is an oddity in a module causing an issue?

When we were resolving the DCS issues, we worked our way around the layout sorting out signal issues as we went.  Now that were done with that process, I get 9's and 10's all around the whole setup on both tracks.  This is a bus wired setup as is pretty mandatory with a modular layout.  The only thing we do is connect the Legacy and the DCS goes in the tank.  I suppose anything's possible, but I really think trying to attack it that way is probably a very low percentage play.

It was just a thought beings you have tried a lot of other things.  The problem maybe easier to isolate on a smaller section of a layout than large.