Signal Strength around Portable Layout

Brandy,

the "outer loop signal strength was 3-4" (pins in here).

If you have multiple drops from the TIU to the track without any blocks (made by remove ing center rail pins between drops), you're asking for trouble.

leave all of the center pins out of 1 loop around the layout. We did on the inner main...That this would enhance the signal strength.

That should improve things on that loop.

If your TIU is older than the current Rev. L, placing an 18 volt bulb across the output of each TIU channel in use should also serve to improve things.

1st I want to thank you Barry, for giving me an answer!

1) outer loop has all pins installed, + Daisey chained from module to module.

Outer loop has the low signal. We ran out of Club time, and didn't check the inner loop.

2) Inner Loop: all sections have the center pin removed around all 16 modules. Power comes from the tiu to the track, then the Daisey chain wiring between modules, is carrying the power. (No center pins)

**I'll have to check out the inner loop this coming Monday Morn, as we ran out of time, and didn't get to check it.

3) Our Tiu has been upgraded from a local MTH/Lionel service dealer. We also had him to do a recheck to make sure something hadn't gone awry in the "Tiu".

Seems like there is a Sh*t load of Voodoo in the MTH electronics,  that we don't experience with TMCC, but the "New Breed" in our Club likes MTH, and that's Ok.  You know the old sayin "It Youth to make Change".

Once again I appreciate your help, + I want to try one check fix at a time, so we can find what is causing the problem.................................Brandy!

The rev L TIU is a hardware revision that a tech cannot do.  He most likely did a software upgrade.  Check the bottom of the TIU,  If it doesn't say "Rev L" do as Barry says with the "magic light bulb trick."  It will help (at least a little and maybe more.) 

What gauge is your buss wire system, and are you running a common ground or individual grounds for each loop?

Forgot to mention, the only ground we have is what is coming thru bld electrical circuits, that we connect the transformers to, basically grounded thru the 3 prong plug @ the wall!

Brandy, this Filter for MTH-Controlled (DCS) Model Train Layouts has solved the signal strength on several modular layouts.

IMO, 16 AWG is too small for a modular layout. If you're running multiple tracks through a single common return (especially if that is also 16 AWG), thats likely most of your problem. Its not like a home layout where 16 gauge wire is OK, all the buss connections add resistance to the line. We (the National Capital Trackers), just dumped our old harness for a new one thats all 12AWG and each loop has its own common return. The only place the commons tie together is the TIU outputs via the TMCC/Legacy connection. Since we've switched, we've gone from signal issues all over the place to virtually no response issues. I believe our TIUs are Rev I, and we've been able to take out all the filters and still have no issues, although through some experimentation, have found that breaking the layout at the point farthest from the transformer inputs and installing Deats filters does provide an even better result. 

Barry,Boilermaker,Chris,and Susan, Ou Club and I, want to thank you folks for taking the time, giving us some good info to work with.

Chris, I checked our Tiu yesterday, and it was model "REV b13". I called our local Lionel/MTH Technician, and he said he was sure ours was 1st gen Tiu. I also told him of our problems, he said that he had to call MTH today, and would tell them of our scenerio, and see what MTH would advise. He did say he thought our Tiu would have to be changed out, and also the "Deats" treatment would have to be done. He said that he also thought our "Daisy Chaining" and track pins between the modules would have to be addressed, as well.

Once again folks thanks for your help, wished I was smart enough to add a drawing to my posts. I've gotten to the age, I like watching the movie enlieu of reading the book. If any of you are like that, you have gotten old!....................Brandy

Brandy,

REV b13... and he said he was sure ours was 1st gen Tiu

Your tech is mistaken.

First, there is no such TIU model. What you most likely have is a Rev. I3.

Second, this is not an original model TIU and is only one generation or so (plus a couple of minor mods) older than the current Rev. L.

If it's operating correctly, there's no real need to replace it.