Trying to Decide Whether To Upgrade TIU's or Not?

Art, I am not an electrical guru but would going to the newer TIU's having a stronger signal elimate the problem through the switches. I still have my older, first issued, TIU's and have had no problems. But I did have them upgraded a few years back. Of course my layout is no where as large as yours. Also which probably makes difference for me is I use Gar Graves track with Ross switches............Paul

It seems like selling off the old ones, makes this not so big of a decision. I would keep some of them if possible for smaller jobs like inside yards or at the workbench. How many TIUs would you need just for your mainlines?

 I removed my bulbs and filters from my original mainlines and got stronger signal with the L version. Coupled with newest PS3 boards, they seemed even better. It's the different software versions that have bitten me. It's getting better finally. It was a long frustrating time.

 I still need to look over my outside layout fully and see what happened that the signal degraded with large consists. When tested, I get good signal results. Large consists act up and I didn't know why. I am left at guessing that it was a combination of software glitches and power draw issues. I believe that running a few PS2 engines inside of a large consist with PS3 engines, causes conflicts with response to the older remote. Inside, I had issues too. The software seemed to mess up a couple of PS2 engines that had weaknesses. One got scrambled, 2 got lost. Even a couple of brand new PS3 engines got scrambled so I knew where to look and what to not include.

 I had issues inside and out so that made me look at the hardware first, then the software. Sorry for the long story. Another point is that I still have older TIUs in use today, and they work fine once the software was corrected, or work arounds were established. So I like the L version better. I just think that many issues are not the fault of using an older TIU. Using the newest, just makes troubleshooting easier and less often.

If your TIUs are NOT "Rev L", then all the software up-grading in the world will probably NOT cure your issues. Changing out all your TIUs to "Rev L" versions will make a significant improvement.

Art IIRC there was a thread on here somewhere with "L" TIU's and some issues. Someone may remember it better.

Have a friend who had a first generation TIU I gave him years ago and it worked fine until recently because he never placed fuses in the lines and all his derailments finally caught up with him. He had better signal strength and operations than we do with the L. He replaced it this summer with another older used one and never gets the dreaded "Engine Not Found" message. I'd say in many cases it is just sheer luck with your layout and wiring choices. Let us know your decision and results.

The Rev. L TIU is not a panacea, there have been many issues with them losing the DCS drivers to voltage transients.  I believe the NJ-HR club went so far as to get rid of the Rev. L TIU's and go back to earlier releases.

We have also been having ongoing discussions about both transient protection and also improving the DCS signal drive of the Rev. L TIU, a number of things are being tried as you read.

Other than the 2003 hardware hardening of the Rev Gs, I have had no problems with Rev G or Rev H.  Rev L has been more troublesome.  I have one that is unrepairable---was costing too much to keep working.  The other seems to be working ok, but there are forum threads, to which the Gunrunner refers, that address Rev L issues.  Hisa opening words should be considered:  Rev L is not a panacea.

My layout is about 35'x16.  When a Rev L is down, I pop in an ancient Rev G and see no difference whatsoever, even when using the WIU.

I have two very old Atlas switches on may layout.  I replaced the motors with DZ1000s.  They work fine.  But even the original motors should not affect DCS signal IF you completely isolate them from the track.

My comment about my Atlas switches may have been misleading.  The old switches had small wires for continuity and many switches would not pass the current through the switch.  So we had to add wires on both sides of every switch to correct this.  The way that we added some of the wires created problems with the DCS signal.  So we went back and just added jumper wires to power both sides of the switch.  Some this corrected the signal problem and some it didn't.  

We have reached the point where it has been recommended that we buy all new TIU's that have a stronger signal.  And I might as well get the three WIFI modules to go with it so we can all use phones or tablets during operating sessions.  I'm not sure what REV version I presently have but will check.  I do know that the software is the latest version and all on are the same version.  I replaced two of my TIU's a few years ago, probably before REV L.

I must confess that after having bought 5 TIU's already, buying three more doesn't make me very happy.  But, my scenery is coming along very well and I just want all my MTH engines to run good everywhere on the layout like my Lionel engines do.  

Art

Well before I get blasted, I'll try again.

 I just think you need to solve the Atlas switch issue. I would suggest working with just one problem child until the issue is fixed and signal passes correctly. If the stock wires are too thin or burnt, I would suggest actually removing them or defeating them so you don't get a double signal path.

 Trouble here for me is that I run Atlas 2 rail switches and don't have DCS issues with them. I do usually try to end my blocks on a switch, so that power (high amps) does not need to pass fully thru. Only one engine or lighted car directly on the switch, draws power thru the switch that way. You could isolate one end of a switch and pass power thru a jumper wire even if the block does not end there, I believe. 

 I don't pull the power of my whole train thru the tiny switch wires and expect them to last. I like to run big consists with lots of engines.

 I mean, what if you order 5 brand new TIUs and the issue still is not resolved? Don't get me wrong here people, I too like the newer version L for it's signal strength. I have 3 or 4 of them. Hopefully a new version with proper protection will be released.

Chugman, I would reject that recommendation to replace TIUs, unless you like to spend money.  Better to find source of the problem.

Questions:  Is your layout composed of toggle switched blocks, or have some other means of cutting out sections?

If you let an engine run around sending track signal strengths, are there areas where it varies?

Do you have only one feed per block between fiber pins?

RJR posted:

Chugman, I would reject that recommendation to replace TIUs, unless you like to spend money.  Better to find source of the problem.

Questions:  Is your layout composed of toggle switched blocks, or have some other means of cutting out sections?  

My sections are isolated by insulated rail joiners and are for power districts only.  We divided up the layout into these sections to balance out the power between the 5 power bricks.

If you let an engine run around sending track signal strengths, are there areas where it varies?

We get less than 10 in some areas, but it not too bad in most places.

Do you have only one feed per block between fiber pins?

I feel that this has been our biggest problem.  As were building the layout when we would run into a dead area on the tracks we would add another power feed to correct it.  This created problems with the DCS signal.  We tried various solutions with filters as we didn't want to face the task of a total rewiring job.  We are now going to use jumpers around some of these switches and remove the extra power drops.

I am getting conflicting advice regarding updating my TIU's.  I do not want to throw my money away, but I am sick of poor performance on an otherwise fun layout.  I want to ballast my tracks on the lower level, but don't want to do it until all these remaining DCS signal issues are resolved.

Thanks for everyone's comments and opinions.  Please keep them coming.

Art

Reason I asked first question is because when I added DCS, I found some large sections had poor signals, but when I switched off all other blocks on that channel, signal came up.  So I turned on blocks one at a time and when turning on a switch for another block caused signal to drop on the first block, I added a light bulb to the other block.  Now all good signals.

I assume you're aware that any cars or locos with constant voltage boards may kill DCS signals in that area.

My personal opinion is that switching to Rev Ls to overcome some as-yet-undiscovered issue is a total waste of dollars.  If you or someone you know has built the TIU tester that was featured in another lengthy thread, you might check your outputs,

Do you have a sufficient number of ground (outside rail) feeds?  Is your power distribution wire 14 gauge or larger?

If the turnouts are powered independently, why does the TIU matter. I may be exposing my ignorance, but the problem might be either the switch motors or the AIU.

Tom McGriel posted:

If the turnouts are powered independently, why does the TIU matter. I may be exposing my ignorance, but the problem might be either the switch motors or the AIU.

I only mentioned the turnouts as they were a major problem that caused signal degradation.  Since power would not continue through the turnouts, we had to add power feeds to both sides so an engine would travel through the turnout.  That created a problem where the signal would travel in a loop and slow down and degrade the strength of the signal.  I may not be explaining this exactly right, but that is the way I understand it.  

So I think that I need to do several things:

First, I need to correct as many of these issues as I can by using jumpers and not additional power feeds.

Second, I need to check my signal strength on the whole layout to determine problem areas.

Third, I may want to replace my TIU's with newer ones that send out stronger signals.

Hopefully then everything will work well enough that I can start ballasting my lower level tracks.

Art

Could be various lighted cars causing DCS signal problems along with some Lionel engines.

I agree with RJR above...using the older TIU's a few bulbs are a must.

Art, before you spend a bunch of money on new TIU's why not call Dave Krabel at MTH and discuss your issues. If there is anyone who can solve your problem it is Dave. You saw him at Trainfest last week. Why not call him in Michigan and talk it through?

Milt

The version L will improve signal where it can. It won't improve power flow thru too small or burnt wiring or switch traces. Asking a switch's internal wires to carry the full current thru is too much for the tiny traces to handle. Extra power drops too each side of the switch (creating blocks) is good if you can cut the power flow somewhere. If not, jumpers to carry the extra current would be good.

https://ogrforum.com/...g-and-atlas-switches

For what it's worth, when  I was having trouble with power flagging through turnouts, Steve Ross suggested I add another ground wire to the switch. I worked perfectly.