Paul,
If I don't do the center rail isolation I am taking a big gamble in DCS signal degradation?
That depends upon your definition of "big". 
The odds are good that, at some time, not isolating the center rail will cause issues.
The challenge is, I am re-using Ross switches that were ballasted on my last layout...the ballast is cemented in-between the ties of the switches and its going to be a PITA to remove the ballast and then de-solder the center rail to center rail connectors. I guess I could just leave them as-is and cut center rail gaps in the strait sections.
I try to make my track connections tight, but sometimes there's a gap ~ no more than 1/16". I read over time oils and dirt get into track joints and degrade electrical flow, but I have no idea how long it takes, could be long past I am pushing up daisies.
Paul,
Maybe you can just use diagonal cutting pliers to cut the center rail connectors on your switches without having to unsolder them if that's the way you want to go.
Paul
I would leave those Ross connectors alone, and just cut the center rail on the tracks on either side; like you said.
Or just pull the center rail pin (s) on the route ends. ( not the switch point end ).
Gargraves makes insulating pins. I don't see any reason why you can't use them in a Ross switch to connect to adjoining tracks.
I guess people who use Realtrax or Fastrack, etc., modify those track systems in some way for DCS?
As I lay track around the expansion I will try to test trains via DCS and Legacy for performance.
Paul Kallus posted:I guess people who use Realtrax or Fastrack, etc., modify those track systems in some way for DCS?
As I lay track around the expansion I will try to test trains via DCS and Legacy for performance.
Now you're talking... test as you go..
If you have any spare tiu channels you also may be able to take advantage of them. Each one has a dcs signal generator.
I use Fastrack and just used 1 3/8" sections between blocks. No modification necessary. I had to modify for insulated rails and Gargraves transition across bridges, but not a big deal. 10s everywhere.
Paul,
John H in the above post give you the very best way to make Blocks with FasTrack, Lionel sells 1 3/8" isolated short FT sections, that are absolutely perfect for block separation. You can also make your own if you deem necessary as you build. Use the 12 Track join discipline for setting up your blocks, and when using the long 36" straights, it cuts down on your actual track joins, and you find that not all that many Blocks, actually need to be formed, even on a pretty fair sized layout. Remember what degrades the DCS signal the most is Track Joins, the longer Track lengths you use the bigger the Block sections you can make distance wise, making for less actual Block sections in your over all layout. Further with the better signal that the Rev L transmits, only a few isolated magic lights are now required thru out your entire layout.
PCRR/Dave
You've got plenty of advice both ways now. I will share with you I have a huge layout that circles a basement; including one huge "island" going into the center of my space. I had planned for conventional only and literally circled my entire layout in bus wires. THE DCS SIGNAL BECAME CONFUSED. It was designed so that signal travels out from the TIU and return to the TIU; Hence the recommendation for star wiring.
Yes I know some are lucky and hook it up and it works fine with whatever wiring they had. Others have to rip out and redo everything. I had to rip out and redo about half of my wiring. Good luck to you Sir! What works for one may not work for another.
Even apart from DCS, buss wiring of the hot (center rail) circuit has never been a good choice, unless you are running a single train on a single loop powered by a single transformer handle. The reason is total lack of control of individual locos. If the area controlled by a single handle is broken into blocks, then a large degree of control is attained, permitting operation of several locos. Blocks controlled by toggle switches, usually positioned in a central control panel, permit one to stop one or more trains without affecting others. Thus, an overtaking train can be stopped. Or, a double-throw switch could be used to temporarily power a block from a lower voltage supply, or vis a single throw switch a resistor could be cut into the feed for a block to slow up a train.
None of this is practicable for conventional operation if one feeds power to the center of a layout, and from there sends feeds to separate blocks.
Using a buss for common, with frequent drops to outside rails, presents no issues.
Hello, I just joined this forum and have a problem. I have a large two-level layout that I previously wired in bus fashion, powered by a MRC pure power through a TIU with an attached command base. Power drops every 12 feet or so. The several TMCC engines all worked very well, but the MTH Proto 2 engines were sketchy. So I tore out the bus wiring and replaced it with star wiring ( fine -stranded 14 ga). Now my MTH engines work flawlessly with a solid track signal strength of 10 everywhere, but now the TMCC engines will no longer work, or even address. I have a 20 ga bare wire to earth-ground loop all around, but still no luck. What am I doing wrong?
now the TMCC engines will no longer work, or even address
That's a TMCC issue, not a DCS issue. You'll most likely have better luck getting answers on the TMCC forum.
Hi Barry,
When I plug in to my lower level (still bus wired) the TMCC engines run fine. ???????
When I plug in to my lower level (still bus wired) the TMCC engines run fine. ???????
When you rewired from buss to star, you messed something up as regards wiring the command base to the track. Again, it's not a DCS issue, it's a TMCC issue.
FRBOB,
Barry is right as usual, some place you did something wrong when you installed your TMCC drops with your DCS wiring, if your DCS wiring was done correctly, using the block method. Trace everything back to your TMCC base and start again. Here is something MartyF advised me to do, when 1st added TMCC/ Legacy to my DCS layout. Maybe it will help you also. 1st run your TMCC drop to the opposite outside rail of your DCS TIU Track connections. Then run an additional TMCC drop directly to every out Black Channel on your TIU. If you have used the correct DCS block wiring, this should set up a double TMCC signal path to your engines, using both outside rails, giving you a very strong TMCC signal for your TMCC engines. If you have your DCS star wiring done correctly, both your DCS & TMCC engines will run perfectly.
PCRR/Dave
Paul Kallus posted:Ok, some of this (but not all of it) is coming back to me, kind of like calculus, once you resume it after years hiatus you find yourself remembering various tricks, and some other aspects you're back to the books.
Correct me on this: if I run a buss wire then I should install center-rail insulators?
yes, regardless of your wiring pattern Ross #904
If I do expand the existing wiring from central terminal strip (star wiring) in the layout expansion - around the room - and because have some decent long runs ~ 45 feet between a lift out bridge on one end and 45 degree crossings on the other (this is by its nature a block) - can I install just one feeder wire (from terminal strip) to that length of track or how many (old rule of thumb was feeders every 7-8 track connections)? And, from what I am reading thus far, center rail insulators are a good idea but may not be necessary?
10-12 track joints or feet per block, can vary some if it works out better with the track plan. Blocking your crossover will be key to keep the signal from running back onto itself. keep it within one block, perhaps the cross and a few track sections off of each leg.
Matt said: "At the ends of the buss itself, you should consider installing to prevent bounce-back at the end of the buss. The ends of the buss wires should not be connected into a circle, but should be terminated using "snubbers" aka "Deats Filters".
The solid state version of the "magic light bulb". http://www.slsprr.net/technical/filter.htm
What are these things, never heard of them?
BTW: am using Ross track.
I have an older buss wired layout with 100 percent perfect signal.
Well, it took a fellow in Atlanta (Legacy Station) to smoke out what was a very simple solution to my wiring problem. Turns out, during all this, I had shifted the drop cord connection to my TMCC command base to a two wire, non-grounded cord. Bingo. Everything works fine now.
Marty Fitzhenry posted:I have an older buss wired layout with 100 percent perfect signal.
Ditto, rev L TIU and all 10s
FRBOB,
Glad you found your problem, grounding is a major factor for both TMCC & Legacy, if you watch the Lionel Legacy Instruction Video it shows that the Legacy must be plugged directly into a well grounded wall outlet. Most multi plugs are not grounded properly and mess up the TMCC/Legacy.
PCRR/Dave
