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A quick DCC question (hopefully!)

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  • Member since
    December 2007
  • 6 posts
A quick DCC question (hopefully!)
Posted by rbakerphoto on Friday, February 29, 2008 10:27 PM
I recently bought a NCE Power Pro 5 system. My layout is an L shape 6' x 8" figure 8 over pass with two spurs. I plan to use this as my test track and one of the spurs as a programming track. I purchased a Kato SD 90 Mac a couple of years ago and recently bought a decoder for it. (MRC decoder)
My question is this: Is a figure 8 a reverse loop? I know with DC I had to cut one rail to make the DC work, do I need to cut the other rail to make the DCC to work to avoid having a short?
I plan on a large future expansion later and want to use this section as my test track. I also purchased two Kato SD 70 MACs and sound decoders, but that is another question and confusion for later.
Thank you all in advance for your advice. This forum has been a great help, I just wished it could help me with my old age and stupidity!!
Robert
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  • Member since
    June 2003
  • From: Northeast OH
  • 17,199 posts
Posted by tstage on Friday, February 29, 2008 10:44 PM

Robert, 

No.  A figure 8 is NOT a reversing loop.  A reversing loop is where a track circles around and comes back on itself via a turnout: (See left side of diagram)

Click picture to enlarge

This means that a train will go down the track in one direction and return on the SAME track going in the opposite direction.  If your layout is an over 'n under figure 8, it's not a reversing loop.  However, if you had to "cut your track" in order to get it to work, then it does sound like a reversing loop.

In DCC, you'll still need to isolate the rails.  However, there are auto-reversing loop modules that will automatically sense and change the polarity of your track for you.  Lot nicer than having to remember to throw a slide switch.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    December 2007
  • 6 posts
Posted by rbakerphoto on Saturday, March 1, 2008 7:50 PM
Tom I realize that it is not a reversal loop but the polarity on the rails switch when the figure 8 is complete.
Robert
  • Member since
    February 2005
  • From: Vancouver Island, BC
  • 23,321 posts
Posted by selector on Saturday, March 1, 2008 9:38 PM
No they don't, Robert, not if you have a properly configured crossing.  If you are getting a short you have something else amiss...maybe crossed wires.
  • Member since
    July 2006
  • From: Vail, AZ
  • 1,943 posts
Posted by Vail and Southwestern RR on Saturday, March 1, 2008 11:21 PM

 selector wrote:
No they don't, Robert, not if you have a properly configured crossing.  If you are getting a short you have something else amiss...maybe crossed wires.

Or we have different pictures in our heads when we say figure 8.

Jeff But it's a dry heat!

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