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Digitrax DT402 PO and Loksound

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  • Member since
    April 2001
  • From: US
  • 416 posts
Posted by blabride on Monday, June 13, 2016 9:40 AM

Yes Randy is right when I thought about it some more I realized when I changed the addresses I also went throught the full programing on the Powercab that I do when I install a sound decoder and set speed tables to off. So I have them back to 146 and 147. These were bought with onboard sound so I must have skipped this step in a hurry. 

SB

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, June 12, 2016 7:03 PM

146 and 147 are both long addresses to Digitrax and all the other systems.

Lenze skipped the full use of the 7 bits allocated for the address field and only goes 1-100 for short addresses, 101+ is a long address with Lenz. This makes for some portability issues between some systems, a Lenz loco with address 110 will work on Lenz or NCE but not Digitrax, a Digitrax loco at 120 will run on NCE or Digitrax but not Lenz.

146 and 147 should not be a problem - what I suspect is what others have said - speed tables were enabled, so when you reprogrammed to 1146, the automatic setting for CV29 simply put the standard value which is for long addressing, 28/128 speed steps and, with most systems, automatic analog ooperation. This reset the bit in CV29 used to activate speed tables and now the values in CV 5 and 6 worked.

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    February 2007
  • From: Christiana, TN
  • 2,134 posts
Posted by CSX Robert on Sunday, June 12, 2016 6:15 PM

blabride
The GP60M have addresses under 150 once I added a 1 to make them 1147 and 1146 it makes the changes on the track in ops mode.

If you were able to acquire and control them with the prvious address, you should have been able to program too.  Is it possible that the speed table was enabled (causing the decoder to ignore CV5 and 6), and when you reprogrammed the address it disabled the speed table?

blabride
It usually won't acquire any loco I have under a certain number

If you are programming addresses using your Power Cab, make sure that if you program an address below 128 you program it as a "2-digit" (primary) address.  The Power Cab supports both "2-digit" and "4-digit" (extended) addresses below 128, but Digitrax only supports "2-digit" addresses below 128.

  • Member since
    February 2007
  • From: Christiana, TN
  • 2,134 posts
Posted by CSX Robert on Sunday, June 12, 2016 5:52 PM

blabride
The weird thing is the DT402 is telling me good when I make the changes, not a fail but yet the cahnges are not being made.

When doing ops mode programming ("programming on the main"), the DT402 always says good because the ack pulse readback mechanism is not supported in ops mode.

  • Member since
    May 2002
  • From: Massachusetts
  • 2,899 posts
Posted by Paul3 on Sunday, June 12, 2016 4:27 PM

blabride,
Perhaps a review of addresses and CV29 might be helpful:

In yon olden days of yore, DCC was invented by Bernard Lenz, and he thought that a 2-digit loco address would be plenty.  An older analog control system called "CTC-16" only had 16 addresses, so a digital system with 0-99 addresses was considered plenty at the time. 

But to squeeze even more out of just 1-digit, Lenz used hexadecimal digits, meaning that the numbers had 6 extra characters: 0 1 2 3 4 5 6 7 8 9 A B C D E F.  So instead of just 0 to 9, he got 0 to F (or 15 in decimal).  To make it take up less memory, just one byte in hex was used for addresses.

For one byte in DCC, the number range is from 01 to 0F.  0F is 127 in decimal.  Therefore, the original DCC set up used only addresses from 1 to 127.

Later, 4-digit addresses were considered better because one could just use the loco's real number instead.  To make it work, 2 bytes were used for the address, but then for it to work on the existing DCC system, the decoder has to be told which one it is: 1 byte or 2 bytes.  This is controlled on the decoder by CV29.

If you program your loco to a number from 01 to 127, CV29 should be a decimal value from 00 to 23 (normally 02).  If you program your loco to a 4-digit address, then CV29 should be from 24 to 55 (normally 34).

You must remember to change CV29 correctly whenever you program a number into a decoder.  If you don't, it won't respond to throttle commands or programming commands.

Paul A. Cutler III

  • Member since
    April 2001
  • From: US
  • 416 posts
Posted by blabride on Sunday, June 12, 2016 2:27 PM

I have a couple of lit passenger trains one 11 cars and one 8. The 11 car train has a set of brass hallmark E7's with Wow decoders.I also tend to run MUed three unit freight sets. I'll does some adding from my Powercab at the bench. It would be nice if the Zephyr would be enough power.

Thanks Again,

SB

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, June 12, 2016 2:08 PM

 How many locos are you running? The Zephyr Xtra is 3 amps, that should easily run 8-10 sound locos.

 The Zephyr Xtra can run 22 locos, so if you added a DB150 you'd have plenty of power. The Zephyr would still be the command station so you have the program track and readback.

 If you're only adding a second throttle, you likely don;t need any extra power and you can continue on as you are with nothing more than the extra throttle.

                           --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    April 2001
  • From: US
  • 416 posts
Posted by blabride on Sunday, June 12, 2016 9:59 AM

The problem seems to be solved. The GP60M have addresses under 150 once I added a 1 to make them 1147 and 1146 it makes the changes on the track in ops mode. It usually won't acquire any loco I have under a certain number but it would let me acquire these and run them. Tricked again by the idiosyncrasies of the digitrax system. Which I still have grown to prefer for the layout over the NCE.

Randy,

I see that I am going to need more power since I am expanding the layout some. I currently have a Zephyr extra and a DT402. I thought I would get another DT402 but what Command Station/Booster should I add. A DSC100 or a DB150? If I program most everything except speedmatching at the bench would I need the programming track feature of the DSC100? Are there any other benefits the DSC100 has the DB100 does not

Thanks

SB

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, June 12, 2016 9:29 AM

 As long as there is an ACK pulse fromt he decoder, the DT402 will say good when it programs a CV. That doesn;t necessarily mean the value you set got programmed in - to verify it you need to do a CV-RD and read back the value (if your system supports readback - if you have a DB150 then you can;t read back, or if you are programming on the main and not the program track).

                         --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    April 2001
  • From: US
  • 416 posts
Posted by blabride on Saturday, June 11, 2016 10:49 PM

Good point will check that in the morning. The weird thing is the DT402 is telling me good when I make the changes, not a fail but yet the cahnges are not being made. I know that by checking with my Powercab which does let me make changes to them.

SB 

  • Member since
    January 2001
  • From: SE Minnesota
  • 6,847 posts
Posted by jrbernier on Saturday, June 11, 2016 6:41 PM

  CV5 & CV6 are to set max and mid speed.  Is the speed table set on?  This will usually disable CV5 & CV6...

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

  • Member since
    April 2001
  • From: US
  • 416 posts
Digitrax DT402 PO and Loksound
Posted by blabride on Saturday, June 11, 2016 5:58 PM

Hello,

Anyone have any idea why a Foxvalley GP60M would not accept CV changes to CV5 and CV6 on a Loksound but the GP60B with the same factory decoder will? I have two GP60Ms both with the same factory Loksound decoder as the GP60B but both will not let me POM with the DT402 like the GP60B. They will let my change CV's just fine at the bench with a Powercab. Trying to finesse the speeds with an Accutrack Speedometer.

Thanks

SB

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