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MRC decoder failure?May be not,I'm not sure...

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  • Member since
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  • From: City of Québec,Canada
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MRC decoder failure?May be not,I'm not sure...
Posted by Jacktal on Sunday, May 10, 2009 4:45 PM

A little while ago,I purchased an Athearn N scale Challenger (brand new).By then,I didn't have a layout to run it so satisfied myself with programming the new adress with my Digitrax equipment (DCS-200/DT-400) using a length of track.Although it didn't program with the first mode,it went fine using an alternate method described in the DCS200 manual.Then it was put back in its case until today.

I just finished a temporary (test) layout,so time has come to pull it out of the case for a few laps.It ran fine until I accidentally created a short at a turnout wich was away from my loco however.I mean the loco wasn't involved with the short in any way other than stopping during the current shut down.But it didn't restart after the current came back to it,it simply sounds its steam cycling (in idle mode) but impossible to get it to run,just like it has become deaf to DCC commands.

I supposed that it had had its adress memory erased and had returned to its original 03 adress like has happened to me once with a Digitrax decoder,but such is not the case.It doesn't respond at all.Is it a typical MRC decoder illness or should I try to reprogram it and hope it'll hold for a while this time.The loco has run about five minutes.I'm planning to retrofit this one and my Big Boy with Tsunami's some time in the future (their sounds aren't that great anyway) and I'm saving for this,but if I'm going to have to reprogram every time another loco enters a wrongly thrown turnout,I'll consider doing it sooner.

  • Member since
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  • From: Shalimar. Florida
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Posted by Packer on Sunday, May 10, 2009 4:54 PM

Have you tried recalling the decoder? On your controller, re-enter the loco's address and see if that helps.

All else fails, just reprogram the address on the Programming track. I've had to do that once with my F45 with sound/dcc.

Vincent

Wants: 1. high-quality, sound equipped, SD40-2s, C636s, C30-7s, and F-units in BN. As for ones that don't cost an arm and a leg, that's out of the question....

2. An end to the limited-production and other crap that makes models harder to get and more expensive.

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  • From: Charlotte, NC
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Posted by Phoebe Vet on Sunday, May 10, 2009 4:56 PM

First I would shut the entire system down and restart it.

If that doesn't work, try resetting the decoder to the factory defaults and then reprogram it.

Dave

Lackawanna Route of the Phoebe Snow

  • Member since
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  • From: Westchester NY
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Posted by retsignalmtr on Sunday, May 10, 2009 6:57 PM

i installed two mrc sound decoders into atlas n scale diesels. after installation they ran well and sounded good for several months. then one loco stalled and would no longer move despite being reset to factory specs and then reprogrammed to the locos address. all it does is idle with occasional compressor sound and air bleedoff. the other loco with the mrc sound will not make it around my layout without stalling at least 2 or 3 times and not in the same areas. the sound goes off and then it throttles up and starts to move again. i won't waste any more $ on mrc decoders in any scale.

  • Member since
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  • From: City of Québec,Canada
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Posted by Jacktal on Sunday, May 10, 2009 8:51 PM

Thanks for the answers.I will try reprogramming its adress again the way I did the first time.I strongly wish I don't have to change  CV's though,as this is much like chineese to me.There are CV "suggestions" that came with the loco but I've never learned how it goes nor do I know if my PR3 is compatible with MRC decoders.The last time,the adress was programmed on the main.

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  • From: Massachusetts
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Posted by Paul3 on Sunday, May 10, 2009 9:16 PM

1). MRC sound decoders always shut down after the power goes off for any reason.  This includes short circuits.  So if you are running it and you have a short, you have to "wake it up" every time.  The specific instructions for waking up MRC sound decoders should be in the manual.

2). MRC sound decoders are infamous for going bye-bye on DCC.  I have had many just lose their address (for many reasons) and you just don't know what it is.  Since MRC decoders don't support read back (like every other decoder manufacturer in the world), the "new" address will remain a mystery forever. 

The only thing to do is to either reset the decoder to factory defaults, or use "burst" mode programming on the mainline.  That last is a little dangerous because you risk programming all your locos to the same address.

To "burst" program a loco on the mainline, isolate the DCS200 "Rail A" and "Rail B" connections from your layout and connect them directly to an isolated piece of track.  Also, isolate the LocoNet as well from the rest of your layout if you have any other boosters.  At this point, you should only have the DCS200 with a DT400 plugged into it connected to an isolated piece of track with the MRC sound loco on it. 

On the DT400 and without selecting an address (and if that doesn't work, select address "00"), select program "Po" mode (Ops Mode) with the PROG button.  Now enter the address in the normal way, then hit ENTER to program the loco.  This "forces" the decoder to take the address.  Again, if you don't isolate the layout, you risk programming every loco on the layout to the same address

If all of that doesn't work, try returning the loco to Athearn...or rip it out and replace it with something that works.

Paul A. Cutler III
*******************
Weather Or No Go New Haven
*******************

  • Member since
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  • From: City of Québec,Canada
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Posted by Jacktal on Sunday, May 10, 2009 10:27 PM

I did just that and it worked.I simply reprogrammed the adress and it digested it.I had a feeling that was what had happened as it did happen to me with a regular DCC Digitrax decoder in the past.However,it is a somewhat upsetting situation that I will tolerate for a little while until my budget allows me to replace these two decoders.I've been recommended Tsunami's (DavidMBedard) and have heard very good things about them elsewhere too,so this is my choice.My only worry is that I might have to purchase special hardware to program them if neither my Digitrax setup nor my computer/PR3 combo aren't up to the task.

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  • From: Thornton, CO
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Posted by jwils1 on Monday, May 11, 2009 12:03 PM

Paul3

2). MRC sound decoders are infamous for going bye-bye on DCC.  I have had many just lose their address (for many reasons) and you just don't know what it is.  Since MRC decoders don't support read back (like every other decoder manufacturer in the world), the "new" address will remain a mystery forever. 

Just a small correction Paul.  MRC is currently producing decoders with CV read back.

Jerry

Rio Grande vs. Santa Fe.....the battle is over but the glory remains!

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  • From: Good ol' USA
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Posted by AntonioFP45 on Monday, May 11, 2009 9:22 PM

* The following is not an official advertisement yada-yada,-blah-blah, etc etc.,*

 

But............here's a large scale illustration as to what modelers can do with MRC sound decoders. (good opportunity for a short, but energetic exercise workout) Big Smile:

http://blog.everydayscientist.com/wp-content/uploads/car-crushed-earthquake.jpg

"I like my Pullman Standards & Budds in Stainless Steel flavors, thank you!"

 


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Posted by jwils1 on Monday, May 11, 2009 10:47 PM

AntonioFP45

* The following is not an official advertisement yada-yada,-blah-blah, etc etc.,*

 

But............here's a large scale illustration as to what modelers can do with MRC sound decoders. (good opportunity for a short, but energetic exercise workout) Big Smile:

http://blog.everydayscientist.com/wp-content/uploads/car-crushed-earthquake.jpgI 

I don't know.......it looks more like the results you might get from a "Tsunami" to me!!!

Jerry

Rio Grande vs. Santa Fe.....the battle is over but the glory remains!

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Posted by maxman on Tuesday, May 12, 2009 9:20 AM

Paul3
MRC sound decoders always shut down after the power goes off for any reason.  This includes short circuits.  So if you are running it and you have a short, you have to "wake it up" every time.  The specific instructions for waking up MRC sound decoders should be in the manual.

Could you please explain what you mean by this, especially the "always shut down" and "wake it up every time" parts?

I have a Sheer Brilliance 1643 EMD modern diesel sound decoder installed in an Atlas GP38-2.  I just went down to the basement and did some experimenting to confirm what I originally thought, which was that your statement is not necessarily 100% correct.

When I first started up the DCC system, the sound started immediately from this decoder.  I then applied a direct short to the rails in front of the engine.  The sound stopped, and then resumed when I cleared the short.  I then got the engine moving w/sound and applied the short again.  When I cleared the short, the sound resumed and the engine started moving at the same speed it was prior to the short.

As far as the "wake it up" thing goes, there is a note in the instruction that says the engine has a start up and shut down feature, and that you have to press a function key to start up the engine before operating.  However, I found that the only way this feature occurs is if I manually shut the engine down by pressing the F8 key three times as per the instruction.  If I don't do this, the decoder will not shut down on its own.  The engine will run when asked either on power up, or after a short.

Of course, I suppose that I actually have a faulty decoder because it doesn't follow the always and every time rules.

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Posted by CSX Robert on Tuesday, May 12, 2009 9:58 AM
Paul3
1). MRC sound decoders always shut down after the power goes off for any reason.  This includes short circuits.  So if you are running it and you have a short, you have to "wake it up" every time.  The specific instructions for waking up MRC sound decoders should be in the manual...
The only MRC sound decoder I have any experience with is the one in the Athearn N-scale Challenger(which is the one giving grief here),and I can say with certainty that it does not "shut down," and there is no procedure to "wake it up."
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Posted by Paul3 on Tuesday, May 12, 2009 12:33 PM

jwils1,
Which decoders would those be?  It's not the Atlas S-unit decoder, the Athearn F-unit decoder, the Roundhouse steam decoder, etc. that I've tried.  Have they upgraded the software of these decoders, and if so, is there any way to tell if they have or not?  What I mean by this is that when Digitrax updates their decoders, they change the ID number.  The DH120, DH121, & DH123 are all the same decoder (1 amp, 2 functions, and shrink wrapped), but the higher number decoder has better features.  Has MRC done so?

maxman,
When the Athearn SD45's with MRC sound first showed up at my club, a member named Doug managed to get three of them running on the layout.  He had them on a train, and was hauling 30+ cars around our Digitrax layout.  Someone in front of him left a switch thrown, and Doug ran into it.  Fortunately, he wasn't running that fast, and the train only shorted out on the frog...it didn't derail.  Since our mainline switches are run on their own dedicated DB200 booster, Doug was able to clear the switch without moving the track back off the frog.

After power was restored, all three engines were silent.  He tried to move them, and they would not.  He tried activating a function, the lead engine started making sound and started to move but the other two SD45's would not.  After calling me over, I thought perhaps they lost their MU.  So I used his DT400R throttle, plugged it in, and aquired the 2nd unit on the left knob.  Once I did, I broke the MU and it still wouldn't move.  I then tried a function, and the loco started up and would move.  I re-MU'd it to the first loco, then selected the third unit.  This time, I just tried a function, the loco started right up and would move with the first two.

Months later, I was at the Springfield (MA) show, and talked with the MRC factory reps manning their table.  I asked them about this situation, and not only did they confirm it, they also said that if people wanted, they could send in their MRC sound units still attached to the chassis but without the body in the original box to MRC, and they would reprogram them so that they would not do that any longer.

Now, maybe they've changed their motion & sound decoders so that they no longer have that feature, but since MRC sound has been mostly shunned at our club ever since they came out I admit that I could be mistaken.  But when you see it with your own eyes and have a factory rep confirm it, you might understand why I said what I said.

Paul A. Cutler III
*******************
Weather Or No Go New Haven
*******************

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Posted by maxman on Tuesday, May 12, 2009 12:45 PM

Paul3

Months later, I was at the Springfield (MA) show, and talked with the MRC factory reps manning their table.  I asked them about this situation, and not only did they confirm it, they also said that if people wanted, they could send in their MRC sound units still attached to the chassis but without the body in the original box to MRC, and they would reprogram them so that they would not do that any longer.

You are absolutely correct re: the SD45.  I was at the same show, asked the same question, and got the same answer.  Matter of fact, I passed this information along to a friend of mine who had 6 or 7 of the SD45s and he did send them back for re-programming.  He's a lot happier now.

I was only taking issue with the "always" and "all the time" statements, and wanted to point out that this was not always the case.

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Posted by jwils1 on Tuesday, May 12, 2009 7:43 PM

Paul3
jwils1,
Which decoders would those be?  It's not the Atlas S-unit decoder, the Athearn F-unit decoder, the Roundhouse steam decoder, etc. that I've tried.  Have they upgraded the software of these decoders, and if so, is there any way to tell if they have or not?  What I mean by this is that when Digitrax updates their decoders, they change the ID number.  The DH120, DH121, & DH123 are all the same decoder (1 amp, 2 functions, and shrink wrapped), but the higher number decoder has better features.  Has MRC done so?

Paul,

MRC's sound decoder for the Atlas S2/S4 now has CV read back.  I have two of them.  The older one does not read back but the newer one does.  Also, their #1820 for Athearn RS3 reads back.  The best way to tell is to look at each decoders manual on their website as read back is listed in the list of features if it's included.  Didn't notice any difference in their model numbers.

I remember reading somewhere that they were starting to include read back so that's probably the case on current production.  If buying from a supplier's older stock one might not get the read back.  Don't know if quality is getting better but my two do work well with excellent motor control, but of course they have the wrong sound. 

Jerry

Rio Grande vs. Santa Fe.....the battle is over but the glory remains!

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