Why DCS doesn't do the job for me

[DanteS]

In a previous post I pointed out that the latest product from MTH is not equipped with a DCC decoder. I really don’t mean to beat a dead horse, but before that thread was closed there were enough follow ups that I believe missed the point to such a degree that I would like to address the issue from a slightly different angle. I understand that there is a group of passionate MTH defenders, who appear to want to tell me that because DCS is good enough for them, it shall be good enough for me. Well, it is not: I own a large, beautiful steam engine produced by MTH. I just wish it would run better. Unfortunately, I can’t improve on the running characteristics because the manufacturer chose to incorporate a decoder that is not compliant with the NMRA DCC standard that my controller uses. MTH uses a DCS decoder, which can receive all DCC commands, but does not react to many of them. When I bought my engine I was aware that it had a DCS decoder because, in contrast to more recent releases, it was advertised that way. Consequently, I don’t feel cheated. I knew what I was buying. Pretty as it is, dynamically my engine behaves much like a toy. Before I go on, let me just state that I am a professional electrical engineer and I have personally visited MTH’s service department with my engine to verify that it performs according to the producers specifications. The core problem is that ALL MTH engines are speed matched so that each one of the 128 digital speed steps correspond to 1 mph. This produces a ludicrous top speed of 128 mph for my engine which had a prototype top speed of 10 mph. Although I run the engine a bit faster than that, the result of the speed mapping are extremely few steps within the desired speed range. Although one could argue that this step-resolution should be sufficient, in practice the engine shows noticeable jumps in speed as the throttle is increased. It is my understanding that the speed mapping can’t even be changed with a DCS controller. (In ant event I can't change it). So I have learnt to live with the way it runs. And I have reluctantly accepted the chatter from the cab. I am just not going to buy another one like it. About technical and legal definitions, I would like to add the flowing. A “receiver” is not a “decoder”. The generally accepted electrical engineering definition of a “receiver” is, not surprisingly, a unit that can receive signals. It doesn’t DO anything with that signal. The signal must be passed on to another unit that does something that the system designer desires. In the case of a model loco, this unit is the “decoder”. If you want DCC signals to be interpreted according to agreed upon DCC standards, that “decoder” must be a “DCC decoder”. That is why MTH does not have a problem with truth-in-advertisement as someone suggested they might. MTH undoubtedly chose their words very carefully. By stating that their engine has an on-board DCC “receiver”, they are 100% correct. Your new $500-engine will indeed RECEIVE all DCC commands – unfortunately legally it doesn’t have to DO anything with them. It MAY do some things, but if it isn’t what you expected, you are out of luck. You have just fallen victim to smart marketing. I have to admit that I did make a trip to the local hobby store to check out the new Cab Forward, because, even with my background, I was duped by the “DCC receiver” term. – Sometimes I am a hopeless optimist. So I hope that with your needs in hand, and the insights you may have gained by reading this, you will be able to make an intelligent purchasing decision if you are interested in a Cab Forward.

[ATLANTIC CENTRAL]

Dante,

I for one got your point very clearly the first time but thank you for the detailed explaination.

As a DC operator, I feel they play "fast and loose" with their comments about DC compatibility as well.

I won't be buying any until they offer them without DCS and offer them DC/DCC ready.

Sheldon

[tomikawaTT]

Like Sheldon, I operate with analog DC.  I can also live without sound, smoke and speed matching.

If MTH ever goes out of its collective mind and produces a JNR D51 in 1:80 scale 16.5mm gauge, then sells it at significantly less than the MSRP (plus international shipping and money exchange charge) of the same loco made in Japan, I'm sure I'll be able to figure out how to gut the on-board electronics and wire it for standard DC pickup, with a directional circuit for the headlights front and rear.  If they ever decide to market it WITHOUT the DCS decoder that would save me the effort.

Chuck (Modeling Central Japan in September, 1964 - with 1964 control technology)

[selector]

I wonder what the price drop would be with a strictly DC/DCC-ready version.  I suppose if they could be had for about $120-160 they might have a market, but I'm afraid guys like Sheldon won't be so keen when Bachmann or other manufacturers have the same thing in plastic for $70-100.

-Crandell

[ATLANTIC CENTRAL]

selector

I wonder what the price drop would be with a strictly DC/DCC-ready version.  I suppose if they could be had for about $120-160 they might have a market, but I'm afraid guys like Sheldon won't be so keen when Bachmann or other manufacturers have the same thing in plastic for $70-100.

-Crandell

Bachmann and Athearn in particular try to avoid doing stuff already done by others for the most part (there are few exceptions), so the real key would be for MTH to do something that has not been done, and something that is of interest to those of us who model the "ordinary".

And of course to offer it in DC/DCC ready.

Sheldon

[Hamltnblue]

 I'm sure they'll come around to DCC ready eventually but one of their problems is their common.  When I Converted my SD70Ace's i found that the DCS system used a Negative Common,  DCC uses positive.  This would require different wiring and circuit boards on the DCC ready version when they come out.  For production it increases cost.  It might be why they haven't jumped on it sooner.

[Hamltnblue]

Here's the link to the thread when I converted my first one:

http://www.modelrailroadforums.com/forum/showthread.php?t=15653&page=11

Post #108 in the thread is where I have to modify the light board to accommodate the polarity difference.

For those who are interested the conversion started on page 11 of the thread and is spotted throughout with pics. 

[Heritagefleet1]

DanteS

– Sometimes I am a hopeless optimist. So I hope that with your needs in hand, and the insights you may have gained by reading this, you will be able to make an intelligent purchasing decision if you are interested in a Cab Forward.

I'm going to keep this nickels worth to a minimum as I was a part of the last topic.

Based on what you have just stated, your problem may be with the throttle settings - not the locomotive.

I'm only suggesting - your engine, may be operating in 28 speed step mode - not 128 - which would explain the more 'toy-like' performance that you describe.

As an engineer, I'm kind of surprised that you don't understand why MTH designed the speed steps for matched 1 scale MPH per speed setting.

This produces superb 'start', 'slow' and prototypical 'track speed', in the scale you're modeling, for beginners and advanced operators.

I must have 7 or 8 of their steam models and they have the very best operating speeds you could possibly ask for - as for your argument about 'ludicrious' top speeds, I don't think anyone is going to bury their throttles with a desire to intentionally operate at those settings.

Again to be clear...I think you need to check to insure that your throttle is in 128 speed step mode. I don't know what command system you are using so you'll have to refer to the speed step preference portion of your Command System owners manual.

To address your comments about the cab chatter,  it is user adjustable in the sound recipes - you have to have a 28 function throttle to access that feature - Chatter 'ON'/'OFF'.

This does not affect the F4 station announcements seq 1,2,3 and 4 but since you don't like this feature then you probably don't use F4 anyway.

As a comparision, one of my fellow members of a local Club just got the modern version and had it running at the club. It ran awsomely from a absolute crawl start up to about a scale 25 MPH, with 44 reefers and a caboose in tow... it performed flawlessly on the club's scale 1.9% mainline grade -no stalling, no wheel slip. Using a Digitrax 402 throttle, I adjusted the cab sounds to OFF and adjusted the individual sound levels for the whistle, bell and ambient sounds, with a track interface unit.

I don't know what else can be said, unless you just don't want the model. It is possible that you have a 'bad' engine - it happens to everyone.

If the speed settings are selected for 128 speed step mode, and the engine is operating as poorly as you suggest here, then I'd return it and ask for a replacement or a refund.

Rick

 

 

 

 

 

 

[Bluegill1]

Hi Rick, This is off the original topic, but I noticed you mentioned "using a Digitrax 402 throttle" I adjusted the sounds. I am new to HO and DCC, I was told (from those that have Digitrax) that Digitrax does not support sound. Am I mistaken, could you help clarify? Thanks, David

[Heritagefleet1]

Bluegill1

Rick, This is off the original topic, but I noticed you mentioned "using a Digitrax 402 throttle" I adjusted the sounds. I am new to HO and DCC, I was told (from those that have Digitrax) that Digitrax does not support sound. Am I mistaken, could you help clarify? Thanks, David

David...

I don't know who told you that Digitrax does not 'support' sound...I think there needs to be clarifiaction here, since you are new to DCC. It sounds to me like they are confusuing you...i'll try to help.

First of all, all of today's Digital Command Control(DCC) systems, are NMRA compliant and they all support a minimum of 10 functions, not sound itself. The Command system nor throttle - have nothing to do with Sound capability.

Todays sound decoders offer much more sound and setting capability thus more available function control was required.

MRC was the first DCC manufacturer to support 18 functions and in the last year, just about everyone has upgraded their throttle system to incorporate NMRA 28 function capability.

If you have the most basic DCC control, you can operate a sound locomotive or decoder.

The previous generation Digitrax throttles would only give you up to 12 functions on the DT400 throttle.

The 402/402D throttle that has recently hit the market , gives you access to the full compliment of 28 functions.

So, lets say you have a MTH locomotive, or an Athearn Genesis engine, that are decoder equipped. If you are using a 'older' throttle, you will not have access to all the features the engine has onboard.

Extended start up, shut down , sound file recipes, additional on/off features,lighting control, quilable whistle,sound volume settings, etc - there are lots depending on which loco you're talking about. Many user installed decoders allow you to adjust some- but not all - of these settings by changing the Configuration Variables(CV's), others do not.

If those features are not important, then  its hard to justify upgrading your current throttle.

I have a wide range of equipment that is decoder equipped so I want the full array of functions at my fingertips.

If you are using a Digitrax DT400, you can have it upgraded to 28 function capability for $50 - you have to send it back to Digitrax for the modification.

The drawback is your without a throttle while its being upgraded. I just buought mine about 2 months ago and am going to send my older DT400 in for upgrade - one I get that back, I'll have two throttles as an extra for operating or as a spare.

Most guys end up with two or more throttles anyway as their layouts expand.

Anyway, your throttle has nothing to do with sound control.

Let me know if this helps you out...and if not, let me know if I can help more.

Welcome to the 21st century of Model Railroading.

Thanks,

Rick

HeritageFleet1

 

[rrinker]

 Dependign on how the decoder supports it, quillable whistle ahs been a feature that was in the DT400 almost fromt he beginning. A very few of the early ones made don;t have the touch sensitive switch for F2, but the majority do. The DT402 continues that feature. This became a sort of psuedo-standard to use F2 and vary it somehow to quill the whistle, NCE does it by using the whistle buttona nd the thumbwheel. Not all decoders support it, and it wouldn;t surprse me if the MTH DCS decoders use a compeltely different method - if it's even possible when operating under DCC.

 ANd yeah. I've love to know who made the staement that Digitrax does not support sound. Someone who shoudl not be giving DCC advice, or sellign DCC equipment, that's for sure.

                             --Randy

 

[simon1966]

Bluegill1

I was told (from those that have Digitrax) that Digitrax does not support sound. Am I mistaken, could you help clarify?

David, Digitrax makes sound decoders, it would be a bit odd if their own DCC systems could not support sound!  Have no fear, I have been controlling sound equipped locos with my Digitrax equipment from soon after the release of the first Broadway Limited steamer, some years back.

[Bluegill1]

Rick, Randy, Simon, Thanks for the clarification. Next time I get together with the group I'll try to remember to ask and see where I got the wrong idea. Sincerely, David

[Texas Zepher]

Bluegill1

Rick, Randy, Simon, Thanks for the clarification. Next time I get together with the group I'll try to remember to ask and see where I got the wrong idea.

  It  is not hard to get the wrong idea.  There are still those who consider onboard sound synonymous with DCC,. 

[Hamltnblue]

 Yes, many DC loco's consider on-board sound to be the loud gear noise they emit.

 

[WSOR 3801]

Hamltnblue

 Yes, many DC loco's consider on-board sound to be the loud gear noise they emit.

 

 

That is Athearn sound.  Sometimes I prefer it to QSI sound.  At least the Athearns would usually run together.  I'm still having fits trying to get my P2K QSI engine to run with anything else.  It won't pull much by itself either.  

 

[ATLANTIC CENTRAL]

WSOR 3801

Hamltnblue

 Yes, many DC loco's consider on-board sound to be the loud gear noise they emit.

 

 

That is Athearn sound.  Sometimes I prefer it to QSI sound.  At least the Athearns would usually run together.  I'm still having fits trying to get my P2K QSI engine to run with anything else.  It won't pull much by itself either.  

 

That's funny.

Personally I prefer the sound of the metal wheels going click-clack on my 45 car trains over gear noise or computer regenerated static through 1" speakers.

Hamltnblue, when does that new Berkshire go to the paint shop for a little light weathering?

But what do I know I'm just a hick with a pickup, some guns, and some DC powered model trains.

Sheldon