First layout - struggling with control system choice

As I don't have any existing investment in any system, my options are wide open. On the one hand, DCC is a well-established system with tons of different equipment and modules available. I've been looking into the Roco Z21 system, and it seems to address most of my concerns with DCC...most.

The fact of the matter is that DCC is long in the tooth - nearly a quarter century, which, let's face it, is ancient for any digital system. It does seem that the industry has done well with it over the years, but I wonder if it's been pushed about as far as it can go. I'm an enterprise computer systems analyst and programmer, and I can tell you that there is just no excuse for a user having to deal with things like functions and CV codes in this day and age. Better methods of device communication and interfacing became mainstream over a decade ago. For all I know the NMRA is about ready to ratify a new and expanded "DCC 2.0" specification. I've done some searching, but I haven't found anything to indicate such. It sure is due for one, though.

One of the more recent and significant innovations in command control, at least as it occurs to me, is wireless, bidirectional communication systems, that not only allow the locomotives to communicate back to the command station but also with each other. I am very impressed by what I've seen from the RailPro system. Not only does it appear to be a trivial matter to MU multiple locos (a matter of seconds start to finish, including configuration/calibration of each loco), but it enables them to actually do active and constant load sharing, as the train travels through curves and over grades. Also - and this is more than a little subjective, I'll admit - the graphical interface looks significantly more intuitive than, say, that of a DigiTrax DT402D, or pretty much any other DCC throttle (with the exception of the tablet/smart phone interface of the Z21, which is pretty amazing).

The primary factors giving me pause regarding RailPro are, 1) it's a proprietary system, and 2) in the years it's been around, it doesn't seem to have progressed very quickly. The first point, while not ideal, wouldn't concern me too greatly, if it weren't for point #2. Things like still having no N-scale support and no options for more robust graphical command devices like tablets. I'm not about new gadgets for the sake of new gadgets, but have you seen what Roco has done with the Z21? And that's using DCC.

I get that people with a sizable investment in DCC probably have little interest in something like RailPro, and I don't blame them, but for someone just getting into the hobby, it's a compelling option.

I'll wire my layout for DCC, as that approach works for both, but at this point I'm really torn between the Z21 and RailPro. I'd like to hear from those who have or are using either of them, and also from others who maybe haven't, but wouldn't mind offering their thoughts on sticking with DCC or going all in with the new tech in RailPro (or some other similar competing product I may not have considered).

Thanks,
Rich

 

Rich

It probably depends on how far you want to go and in what scale you are modelling as to whether a wireless system is worth considering. Its time is probably not here yet when it can do all that you may need.

You have already seen the size issue where the current wireless offerings are still much larger than comparable DCC components. They will become smaller with time, but so will the DCC components so I suspect there will always be a gap between the two technologies.

There is also the security of the connection to consider too. The wired connection via the track is not only unhackable, but provides for very low latency between giving commands and the train or accessory responding. With traditional Wi-Fi and Bluetooth solutions not only do they have to be secured against hacking which creates a little latency, there is only limited bandwidth available that can quickly be eaten up causing increased latency if you have a lot of radio devices running at the same time. Go to any big event nowadays and the 2.4GHz band will be swamped with users downloading sports results or watching highlights - add to that every layout at a train show using it as well and you could come unstuck. There is also the issue of local interference being generated at the wheels if the train is picking up power from the track. All of this can induce potential problems if you are going to be a heavy user, or be operating in a busy environment. Bluetooth systems will be especially prone with less than ideal receiver aerials because of the small size and no central infrastructure to boost the signal.

If you have a small number of trains and larger scales you probably have a choice, but otherwise you would probably be best going with DCC.

From an operator perspective there is probably little difference to note between using traditional DCC accessed via a wireless device and a full wireless system - and you are not just limited to the new Z21 style systems, most can be interfaced to Wi-Fi by some means or other anyway to give you the best of both worlds.

Suzie x

 

Rich,

I can't offer expert advise on the systems, but I can offer my experience from the information technology world. Over the last 30 years I have seem one proprietary system after another fall to a ubiquitous system often coming out of merging solutions. IT companies have learned that by allowing open access to technologies their product proliferates. This has been accelerated by crowd sourced solutions where all sorts of unaffiliated people come together and develop products that are generally given away.

In this case you have to ask, 1) What is the probability that the solution I choose remains supported by 3rd party vendors supplying accessories? 2) What level of interaction do I want with others e.g. Clubs, shows or friends? 3) Can I live without the proprietary features that are missing from the perceived standard? 4) Is there a hybrid solution that satisfies both worlds, as Suzie mentioned?

As I started with DCC a month ago, I am new to this. So I have been doing a lot of reading. Others more knowledgeable than I please chirp in here if I am incorrect but, as I read it DCC has a standard set of functionality defined and each vendor supporting DCC is required to meet that set, however; the vendor can extend these functions so, and this is where I need the others to keep me honest here, you may have some vendors utilize more CVs than others. Given NMRA defines the DCC protocol, NMRA will push the protocol in the direction their members want. Accordingly it will evolve and new functionality will emerge. The same is true for WiFi where we have seen standards change over the years pushing speeds ever higher. Cell phone industry got together to agree 3G, 4G and now Google is suggesting 5G etc.

It's a choice over longevity of your investment. There is no right answer. Please who bought Betamax still recorded shows and watched them, they just saw there player become more and more obsolete, much like my gen 1 iPad I can't upgrade it and almost daily the apps I have cease to work.

All the best in your deliberations, keep us posted.

Russ

 

Suzie and Russ, thanks for chiming in.

Suzie, as far as wireless concerns go, I'm not particularly concerned with any perceived hacking risks. I have much more important stuff going on on my wireless network at home (hackable from the street outside my house or pretty much anywhere on the internet), yet I use it daily. As for public scenarios, your train set doesn't have to be connected to the internet or anything outside of your layout. Regarding bandwidth issues, they only apply if everyone is connected to the same IP address or subnet. With over 4-billion IP addresses to choose from, I doubt that would ever be a problem. Interference from the track to wheel connection could be a potential concern in theory, but no one seems to be having any problems with that, so someone way smarter than I must have considered that during design.

Russ, this will be on my stationary home layout, so I don't really need to worry about what everyone else is using. The local N-Trak club that I'm planning to join (my first layout is actually going to be an N-Trak module, just to get my feet wet in the hobby) actually seems pretty dead set on everyone using DigiTrax, so I will be cobbling together an extremely basic DigiTrax system for that. You do bring up some other valid points, though. Vendors have, as I understand it, in fact extended the functionality of DCC beyond the NMRA specification. However (and correct me, if I'm wrong here) only a small set of information is available for communication from the loco module back to the command station. Just using RailPro as a wireless example, that two-way communication is virtually unlimited. Any information you can see on your throttle can be reported from the loco (speed, location, load voltage and current and managed and reflected in the throttle UI in real time. The Z21 system is the closest I've seen any DCC system come to achieving that.

This may simply boil down to a couple decisions on my part:

• Is the unsurpassed consisting system of RailPro something I can live without? Honestly, if DCC could manage such an effective load sharing implementation, we wouldn't be having this discussion.
  
• How confident am I in the future growth and viability of DCC? It's been around 20+ years and is just now starting to scratch the surface of some of the features RailPro offered right out of the gate. Is that the DCC ecosystem just finding a way to push DCC past it's limits, or has innovation just moved at a snail's pace all these years, and vendors are just now deciding they should start flexing DCC's muscles a bit? The research I've done seems to point to the former.

I'm finding this discussion quite helpful. Thanks again.

 

Rich,

I think you have a good handle on this and I don't disagree with your reasoning. As will most consensus driven standards, DCC is not evolving quickly enough for the adopters needs. Lenz released their Railcom technology to the NMRA DCC working committee way back in 2000 to help aid them in creating their two way comms specification. This I am sure is meeting resistance from other rival manufacturers giving credence to you view about the speed of development of DCC. I have seen a similar thin happen in the electricity industry when they tried to pull together power producers and retailers to enable the transmission of power across continental America. Eventually, the equivalent to NMRA in the power industry, EPRI, had to bring in consultants to resolve the deadlock. I am guessing NMRA are not likely to do likewise, hence here we are 16-years later!

One day they will make a decision.... we hope.

Russ.

 

oops the board glitched!

Russ.

 

I'm curious what system people reading this thread would choose, were they in my shoes and just starting out, completely new to the hobby. Would you go with the aging industry standard, DCC, or would you embrace something new and less proven, that provides useful features and functionality not previously available? I can certainly understand those who would shy away from a proprietary system, for obvious reasons, but if it just works...

 

It has been 45 years since I ran my Hornby HO DC system in the UK. I came back only a month ago, prompted by my wife, and I can say I went for DCC. Why? It seemed to me, being rather new, that DCC gave me what I wanted, more than one train running without the need for the block management I remember. Being a computer geek I also look to use the computer interface for a fully automated system.

I am sure others have their own reasons for choosing what they select. This discussion has extended my view and for that I thank you.

May be others will chime in on their thoughts.

 

Keep in mind that DCC is severely bandwidth limited compared to Bluetooth or Wi-Fi and the signals coming back to the controller are even more limited. DCC also depends or the constantly changing characteristics of the track, wheel-pickups, ... If it were even a decent communication path we would not have so much complexity in the setting of CV’s. There is already one DBTC system being sold by a major manufacturer.
Bob

 

I may not have made it clear, but my only use of N-scale would be with a local N-Trak club, and I would be ok using a minimal DigiTrak system for my N-Trak modules, as it is a club requirement. Sure, it's an added expense, but even if I do decide to go the DCC route for my HO home layout, I would favor the Z21 over DigiTrax.

 

Yeah, I'm coming to understand that. However, when corresponding with the club president, I first asked what they used. He replied, "We use DigiTrax." When I inquired further about the possibility of perhaps going with another DCC brand, the response was, "We use DigiTrax. You can use whatever you want on your home layout. If you want to be able to run your trains at club events, you will need a DT402 or UT4 throttle." I let it go at that. I'm the new guy and have no interest in making waves, so I will conform...for my N-Trak module(s), anyway. So I end up having to buy a used DT throttle and learn how to use it - not necessarily a bad thing.

 

Why not try Sprog with JMRI and wi-throttle? Takes minutes to set up, you have wireless control and anyone with a tablet or smart phone can run a train?
1)wi throttle and jmri are free.
2)a sprog system is about $100
3)All you need is a desktop or laptop and a router.

Sent from my SM-G920P using Tapatalk

 

What would I use if starting out today? Not a single answer to that one, I would consider what the layout required and maybe have more than one system and budget would have some bearing.

For a small layout that little ones would use it would be the Bachmann E-Z Command. There is nothing easier for beginners to use with pictures of the trains by the buttons for quick and simple selection. Even if money was no object I would choose this - it is just the best for the job and stands up well to exhibition use (you see a lot of them in exhibition use here in the UK) and they are cheap enough you can have a spare.

For large scale out of doors where there would be room for the batteries I would probably go for a radio control solution. Unlikely to be Bluetooth based where the range would not be adequate.

For everything else it would either be an all-singing all-dancing console type system with colour screen and Ethernet/Wi-Fi connected like perhaps the ESU Ecos or some better systems that are coming along with integrated JMRI and Wi-Fi if the budget allowed, or if not something like a Sprog or Z21 that I can attach to a computer to achieve the same thing all be it not as neat.

Suzie x

 

As for bandwidth and such, controlling trains does not actually need very much, and for the average modeller the bandwidth over the track is more than adequate. There are plenty of systems in place in the specification to ensure that the bandwidth is used wisely to ensure timely communications to anything moving on the track. Modern components that were not around when NMRA DCC was invented are now here, and being used, so that feedback from the trains in the form of NMRA feedback (Railcom), or the proprietary Digitrax Transponding are available in most recent systems and decoders. Better quality decoders are also able to reject track noise and far exceed the minimum specification to extract data from the track (watch the Youtube videos of Lenz fitted trains driving over paper on the track and still decoding the data!)

The issue with radio systems and security is not so much whether you need it or not, but that you get it anyway whether you like it of not and regardless of the fact that you are only transmitting and receiving a small amount of data back and forth to the trains a lot of data overhead has to be shipped to encapsulate the payload data so as well as requiring more bandwidth there is the latency of encrypting and decrypting to do as well. Add to that infrastructure based environments like Wi-Fi where data goes via a router where everything has to go in and out again on the same channel doubling the data it all starts to add up.

Having multiple unconnected systems in the same physical area does all share the same bandwidth. There is only one Bluetooth channel, so if you have two Bluetooth devices both will operate at half speed if in use at the same time. Get ten devices and each will operate at a tenth the speed and so on. It does not make any difference that the systems are not connected - they will still to some extent co-operate to share bandwidth (if they did not it would all grind to a halt!). As distance from transmitter to receiver increases the system will adapt to the reducing signal to noise ratio and use increasingly more robust data transmission that further reduces bandwidth. It all adds up so you will never see anywhere near the advertised headline bandwidth and in the end have bandwidth more in line with what is on the DCC track but with added latency. Wi-Fi is similar with only three distinct channels available on the most popular 2.4GHz band and all are shared with Bluetooth. 5GHz has a lot more channels, uses a more robust and efficient transmission method (802.11a and 802.11n) and allows higher power transmission (1W rather than 100mW), but while equipment using this band is becoming more common, it is still quite thin on the ground and I am not aware of it being used in any model train control system yet.

You can all draw your own conclusions, there are swings and roundabouts (you can choose, they are different, but they should all be fun in the end!) but the regular command station to track interface is by far the most robust method to control trains and using good quality equipment installed following best practice you will find it completely reliable. How you connect to the command station makes the biggest difference in how you perceive DCC. Use a wireless app and you won't know that you are not directly controlling the train via wireless means. What data passes between the command station and mobile device has a significantly different traffic profile to the data between the command station and train and it is tailored for the communication medium in use (IP network) rather than DCC track interface (real time control). Even using suitable software like DecoderPro takes away a lot of the chore and mystery of CV programming on DCC.

Try things and see how you get on. After all potential problems are just that, they may not be problems for you, but they could happen at any time because we know the reasons that can cause them and some things are very hard to mitigate once they happen - and when they happen at the train show where radio spectrum is already heavily congested with the customers phones and tablets that is exactly where you don't want them to be happening.

Technology is changing all the time and new things come along, and with time mature to being something usable rather than flashy and different - but I always advise if you are doing something today use products that are available today that you know work well unless you are just experimenting. there is nothing more disillusioning than trying something and finding it does not work. Make your success and build on it!

Suzie x

 

Good things to consider, Suzie. Personally, I don't understand why a lot of people immediately jump to Bluetooth, when discussing wireless train control. I've used plenty of Bluetooth devices over the years, and none of them could ever hold a candle to standard wi-fi in terms of connection stability and bandwidth. I think it may just be a case of folks wanting to jump to the "latest tech", without considering use cases.

If you're at a public even and trying to access the internet from your phone, you're hitting a cell tower - the same tower everyone else is hitting. If you're connecting to your own router with its own IP address, you're the only one using it. Sure, the 2.4 and 5GHz channels are limited to some extent, but the TCP/IP protocol was designed to handle that. The communication messages used by a wireless system aren't going to be exponentially larger than those required by DCC, further simplifying the task of packet reception and transmission on the router. It's kind of a moot point, though, as I don't intend to be hauling my home layout anywhere.

And we can agree to disagree on which may be a "more robust" solution (Exhibit A: RailPro's dynamic load sharing).

I'm enjoying the discussion. Thanks.

Rich

 

Funny, I've been pushing on wifi and Ethernet as the system for years now, but then, I'm an electrical engineer working for one of the major Network Equipment manufactures. I'd love to see an updated standard and I'm no fan of Bluetooth.

Having said that, there's nothing wrong with the CAN bus that is DCC. It doesn't offer expansive feature, but it is well suited to the transmission medium and it's well supported.

What would I choose if starting over? DCC in a heartbeat. Sprog+jmri or possibly dcc+. As much as I'd like a wifi/Ethernet system, I like having a large selection of ready to go equipment and a wide variety of aftermarket options. The newer systems just don't have coverage. And I'd go sprog with jmri, because it's the most full featured and customizable.

 

The wide availability and variety of parts and equipment is certainly a positive for DCC.

Could you explain a bit further how Sprog and JMRI tend to me more full-featured than, say, DigiTrax or Z21? I've only briefly looked into Sprog, but it seems to basically do the same thing as other systems, only a bit less expensive - perhaps at the cost of some added complexity?

 

MRC (Model Rectifier Corp.) is now developing their wireless "Loco Genie" with DCC-like controls without the complexity of DCC. It uses radio signals for the wireless controller to communicate directly (not through the rails or a command station) with the onboard decoder.

An ordinary power supply is all you need. It will also work on DCC, AC, or dead rail layouts.

My layout is DC, and this is what I've been waiting for!

John