Digitrains has been trading for nearly 15 years from its Lincolnshire base. You meet them at exhibitions up and down the country and most importantly, they are helpful people. The BRM team caught up with Nicole Fairlie-Smith, director at Digitrains, to find out more about DCC and to help dispel some of the myths about the technology.
BRM: Where should people start with DCC? It all looks so complicated.
Nicole: The first thing we ask when someone comes in to the shop, is why they want to go DCC? Are they unhappy with their layout? A lot of the time they don't really know and are content with what they have already, so we say there is no need to change. We aren't twisting people's arms to go DCC. An often misconception modellers have is that only DCC locomotives are available. People see ‘DCC-ready’ on a box and assume that this means they have no choice and have to go DCC. That's not true.
BRM: What is the advantage of DCC?
Nicole: It's basically what we call a ‘drive anywhere, park anywhere’ system. All your track is powered and you have access to anywhere on the layout with any of the locomotives at any time. You don't have to worry about where the electricity is. So long as the points are set, you can drive. You can have a shunter working in a siding, a locomotive going around on the main line and something else on a second line idling with lights and sound.
BRM: Are people nervous about changing?
Nicole: Oh yes, but once you explain the basics, they tend to relax a bit. Most seem to think that because it's digital, it's going to involve using a computer. If you love computers, you can connect one up to automate your layout, but you don't have to go anywhere near one if you don’t want to.
BRM: I already have a layout. Would I need to rewire it to convert to DCC?
Nicole: Not at all. All you do is replace the DC controller with the DCC version – the same two wires feed the track and everything will work. If your control panel has isolating switches on it, make sure all these are in the ‘on’ position as you want the electricity to get to the whole of your track. After that, you have a digital layout.
BRM: Does this simplify the wiring?
Nicole: Yes. There's no need for those isolating sections. Everything is controlled from two wires. However, we recommend running a ‘track bus’ - a ring main around the layout and putting connections to the track from this in several places. This is really easy though, and no different from DC where you also need to make sure the track is fed from many places to ensure everything works. It's just easier with DCC. We've wired our test track up this way using copper tape on the board surface so people can see what is going on.
BRM: What about points?
Nicole: The thing with pointwork is that when DCC came out, people were running older models with thicker wheels and tighter back-to-backs. On these, it is just possible for the back of the flange to touch the switch blade as it runs through and cause a short. Nowadays this is rare because of better wheels and points. We don't recommend hacking points and we never make changes. A lot of people only do this because they have been told to do it, and don't really understand why.
BRM: Looking at adverts in magazines, we see the phrases ‘DCC-ready’ and ‘DCC-compatible’. What do they mean?
Nicole: ‘DCC-ready’ and ‘DCC-compatible’ are almost the same thing. ‘DCC-ready’ means the model has a socket ready for a decoder and there is space for it. Some older models can be absolutely chock full of chassis, so fitting a chip is a major job. ‘DCC-ready’ means the designer has made sure space isn't a problem. ‘DCC-compatible’ means perhaps no socket is fitted but it’s easily accessible with labelled solder points enabling chips to be wired easily. ‘DCC-fitted’ or ‘DCC-onboard’ are locomotives already fitted with DCC decoders.
BRM: Will some DCC locomotives will also work on analogue DC?
Nicole: They will, yes. Some are arriving from the factory ready so it can run on both, but others need to be setup to tell it to work on DC. If you aren't sure, ask the person selling you the model or check the manufacturer’s website for information. Most can work on both.
BRM: How do you choose the best DCC controller from the dozens out there?
Nicole: We interrogate them, or at least ask a series of questions; the first of which is, how many locomotives will be on the track at the same time? Some controllers provide more power than others. For example, the NCE Powercab is 2A, Digitrax Zephyr Extra is 3A, and we have some that will provide 6A. If you are only running two N gauge locomotives, the high-power system won't be essential. We also ask if they prefer a console system or a hand-held controller. On the whole, people prefer hand-helds as they can walk around, and you don't lose the space on the layout required for a console.
BRM: It's all about ergonomics then? So, you really need to try a few handsets before you settle on one?
Nicole: We tend to find that if people use a handset they don't like, they won't use it very often and then decide that DCC is bad.
BRM: Of course, it helps if you can visit somewhere that offers a full range.
Nicole: Yes, but if you visit an exhibition, take a look at the layouts and see what they are using. Ask the operators how they are getting on with their system, if they like it and if they wish they had bought anything different. These are tools to enable you to drive your locomotives. People at shows are always happy to chat and explain, if it's quiet they might even let you try them out. It's also worth chatting to your friends to see what they're using. If you run on other people's layouts, identical control systems might be a good idea.
BRM: Will all the controllers operate all types of decoder?
Nicole: Mostly. Some, like the Gaugemaster Prodigy Express, Bachmann EZ Command, Dynamis or Hornby Select don't have 28 functions, so you might not be able to operate all the sounds on some locomotives. We always ask as it's important to future-proof your system so it will last you for years to come. Some can be upgraded, but not all. There's certainly no issue taking a locomotive to the railway club or to a friend’s track. Decoders will work on all controllers, even if you can't access all the functions.
BRM: One scary thing is the wide variety of decoders available. How do you make sure you get the right one?
Nicole: On the end or back of the box of a ‘DCC-ready’ model, there will be something to tell you which sort of decoder you need. If the box says you need a 6-pin decoder, that's what you buy. If it says, 8-pin, you'll need one of those. Simply buy the one that fits your budget – we sell non-sound decoders from £12 to £40. If it's not on the end of the box, then the manufacturer’s instruction sheet or website will be able to help. The brand of decoder is often down to personal preference. For example, some people will only buy TCS because they were the first they bought and so they like to stick with them.
BRM: Is there much difference between decoders now?
Nicole: There is some, but much less than there used to be. Our £12 budget range comes direct from China and we think they're great, we haven't had a problem with them. Some people think they won't be as good as a Zimo at £20 and admittedly with one of these you will be able to make your locomotive crawl so slowly you can hardly see it move. Mind you, one of our customers buys the budget ones by the bucket-full as he likes them so much.
BRM: Does the budget range offer all the features? What about sound?
Nicole: You can control lights, but not sound. The £12 decoders are ideal for those making their first attempt at fitting a decoder. If you really muck it up, you've not wasted much money. They can also be used just as lighting decoders.
BRM: Does the number of pins on a decoder make a difference?
Nicole: No, it doesn't make any difference. 6-pin and Next-18 pins are the smaller decoders and therefore tend to go into smaller locomotives. 8-pin and 21-pin decoders tend to be bigger and are more suited to OO and O gauge. More pins mean more functionality in theory, but we see 21-pin decoders in steam locomotives with no more than basic drive and lights. The socket the manufacturer chooses is the one that works best for them, not always based on the functions required.
BRM: So, are they the same?
Nicole: Graham Farish's N gauge 0-6-0T ‘Jinty’ needs a right-angled set of pins and there is a special decoder for that. Hornby's Peckett needs a 4-pin decoder and the only one of those is available from its spare parts department.
BRM: What's the most common problem people come to you with?
Nicole: “My decoder has stopped working and I don't know why. What have I done wrong?”
BRM: What's a decoder reset?
Nicole: Using your controller, you tell the decoder to revert to factory settings. When we say that, we mean as it left us, complete with sound. The important thing is that a factory reset won't lose the sound files, something a lot of people worry about. You can't actually reset it back to as it left the factory. It will revert the locomotive address back to the standard for a new decoder, but at least you can tell the reset has worked.
BRM: This brings us to ‘CVs’, something I've heard about, but don't know much about?
Nicole: CV stands for Configuration Variable. They are all the little packets of information on your decoder that you can alter. For example, if your locomotive has a really slow start and takes ages to get up to speed and you don't like this, you can alter the CV that controls inertia.
BRM: Will this be in the instruction book?
Nicole: It is in the instructions that come with the decoder.
BRM: Can you break a chip by messing with the CVs?
Nicole: No. You can always reset it.
BRM: Presumably you can do this with the locomotive sitting on the layout, but we've also heard of something called a programming track - is this length of track separate from the layout?
Nicole: Most controllers offer the option of programming on the layout or a programming track. One of the advantages of working off the layout is that the controller can interrogate the decoder and find out what individual CVs are set at. The other is that the signal will be sent at low power, the locomotive can't be driven then, but there's also no chance at all of damaging the decoder.
BRM: A separate yard of track for programming sounds like cheap insurance against damaging a chip.
Nicole: If you are going to fit your own decoders to locomotives, we would certainly recommend it.
BRM: Sound is a big reason to go digital, but it's another apparently complicated area.
Nicole: There are several ranges of sound decoders. Many are set up for American or Continental models and we do stock those types, but we specialise in UK sounds for locos. We stock LokSound and Zimo – which we can sell pre-loaded with the sounds requested. You ask for a ‘Black Five’ for example and we'll take a blank decoder and add the sound file.
BRM: Can you add the sound yourself?
Nicole: Yes, if you have the correct decoder programmer, bespoke to the brand of decoder, however it is more technical and not for beginners.
BRM: How difficult is fitting a chip?
Nicole: If the locomotive is ‘DCC-ready’, you just take the body off and plug the decoder into the socket. Older models require you to hard wire the unit and that means getting the soldering iron out. It's not difficult as the decoder only needs to use four of its seven or eight wires – the red and black wires in from the pickups and the orange and grey out to the motor – but a lot of people are nervous about this.
If you want sound, you need DCC. You can get sound from DC, but if you want proper control, DCC is essential. Diesels with lights? Again, digital makes sense. One area we are convinced with is the simplification of the wiring. Running a bus around the layout is simple and adding lots of power feeds from this is a doddle.
Even on a simple layout, digital would allow you to run more than one locomotive without having to consider where the electricity is flowing – you could just concentrate on where you want the trains to go. The process of converting to DCC isn't hard. It would pay to spend time talking to people at shows before spending money. Getting hands-on time with a controller is essential.