DCC Upgrade & Used

I've found the DCC discussions interesting. I'm also intrigued by the numerous advances in technology, such as with stationary decoders, sound, etc., which leads me to a couple of questions.

First, while I understand the basic principle of DCC, but I'm still unclear whether the heart of the technology's control side resides in the controller, or in the power-supply infrastructure.

I know enough about the technology to know that one must install certain power supply equipment, jacks, etc., and that one uses a handheld controller (usually) to operate the trains. And, depending on the size of one's layout, more than one booster may be required.

Now, I've been more or less aware of the DCC manufacturers' introducing new products, chiefly decoders with bells and whistles (both figuratively and literally), new capabilities, handheld controllers with new functions as features, etc. This is where my question regarding the "heart" of the control-side of the technology comes in.

Let's suppose "Modeler Smith" decides to upgrade the DCC system on his layout to take advantage of the newest capabilities, so he strips out the old and installs the new. What does he do with the old? Puts it on the used market.

Now I come along, and looking for a bargain, see his used DCC system and decide to buy it, as I'm interested in it.

This leads to a couple of questions. First, do "whole," i.e., serviceable, DCC systems, come onto the used market and if so, how frequently? (I know...it's not like trading in a used car against a new one.) Would I be able, assuming everything is in working order, to hook it up and actually run trains, all else being equal? I'm all for keeping expenses down wherever I can, so if I can snag a functional DCC system for a fraction of what I would pay new, I'm all for it.

Next, warranty issues aside, what are the advantages in buying a new system, such as Digitrax's Zephyr, to name one example?

Incidentally, I would use DCC on an HO double-deck switching layout of about

50-60 aggregate square feet, which also features a branch line. There would be perhaps four engines at most on it at a given time, and the whole kit and caboodle would likely be one power district. I would use the simplest decoders on the market, as I don't need sound, nor the "special effects" so popular these days. Control and perhaps the headlights would be adequate. (Don't get me started on sound; I can recreate the sound effects in my head because I work on the railroad as it is.)

Dieter Zakas

P.S. Please forgive me is this doesn't seemed focused at times; after all, I was writing this at three in the morning. :-)

Reply to
Dieter Zakas
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Yes. ;)

First thing to keep in mind: From the rails to the train, it makes no difference which brand system you use. You can use any manufacturer's decoders on any DCC layout. Older design decoders may require setting the "status", but they WILL run.

Most DCC under-layout units actually have _two_ components in a single box: a command station, and a booster.

A "command station" generates the actual digital code that goes out to the trains on the tracks. There can only be ONE command station per layout. All communications between throttles and decoders go through the command station, and the capabilities of the system depend on the command station. It keeps track of how many throttles there are, which trains are assigned to them, what settings they have for functions and speed, and many other "bookkeeping" items. The command station also decides which signals are for the throttle(s) and which need to be passed on to the booster(s).

A "booster" amplifies the signals generated by the command station to the track levels. It also has some kind of short-circuit protection to shut itself off for a brief period if necessary, then automatically resets. A booster does _not_ talk to the throttles, or _generate_ DCC commands for the track. It simply relays the DCC commands from the command station and relays them to the track at higher power. (Yes, it's more technical than that, but that wasn't the question...)

A second booster ( in addition to the one in the command station) is _only_ necessary if the total power draw of the layout exceeds the capability of the booster. If you want to establish "power districts" for ease of troubleshooting or smoother operation (keeping that clown switching the industrial park from shutting the entire layout down every time he runs a turnout set against him, for example...) you just add a "power manager" of some kind.

_Most_ DCC units sold at hobby shops have BOTH a command station AND a booster in a single package. The command station establishes the capability of the system (number of trains that can be commanded, for example, which is fixed and not related to power requirements or scale). The Booster determines the electrical capacity of the system (amperage of the system, which determines the total number of trains that can be run, BUT is relative to scale and current draw).

It depends on what he bought. Some DCC systems are easily expandable, and even the most basic units can be expanded with most if not all the peripherals of the top of the line systems. In this case, it's not likely that they will sell anything.

On the other hand, someone who buys a system that is NOT upgradeable or expandable and is inherently limited probably WILL sell their old system... but it's not likely it's one YOU will want, either.

Yes, it does happen. You won't get their decoders, though, because they'll be usable with their new system.

You sometimes CAN get used decoders from someone who is _upgrading_ decoders to add new capabilities to their fleet, but if they're wired-in decoders you might have problems fitting them to you locomotives... they wires will have probably been trimmed.

Capacity of 10 trains, can use 2 old analog power packs as "jump" throttles so you can run three trains out of the box (2 require decoders), expandable to the full range of Digitrax throttles and accessories including infrared or radio/infrared wireless. 2.5 amp system, so that may be a limiting factor on how many locomotives you cn run. Can program AND read back decoders. Sounds perfect for your layout as described.

Reply to
Joe Ellis

Think of it as 'transformer/power supply/CPU/amplifier'. These four basic items can be housed in different combinations but the heart is always the CPU. In lineal terms the CPU of course sits to one side of the 'transformer/power supply/amplifier' sequence and feeds the amplifier to create a usable model railway power supply. The 'Booster' is a parallel 'transformer/power supply/amplifier' repeating the CPU signal.

All else sends information to the CPU and can either be system specific or comply with a standard communication format. There is nothing to stop manufacturers putting more smarts (a sub CPU) in any input peripheral item, such as a hans-held controller or decoder ands obviously many do.

Regards, Greg.P.

Reply to
Gregory Procter

In article snipped-for-privacy@news1.east.earthlink.net, Joe Ellis at snipped-for-privacy@mindspring.com wrote on 1/24/05 7:52:

I'm familiar with being able to use one manufacturer's decoders with another's DCC system.

For the layout I described (as yet unbuilt), making the whole thing one power district will probably work; I doubt, given the design of the upper level, that I will need a booster for it.

I wasn't looking for the decoders, necessarily, but an unwanted system that had been rendered "surplus."

So there IS a possibility I may be able to get some kind of DCC componentry on the used market. Excellent. Most locomotives today come with plug-in capability, so installing someone's used decoders is a possibility. However, for the number of older Athearn, and some Atlas, Kato and Stewart I have, they would have to be hard-wired.

I would probably "overbuy" my command station/booster component to provide sufficient capacity so I DON'T end up shutting down the layout...and plunging half the apartment complex into darkness. :-) Rather than a 5A booster, use, say, a 10A version, which is akin to an 8-cylinder engine versus a four-cylinder version. The 4-banger, while cheaper, won't have the power a V8 will, if you catch the analogy.

Elsewhere, I would stick with a tethered technology over the wireless version, especially for a switching layout. While I would opt for memory (as an eye toward the future when the switching layout is incorporated into a permanent home layout), I prefer the better response to a tethered connection over a wireless version, whether IR or radio. My club uses the Train Engineer Arito-Craft throttles on its DC-powered layout, and they're a PITA for switching. (Froggy will agree with me, heh, heh, heh.)

Joe, thanks for your reply.


Reply to
Dieter Zakas

on the used market.< There is some. Check ebay and just do a search on DCC.

8-cylinder engine versus a four-cylinder version.< Remember there are additional electronic parts that will subdivide the main booster output. One of the latest MRs had an article that explains this, probably the Jan. issue.
Reply to
Jon Miller

had been rendered "surplus."< An additional comment on used/surplus. One manufacture (actually importer) of really low cost sound decoders has them made in China. To save costs they have no QA done what-so-ever. There is a claim the failure rate is 25 to 30 percent. They charge a flat $15 to repair any decoder (probably more than _they_ pay for them). Bottom line, be careful what you buy used (or new for that matter). Example of a _quality company_; "All TCS decoders feature a Goof-Proof Warranty. One-year no-questions-asked replacement warranty, handled entirely by TCS"

Reply to
Jon Miller

in article BE1AB5E8.A800% snipped-for-privacy@enter.net, Dieter Zakas at snipped-for-privacy@enter.net wrote on 1/24/05 11:28 AM:

... Stuff deleted ...

Take care when "overbuying." Getting power to run many trains is a good thing as you noted. I use an 8 amp command stations (DCS200) and a 5 amp booster (DB150) so I never run out of overall power. BUT...

I've divided the layout into 7 power districts using PM42's set at 3 amps each for two reasons: a snort in one spot doesn't shut down everything and the PM42 lights tell me approximately where the trouble is.

And probably more importantly: a dead short, like running against a turnout, will only channel 15v*3amps (45watts) through the short for a short time; I've never seen anything even get warm. But 15V*8amps = 120 watts. Think about how hot a filament in a 100watt bulb gets and you can see how much heat is possible. If even for a short time, that's enough to melt or weld.

I suggest visiting the "wiring for DCC" web site (see below) for lots of information about protecting your layout when using these high power boosters.


Reply to
Edward A. Oates

There's a pretty good on-line DCC tutorial at:

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Bill McC.

Reply to
Bill McCutcheon

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