What does DCC do that TMCC & DCS do not?

Classic Toy Trains Forum
1

I know that DCC is an open standard developed by the NMRA. I also know that, like DCS, the signal is transmitted from the central station to the locmotovies over the rails by being impressed on the power. That is, there are no RF receivers like TMCC. And I know that DCC decoders are fairly standard, while the central stations aren’t.

So what exactly can you do with DCC that you can’t do with the other systems?

I’m not trying to start a “my system is better than your system” thing here. I’m just curious about what the differences are. And maybe find out why Lionel & MTH didn’t just adopt DCC for O scale.

Tony

2

In a word, nothing.

I’ve gotta run soon for my real train, which doesn’t use DCC, but I’d like to add my 2 cents here before I return on Monday.

I think it was a mistake not to standardize. 3-rail trains could have fit into the NMRA. IMO, 2 systems discourage cross-pollination. I may be the exception to the rule, but I tend to purchase all MTH because I don’t want to get another system (TMCC). Perhaps people who have TMCC think likewise in the reverse.

I do have a weakness, however, for liking Williams and running in conventional sometimes.

If I had to pick a system over again, I’d probably go with TMCC, not because it is any better but because I tend to like what Atlas is offering as well as Weaver.

I think there has been a feud for some time between MTH & Lionel; I don’t like to speculate on things I don’t have facts and figures for but that’s my assumption why there are 2 systems.

3

I’m more familiar with DCC than TMCC/DCS - having installed it in N scale engines - now there was a challenge… But the common standards allow different manufacturers to offer you different interfaces into the same sort of capabilities, and a scaled approach to these capabilities - upper end systems allow control of more decoders. Let’s see - the basics: every object to be controlled by the system needs a decoder; and you need a controller to ‘communicate’ with the decoders - you do this by sending the signals to the rails. I know you can run non-decoder equipped locos on DCC systems, but not many of them and not very well - their motors scream like little banshees. What’s available: individually programmable graded speed steps, sounds, lights, you can run decoder-equipped accessories too.

4

The answer may be AC track power vs DC track power. My understanding is that DCS is very close to DCC in the way that it operates. TMCC is a whole other animal.

This is why the 2 rail guys are so pissed off at Mike. They feel like he ripped them off by claiming the patents on existing technology that was left open deliberately.

http://www.trains.com/community/forum/topic.asp?TOPIC_ID=12207

The standardization question should have come along 20 years ago, before the horse really got out of the barn. It will be very difficult to reign in all of the manufacturers now. Maybe for couplers, wheels and track it could be done.

Feud between Lionel and MTH? I think all out war may be more like it!

This should get interesting!! Remember gang, be nice.[:)]

5

DCS will actually work using DC power- MTH is using DCS in their #1 gauge engines. The only thing is that you lose horn/whistle & bell sounds, because they are activated by a DC offset.

6

Will,

Do you really loose the whistle and bell sounds when operating DCS on DC current? DCS does not use the DC offset in command mode (when operating either PS-2 or TMCC (via Lionel Command Base)). DCS sends a data message in command mode. DCS only uses DC offset when running conventional (you select Track 1 or 2, then press bell or whistle and you get the DC offset). I have played with this while running a TMCC in command, a PS-2 in command, and a post-war Lionel on the same track at the same time.

7

RAK, I posted what I remember about the way the DCS system was supposed to work in # 1 gauge engines using DC power. I just re read the ad copy in the 2004 vol1 catalog, and you are correct, bells/whistles do work in COMMAND mode, even with DC power. However, they will NOT work in conventional control IF DC power is used. Bells & whistles will work if AC power is used in conventional or command. Sorry if I confused anybody with my poor memory[:)]

8

It’s not a matter of what it does as much as a matter of ‘where’. I am acquainted with the owner of Digitrax. I asked him if DCC would be compatible with three rail O. He resonded that he didn’t think his equipment was heavy duty enough for such (to him) big heavy trains. I think in order to use DCC you might have to reinvent the wheel by adapting it to three rail. Once it was installed it might not be compatible with TMCC and DCS equipped engines. Of course, what do I know? I have no background in electronics so this is just an opinion. Odd-d

9

Odd-d, the problem that your friend may have been talking about is related to handeling the amount of current needed to run the large motors that we use in O. The components commonly used to make the receivers are not rated for much more than an amp or two. There are some larger units made for 2 rail O use, but not as many as for lower current drawing HO and N models.

My understanding of the basic concept of ALL COMMAND CONTROL is that a coded signal is sent to a receiver in the engine. Each receiver is set for a different channel number, and “listens” for its number to be called and then reacts to the command following its number.

Its what happens after that basic function that can get confusing, because there are different methods of sending the signals, as well as different types of signals.

For everyone’s information DCC CAME FIRST. The theory was around as early as the mid 60’s, but it didn’t really make it to the marketplace until about 1980, when it was published in MR, in a series of articles about a product called CTC-16.

This product was designed for HO engines only!!! At the time this was just catching on I lived in Denver, and knew a couple of guys that had decided to give it a try. Every week, a group of people would get together and operate trains, alternating between their two home layouts.

When I say operate, I don’t mean RUN on loops, I mean realistic operation, fast clock, switching, making up trains, keeping to a schedule, point to point track plan, that kind of stuff.

I was always hearing about and seeing the latest updates, as these guys were running some of the first practical test layouts. On one occasion Keith Gutierrez, the author and designer of CTC-16 visited one of our operating sessions. They were both in constant contact with him, and always got some of the first new designs to test.

I never realized until just now that I was a witness to history.