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This thread is for discussion of implentation, Hacks and Mods to NMRA-DCC compliant digital command control systems for use in the slot car environment.

The National Model Railroad Association (NMRA) is the governing body for the Digital Command Control (DCC) protocols used in model railroading to transmit digital control signals through the railroad tracks to the locomotives. It is a noisy environment that frequently experiences loss of signal due to gaps in the track or buildup of dust and other non-conductive elements on the rails.

Initial investigations show the DCC specification is sufficient in all ways to be used as a slot car digital control system. Early experiments by slot car owners are showing this to be true in practice.

In this thread we can discuss the products that are available, how they can be adapted for slot car use, Hacks and Modifications for specialized purposes, and our experiences when using them.
 

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great first post mr cool, welcome, and thanks for the interesting insights!

Totally agree that a open or licenced system from one of the manufacturers would be the ideal, and think it may/will be in the future.

Since the intricacies of digital for slot cars is apparently much more complex than for trains (higher speeds, making sure following cars don't swap lanes, possibilities of anti collission systems, telemetry, fuel and weather simulations etc) - it is perhaps beneficial that there is initially competition to be the best system, to make keep the various players working hard and on their toes!

(although in the VHS/betamax video war, the worse technology won!)

[edit: the following bit is a reply to part of MCZ's original first post on the scalex digital thread where he detailed choosing Carrera digital system over Scalextric due to the vast differences in customer services he recieved. In moving this thread to a better place, that bit seems to have dissappeared, but continues in future posts!]
I can understand your reasons for choosing not to go for scalextric, however I can also understand scalextric wishing to keep developement of a new product confidential. If you had been choosing your purchase next year, the issues which have swayed you would not have come into play.

Cheers and hope to see more of your thoughts on the forum in future!
 

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QUOTE (My Cool Zoommacher @ 15 Jul 2004, 19:33)I hope we see that day arrive in slot car racing, and I believe in it with such conviction that I'm starting research on how to apply DCC controllers and receivers to the slot car world. If receivers can be made that fit in a N-scale (1:160) locomotive, control its speed (regulating it uphill and downhill if you choose), use acceleration and braking curves, control lights, and make decent, realistic sounds... certainly something can be designed for a 1:32 slot car.
Welcome - and to answer the "Does Model Railroad DCC work with slot cars?" in a word.

Yes

I have a 70ft routed track, utilizing Digitrax DCC with 4 UT1 utility cabs for control.
Works like a dream.

HO decoders are ok, with Z scale being the best fit.

QUOTE (My Cool Zoommacher @ 15 Jul 2004, 19:33)I love digital control... if I couldn't buy the Carrera set I'd put in off-the-shelf DCC and live with "train-style controllers". Digital is THAT nice to use. I'm sure that the slot car world will enjoy this same pleasure in the near future, but I believe the key to success is standardization.

The reason I went with model railroad DCC was to be able to take advantage from the standardization.

Besides, if ever I get back into model railroading, I can use the Digitrax setup on non-slot car days...
 

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QUOTE (astro @ 15 Jul 2004, 19:59)Since the intricacies of digital for slot cars is apparently much more complex than for trains (higher speeds, making sure following cars don't swap lanes, possibilities of anti collission systems, telemetry, fuel and weather simulations etc) -
I don't think that is accurate assesment - railroading with DCC is just as complex, if not more so - than slot car controlling.

There are many calls for and use of very complex control and management options using DCC to simulate real world railrading.

Just because trains don't lap at 4800mph doesn't mean that a DCC system with 20+ active locos, and train detection and transponding features and location and detection and schedule control, signal detection etc is any less complex or responsive than what cars need..


Digital control is digital control - you simply have constant power to all the decoders (stationary and mobile) at once - and address specific commands to specific target decoders --- and what you do with these commands is the power and versatility -
 

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Astro,

from the little I know about DCC (and a friend of mine is one of Italy's top implementators) I'm afraid I have to agree with RC54 - railroads are light-years ahead

But what I found most interesting about MCZ's post was the attitude : here's a guy who's not afraid of actually telling manufacturers what he wants and expecting an adequate reply (it doesn't really matter if I disagree with his conclusions)!
Compare that to the customary kowtowing over the Nth livery....

Yes, what strikes anybody getting into or coming back to slots is the passivity of today's average Mr. Joe Slotracer - this explains why the time isn't ripe yet for bottom-up standards - one has to accept this reality, deal with it and little by little alter it... but I'm optimistic

Ciao
Beppe
 

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MCZ - Your track planner looks good

It does sound like the questions you asked scalextric (like about ferrari) could be considered sensitive and confidential - for example if they are engaged in delicte negotiations with some of the parties. But besides that - the fact of the matter is you judging customer services on one initial exchange. You were lucky enough to get off on the right foot with carrera and happen to get in touch with some helpful people. This is not proof that everyone does.

RC45 - I didn't mean to make out rail digital was in anyway more primitive or inferior to slot digital, I have supposed it was very sophisticated and developed by now.

Also your adaptation of it for slot racing is very convincing proof for the rest of your argument, but is hard to judge whether using a system honed for one application would eventually be limited when used in another adaptation. As you say, it facilitates 100s of trains, you will never need that with cars. Thats not a weakness, but maybe there are some...
 

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Now for some DCC talk. I'm personally excited at the opportunity presented in slot cars - and I was surprised it hasn't already migrated to slot cars. I gotta tell you I got a big smile when I read RC45's post! I'm not the only guy who sees the very natural fit of DCC into slot cars!!!

QUOTE Since the intricacies of digital for slot cars is apparently much more complex than for trains (higher speeds, making sure following cars don't swap lanes, possibilities of anti collission systems, telemetry, fuel and weather simulations etc) - it is perhaps beneficial that there is initially competition to be the best system, to make keep the various players working hard and on their toes!

Let's look at this carefully. Beppe has a friend working with DCC... I do, also. He has been writing DCC receiver firmware for the 7 years we've been friends. We've had talks about implementation when he was stuck... I remember when he was doing the code for using back-EMF to keep speed constant on grades.
That was non-trivial. Remember, he's trying to do back-EMF sensing and calculation at the same time the processor is generating the Pulse Width Modulation waveform that controls the motor speed. The timing issues were pretty complex... but the point is...

These processors are so VERY FAST that they are generating the rising and falling edge of the waveform in microsecond increments. From the standpoint of the CPU, the difference in speed between slot cars and trains is irrelevant.

Anti-collision? That's up to the driver.
Telemetry? There are track sensors, both magnetic and optical, used in model RRs as we speak. Fuel and weather sim? Piece of cake... done in the controller, not the receiver, where the real-time demands are much lower. On top of that, many DCC controllers allow a computer to control them, adding yet another CPU of processing power to coordinate even higher-level decisions to make the race more realistic and interesting.

Technically, there's no problem... as RC45 found out.

QUOTE But what I found most interesting about MCZ's post was the attitude : here's a guy who's not afraid of actually telling manufacturers what he wants and expecting an adequate reply.
That's a fact. We should ALL be like this. Look at this thread... look at the lack of data people can obtain... look how everyone is sitting here looking at pictures of boxes trying to guess what's going to happen when, and what it might do, and whether they should even be waiting for it. If all hobbyists took this attitude, the mfrs would remember an old Digital Equipment Corporation (DEC) phrase: CARE - Customers Are the Reason for Everything. We are! We should take our business to the companies that take care of us.

QUOTE this explains why the time isn't ripe yet for bottom-up standards - one has to accept this reality, deal with it and little by little alter it
The time IS ripe. This forum is filled with slotheads that have treasured collections, and they've been ignored by 2 out of 3 vendors. Look at the racing clubs in Europe - slotheads are a big community there, and buy LOTS of product. That will probably come to America as those of us who enjoyed slot cars as kids re-enter the hobby with 21st Century expectations (like me). I do not accept proprietary solutions as reality. They stifle the growth of digital control, rather than promote it. If you doubt it... look at the trouble you all have had making a decision between the three. None of them are JUST RIGHT for everyone's needs. Standardization brings interoperability, and that brings the promise of being able to buy exactly what you want for your own use.

I'll stop quoting now. Everyone has made very interesting and useful posts, and I acknowledge them all.

What I see is a market opportunity. DCC is so well-developed it would astonish those who aren't aware of it. The number of control variables is so extensive you could literally set it up for slot cars right now - as RC45 did. What we need is some throttles that are appropriate, and the overall "course management" functions such as pitRow/refueling, real pace-car control (that doesn't leave it in pit row), weather simulation... the kind of high-level functions that are different from model railroading. The fact is, the whole technical infrastructure for the most difficult part, the motor control, and transmission/reception of signals, exists today and is fully tested and matured.

I simply cannot understand why companies would choose to do ground-up development of a digital control system, with all its expenses and time-to-develop. They could have approached Lenz, Digitrax, Zimo... a dozen vendors could have made a cross-licensing agreement with slot car manufacturers. We could have been running digital for years, literally.

So, RC45... the primary concern over using controllers smaller than HO scale was current draw. In his case, the limiting factor is the rectifier, with its voltage drops across the diodes. The back-end is MOSFET - very low resistance, and capable of the 0.5A current we are estimating is typical for slot cars. But if the slot car motor drew 1.0A, that's pushing the limits of the rectifier in N-scale decoders.

Are you having any difficulties with overheating? Have you lost any DCC receivers after driving hard for a while? If not... that's great news. And did you really mean Z-scale??? Those are for the Maerklin products, they are SOOooo tiny I'm quite surprised they work. If you tell me they're N-scale, I won't be surprised... but if Z-scale actually works, that means we can look forward to controlling literally ANY 1:32 slot car!

In summary: we, the hobbyists, the users, the ones with the money... we have an alternative in DCC. As RC45 did, we can go with hand controllers that aren't exactly what we like for racing, and the solution is off-the-shelf. If we want a nice pistol grip (that doesn't look like Federation-issue
), "we" can manufacture it. In this case, "we" might be "me", and when I read all your thoughtful postings I grew even more excited about the opportunity.

Once the throttles are made, the rest is software. All the "cool stuff" like pace cars and refueling and weather are high-level functions that have only a small coupling to the vehicle control functions... tweaking a control setting here and there in response to diminished fuel or wet roads. There are times I think such a product could be introduced before Scalextric's product, except for the lead time of the pistol grip. Gosh, even there, if "we" could OEM a pistol grip and just make an interface module between it (them) and the DCC control unit, THAT job would be minimized as well.

I think this line of thinking makes sense. I don't see anyone happy with any of the 3 vendor's offerings. I see a fully developed DCC technology that we can count on to be reliable - it has almost a decade of experience under its belt.

On top of all that, it's a way for The People to speak. We do not have to sit here and let them tell us what and how we get to race. We can take the matter into our own hands, come up with something REALLY good, and have the confidence and interoperability of a standard to let us feel good about spending the money to go digital.
 

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dcc does sound like a good solution, but then again if enthusiasts use that - there will be 6 digital systems competing! (SCX, carrera, scalextric, ninco, DAVIC, DCC)

I think standardisation will only take place if one of these gains massive club AND home dominance. And I think one (eventual) universal standard will be better for the hobby than the technically best solution, as long as the standard chosen is adequate.
 

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QUOTE dcc does sound like a good solution, but then again if enthusiasts use that - there will be 6 digital systems competing! (SCX, carrera, scalextric, ninco, DAVIC, DCC)
This is exactly what was going on in MRR 10-15 years ago. It doesn't take long to figure out that standardization is the only solution, because then those first five would all work together for the benefit of all of us. In fact, the best time to stop the proprietary growth is right now, before anyone gets market momentum and tries to impose their solution as the standard.

QUOTE I think standardisation will only take place if one of these gains massive club AND home dominance.
This needs to be prevented. The MRR industry went nuts for a while because the Lenz system was chosen as the standard, which further delayed its acceptance. DCC technology is wholly adequate for everything we want to do in slot cars, refined by hundreds of thousands of users who are as demanding of their hobby as any of us are.

QUOTE And I think one (eventual) universal standard will be better for the hobby than the technically best solution, as long as the standard chosen is adequate.
And the good news is that the standard exists today. The ONLY thing "wrong" is the throttle. RC45 has proved it, and I'll be buying an analog Evolution set so I can do my own experimentation. Open architecture lets the individual creativity of everyone emerge.
 

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QUOTE So, RC45... Christoph's primary concern over using controllers smaller than HO scale was current draw. In his case, the limiting factor is the rectifier, with its voltage drops across the diodes. The back-end is MOSFET - very low resistance, and capable of the 0.5A current we are estimating is typical for slot cars. But if the slot car motor drew 1.0A, that's pushing the limits of the rectifier in N-scale decoders.
This was my concern and as such I chose Digitrax DZ123 1 amp/2 amp peak current rating decoders.

I used a couple HO DH123 1.5 amp/2.0 amp peak decoders as well.

QUOTE Are you having any difficulties with overheating? Have you lost any DCC receivers after driving hard for a while? If not... that's great news. And did you really mean Z-scale??? Those are for the Maerklin products, they are SOOooo tiny I'm quite surprised they work. If you tell me they're N-scale, I won't be surprised... but if Z-scale actually works, that means we can look forward to controlling literally ANY 1:32 slot car!
Well - what good is being on the "bleeding" edge if you are not willing to spill some blood..


Do you like your digital decoders fried or baked?

The first decoder self-destructed when the SCX Evo 4wd diffs began to bind a little, and I am guessing the constant extra current being drawn by the labouring motor was just too much after a time... and the 2nd one I am not to sur - as the car it was in (new AutoArt Lamborghini Murcielago) was only running for a short time and this was the result.

The current decoder has held out pretty well.

While the HO decoders are small, there is really not much room in full-interior 1/32 cars - and the Z scale Digitrax decoders are ideal.

I wonder how much attention Digitrax would be willing to give to the slot car side of things.

I spoke to both Digitrax and Soundtrax over the phone one day, about what I was doing with regard to retro-fitting railroad DCC in slot cars, and the interest was more academic that anything else.

Perhaps if an "industry insider" was to approach them, a different response would be forth coming.

As an aside I have been using 3rd Planit for a while...


-Paul
 

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MCZ, is your name Dennis Miller?


We get your point. It seems that Scalextric have no hope now


Being constructive: What about steps to introduce a Digital standard for slot cars? We have 6 manufacturers that don't talk to each other much and the making for a bloody battle over the next year or two.

Why don't we offer an independent forum of discussion to lay the foundations for the standard. We get the experts on board, we have the fanatics already and quite a few experts amongst them too. We bring in some train gurus who can educate us about the lessons learnt and move on from there.

We're looking for the blueprint - not implementation, but just a standard for others to use.

We offer the standard to the manufacturers and see who bites. If it's good enough they couldn't refuse.
 

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QUOTE (astro @ 16 Jul 2004, 01:22)A DCC thread would be brilliant

There is an entire Digital forum... ??


BTW - DCC is a reference to the technology in general, not a product.

DCC - Digital Command Control.

Digitrax (what I chose) is one vendors interpretation of the Lenz-based standards that the NMRA (National Model railroad Association) ratified.

 

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QUOTE (Nuro @ 16 Jul 2004, 01:26)We offer the standard to the manufacturers and see who bites. If it's good enough they couldn't refuse.
Who will "police" and manage these standards and adherance to them wiht regard to carrying "logo support"?

Slotcars need an overseeing association first....
 

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QUOTE Do you like your digital decoders fried or baked?
Baked, thank you! Some corn and potatoes would be welcome, too!

Would you mind unwrapping that top one and take a picture (tight zoom) of the failing area? Try to get the part numbers in focus so we can identify the failing component. I happen to have a different brand of DCC.

QUOTE The first decoder self-destructed when the SCX Evo 4wd diffs began to bind a little, and I am guessing the constant extra current being drawn by the labouring motor was just too much after a time...

You're correct. That was our projected failure situation... although I want to verify it with the photograph. For us "bleeders" this is OK, but for the industry in general it is not.

Controllers continue to shrink in size, and that's being led in Europe where N- and Z-scale are more comming than here, where HO dominates. When we did the calcs on a N-scale decoder, even under a full-stall condition, the rectifier should be able to deal with it.

We also noted that the same circuitry that provides the back-EMF information would allow us to recognize a near- to full-stall condition and cut off the current.

QUOTE I spoke to both Digitrax and Soundtrax over the phone one day, about what I was doing with regard to retro-fitting railroad DCC in slot cars, and the interest was more academic that anything else.

Judging by the time of day, you're in America. It's just not the same here, either in slots or in trains. Digitrax is the market leader, and they're busy doing their thing, oblivious to (or choosing to disregard) the slot market.

But that's the beauty of DCC... we don't need anything from the manufacturers. They supply the hardware we need, and all the software for basic use. I'd like a pistol-grip throttle, sure, but nothing more is necessary to be Slot Cool. To go to the next level - fuel, pace-car, and weather sim - as it stands now, it would require a computer or palm device talking to the DCC controller. This is possible, of course, but it limits the market to the more geeky among us.

But still, that's how snowballs start rolling downhill and getting big. As soon as the mfr's see enough posts of Geek Hack solutions to slot car specializations, they'll see the market and we'll see features coming from them. Someone wrote earlier about the "risk" of entering a market. He's right. But if "we" do all this, and then "we" start using computers and palms to make things really cool, the risk factor will be much lower because the market need has been established.
 

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Discussion Starter · #17 ·
QUOTE Who will "police" and manage these standards and adherance to them wiht regard to carrying "logo support"?

Right now, the answer is: NMRA and you might also like to read DCC info

This is a model RR organization of course, but that doesn't matter really. The DCC standard has a working committee that expands it as required, and certification for systems to prove they meet the standard.

All the crucial variables needed for slots are already being policed. They are sufficient for our requirements. Throttles might be a niche market for a while, but it is just a speed bump, not an obstacle.

Higher-level features (fuel/wx sim) are not standardized; they are viewed as the inventive domain of the manufacturers. We'd be ad-hoc for a while, or these would remain open if that's the right solution.
 

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QUOTE MCZ, is your name Dennis Miller?
Nope. The name was italicized... as thought it has significance. I'm afraid I don't watch TV or keep up with today's ever-so-delightful news headlines, so if he's someone famous I probably don't know him.
 

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oh - and some things that might be slot car related issues not dealt with by the railway implimentation of DCC - braid to rail noise and interruptions of signal. The optimum frequency of digital signals will be limited by the chips and also the conductors of the signals. A train-wheel to track interface is different from a braid against track, and hopefully the slot system will eventually cover bouncy RAID 4 x 4s as well as le mans racers, will cover warped plastic sections set up on carpet etc etc.

Yes the choices made by the rail committees might work perfectly (indeed, they may even work better than those chosen by the slot companies!!!), but this will be by luck, not design. Large scale testing of any system is required to see how it works in the real world, as opposed to how it works on a handful of smooth routed tracks.

Nevertheless, your work and investigations are admirable and may be the future!
 
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