Hornby Elite DCC - some comments

And the BBC scripts, of he original radio shows. The first series matches the first book and the original TV series - after which they go in yet another direction.

Well, I was thinking about going DCC, but all this talk of low address and high address and will it or won't it is putting me off. I thought DCC was DCC was DCC. Isn't there supposed to be a standard for all this?

Nope, until it all works together to a common standard, I'll stick with plain old DC, methinks.

There are standards. Short addresses can be 1 - 127 and long addresses can be 1 - 10239. A bit in CV29 determines which type of address a decoder will respond to. It's not difficult to understand and any decoder that does not support this is not compliant with the relevant bits of the standards (long addressing is optional but must be implemented in full to be compliant).

When it comes to the user interface on the command station, some manufacturers have, however, chosen to interpret the standards in their own way and restrict users to, say, short adresses of 1 - 99 and long addresses of 100 - 9999. They call it "differentiating" their product. I call it deliberately confusing the user so that they stick to one manufacturer.

It does work to a common standard. Despite the confusion over addresses, any compliant decoder can be made to work with any compliant command station. At the same time, manufacturer specific features such as transponding are allowed to co-exist with plain vanilla DCC.

MBQ

"Paul Boyd" wrote

There really should be, and until there is universal compatibility and a genuine 'plug & play' option then I think it acceptance is likely to be held back.

I've heard today that Hornby may well go along the route of fitting a decoder to ALL of their locos. This I think will be a great mistake as firstly it will undoubtedly add to the retail price, and secondly is unlikely to be of a high enough spec to suit all DCC users.

There's also the issue of using chipped locos on analogue systems, where locos fitted with feedback decoders will not always operate satisfactorily with DC feedback controllers.

John.

Yes, there is, the NMRA Standards and Recommended Practices for DCC. Unfortunately, a number of manufacturers have decided they Know Better, and refuse to play nice. Hornby is one of these; Marklin is another. Note that both try to lock the buyer into their "systems", which is no longer a good marketing strategy. You either produce stuff that will play nice with other mfr's stuff, or you risk going under.

Actually, Hornby did go under, and so did Triang (who bought Hornby), and so did Lionel, and more recently Marklin did too. Serve them right IMO. The buyers of the Hornby marque seem poised to make the same mistakes as the original. Dumb, if you ask me. (Don't mind me, I'm feeling extra grumpy this morning.)

Stick with Lenz, Digitrax, NCE, Bachmann (limited, but standards-compatible), MRC, and even Atlas.

HTH

Even lenz don't play by the letter of the S&RPs restricting the user to Lenz's interpretation of short and long addresses (see my earlier post).

snipped-for-privacy@hotmail.com said the following on 21/11/2006 15:28:

Can I just turn it on and play trains? :-)

Hi Paul,

DCC is 10-year-old technology on its way out.

Sending control signals via a rolling contact is inherently unreliable, and the high-current square wave is not environmentally friendly.

Look at computer developments, and wait for the next generation of wireless controls using the track for power only -- not power + control signal.

regards,

Martin.

The key underlying standard is the protocol and packet format that every decoder, command station etc must comply to. As far as I can see the Hornby decoder and command station meet these but are restricted in what you can do with them which is price performance trade off. So pick the system that meets yours. A system is only non-compliant if it won't work with these protocols OMHO.

Chris

Granted, but ---

DCC is a software spec, not a hardware spec. NMRA does recommend wiring harness colours and format, so that any decoder can be plugged into any loco. IMO, the DCC spec is just as compatible with wireless signals as with rail-carried ones.

Evidence please!

That's why the protocol was designed to, and does, overcome the problems, very effectively.

Eh? If you mean EMC problems then say so. It has little to do with the environment in the normal sense of the word. Can you give any references to documented and verified cases (rather rthan urban myths) of DCC causing any problems?

The power pickup is still through your inherently unreliable rolling contact. Just look at DC.

Where will the antennae fit on the loco without looking hideous or preventing the use of tunnels?

How will it work when fitted to an O gauge brass or white metal loco without spending a fortune tuning the antenna system?

What qualifications do you have to be able pontificate on wireless DCC?

Just because you can buy a bluetooth earpiece for your mobile 'phone, it doesn't mean that it, or any similar technology, will be applied to model railways in a way that can produced economically for the mass market.

MBQ

Actually it is 30 year technology - Lenz patented if around 1978.

Rolling contact is inherently what we have in wheeled vehicles rolling on metal tracks. Possible alternatives are;

- self-contained battery power, which is more expensive and often not practical.

- power transmission by induction, with potential health hazzards.

That's a problem of 30 year old technology - more environmentally friendly wave forms are now practical.

It seems to me that we're doing quite well with power + control signal through the track and that there are more than enough signals floating through the air already.

Regards, Greg.P.

The short address of those decoders probably is 3. The other system will have set the long address to some greater value, but the Compact doesn't read that. The decoder won't run with a Compact until you have programmed a new address which will probably also flip the bit in CV29 which selects between long and short addresses. Note that the Compact can program any CV regardless of what the address is set to (even if set to a long address which is obviously outside the Compact's address range).

"Greg Procter" wrote

So when did Hornby's Zero 1 come into being?

John.

Airfix had a system around then as well.

No, NMRA is based on Lenz technology.

wrote

I didn't say it wasn't, but I thought that Hornby had instigated the basis of DCC (whether they patented it or not) and that it was later developed by others into a really workable system.

John.

Hang on Reverse Polish Notation is (or was) part of computer science, not from fiction. I remember it well, it was invented by a Pole, about boolean algebra and .... hads lots of NOTs in.

Simon

I totally agree, we're not using anything until its defined by a common standard !

Erm.. What shall we do about wheels ?

Simon