feedback controller and DCC

Absolutely, unless you have one of those Unimog type rubber tyred shunters - my prototype was very strict on locos following the rails! :-)

Regards, Greg.P.

Reply to
Gregory Procter
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Gee, I read all the books and I've fitted decoders to lots of locos. 8^{

What!!! Whyever not??? ;-)

My DCC CV programming is done via my computer - saves a lot of hastle.

Exactly - all those decoders empty the hobby budget account - I NEED more locos!!!

Crunch!!! I don't want to afford 50 decoders at once, nor do I want to limit operations to 10 or 20 locos.

I would by now be on my second or third upgrade of DCC central unit and second or third decoder upgrade programme. $$$$$$..... As it is, I still have a first generation central unit and first and second generation decoders on a few locos.

Regards, Greg.P.

Reply to
Gregory Procter

Depends on whether you are prototypically driving trains (individual loco control) or prototypically signalling them (prototypical route control). Actually with DCC you can do both anyway.

Reply to
Michael Walker

more intensive than a GWR single loco in steam branchline or a Big Boy hauling a train of fruit wagons across the desert you need block control of a layout.

Thats exactly the sort of reason why DCC was invented! So that you can easily operate trains without having to have blocks. Tell me what is prototypical about having blocks on a model railway, apart from the obvious signalling purposes. Even then there were so many exceptions it's not funny (station limits and banking locos for a start).

Absolute garbage. There are prewritten computer programs for both DC and DCC route control and signalling for a model railway. There is no need to write your own. As for non-prototypical, I might point out that DC is not particularly prototypical and to make it even vaguely prototypical you need to farnarkle around with blocks and power sections and isolation regions and if you really want prototypical operation for route control, then you'd include relays for interlocking and more electronics to make sure that nothing moves when it's not supposed to. Because I wanted to do all this without the electronics was the reason I went DCC in the first place!

I don't care that you think DCC is a waste of time Mr Procter, but if you're going to talk it down, at least be accurate and pick on it's true faults which at this stage is mainly the up front cost of the kit and the requirement for a decoder to be fitted in every loco you intend to run. In terms of "prototypical operation" either from a route control point of view or from the point of view of driving individual trains (something you think doesn't happen on the real thing based on your comments in this thread), DCC is a large improvement on increasing and decreasing power in sections of track.

To each their own, but I've seen fantastic layouts that are let down by complications in electronics in trying to achieve prototypical operation where DCC would be a major advantage in operation, the main inhibitor being the cost of conversion.

Reply to
Michael Walker

Same cost as your computer and some readily available software that probably cost the same as the time and cost of setting up all the electronics for a decent sized tradional layout (unless of course it is the traditional bench line terminus). Plus no soldering skills required (however, familiarity with a computer is required so I guess it's swings and roundabouts)

In my case they do: APT DMUs with the motor bogies in the middle (if I'm operating them in multiple) I also have a friend with quantities of London Underground stock made form kits and you'll never guess where he thought the best place to put the Black Beetle(s) was/were...

You're quite correct - YOUR prototype didn't place locos in the middle but there are plenty of examples where modelling expediency or the real thing did.

Reply to
Michael Walker

Only if you don't have any friends. Once a month I have four people come an operate on my layout. We drive a train each from one end to the other, dooing what is necessary with respect to shunting, meeting other trains, etc, on the way. At the end of the journey we are then rostered onto another train.

When I am by myself I run one train at a time, often running a train to in intermediate station, then moving to the other end of the layout and driving another train towards the first. That's fine for me, as my operations and preferences are "driver centric".

This argument is nothing more that the "signalman centric" oprtation versus the "driver centric" operation. Some people prefer one, others prefer the other. Some layouts are designed to support one form of operation, some the other.

Neither one is the only possible solution, and without knowing what a layout owner's preferences are, nobody can make pronouncements that DCC is the best way forward, or the DCC will not allow operation on his (undefined) layout.

John Dennis

Reply to
John Dennis

I'm prototypically driving trains by analogue control and I'm prototypically signalling them! :-)

Reply to
Gregory Procter

What more reason do you need to install signal blocks other than that the prototype uses them??? More to the point, signal blocks enable you to run multiple trains on the same main line, just like the prototype does. I know that with DCC you can run multiple trains on the same track in the manner that multiple cars/trucks can be driven on a motorway, but that's exactly where my analogy of slot cars comes in!

Well, you should be able to understand the reasons for those exceptions and deal with them/reproduce them in model form.

I'm not aware of any that operate as my prototype does and still allow for the compromises of model railway operation.

It's not the invisible bits I'm concerned about, it is the compromises the program forces me to make.

The only non-prototypical factor I need to farnarkle (lovely word!) around is uncouplers - they exist both in DC and DCC to the same degree and cause exactly the same compromises.

Sure, on this layout I've moved on from that point to including as much of the interlocking as possible in software form.

DCC doesn't provide any interlocking. The whole point of DCC is to provide a control system that ignores signalling.

I'm pleased about that! It's my personal opinion, which I sometimes feel the urge to mention when beginners start raving to beginners that it is the best thing since slot cars. :-)

I'm telling you that like all electronic equipment, it is great if you want to achieve results that are within it's limitations, but if you want to move beyond it's limitations then you're stuffed.

Come back to earth! Yes, I drive individual trains and it's great to be able to drive individual trains without the hastles of cabs, blocks and signals.

Once one starts to build a prototypical layout the signals and their operation become an important part of the system. Perhaps you are never going to go that far with model railways and that's your perogative. If you can't see a signal from your driving position then how are you going to correctly drive your train?

Once you start dividing up your layout into signal blocks, you've divided your layout into electrical blocks. You need detection for each block so you need to put in feeds and detectors. An on/off switch in the feed is much simpler and cheaper than a decoder in a loco.

I've rejected DCC for the reason that the advantages do not outweigh the disadvantages as well as the cost factor. Had it not been for the cost factor I would long ago have converted fully to DCC but I would now be faced with working around those disadvantages by adding yet another layer of expensive technology.

Regards, Greg.P.

Reply to
Gregory Procter

I'm running a 1982 IBM PC which I've upgraded to 384 kb of memory (from 64kb) and a floppy! OK, so I've got an old 486 with a VGA monitor as backup. Figure the value yourself ;-)

The program cost was purely time, and a couple of floppies.

That's simple enough to fix: I don't use the time honoured dead section in front of the signal (ker-runch) because I use double heading and sometimes bankers. The detectors cause the effective track voltage to drop and then the signal track section detector brings the effective track voltage to zero. I leave the center section live because my coach lighting system uses the very short 15v PWM pulses to keep the lights on. A simple change of programming can turn off the center section as well. I learned the lesson from a modern image SBB modeller who runs push/pulls etc.

I'm only modelling my prototype, and I have to work around the problem of analogue powered coach lighting. :-)

Regards, Greg.P.

Reply to
Gregory Procter

Hey, how did you guess? ;-) I don't have friends on call anytime I feel like operating.

Sure, I quite agree with you at the basic level. Your form of operation would be quite suited to a New Zealand layout, but even though I live in NZ.

I'm more taken with European operation. The section of line I've chosen to model was from it's earliest years always a bottleneck, with improvements and technology constantly being added to increase it's capacity. Each train runs from signal to signal, with a train ahead and one behind and the signals maintaining safety. If I had sufficient friends to drive each train individually then there wouldn't be enough room in front of the layout for them all to stand! If this was modern image rather than 1930 the trains would be moving too fast for the operators to stay with their trains.

Now you've identified the moment when I blundered in! I commented on/disagreed with a recommendation to a beginner that he should go for DCC from the beginning.

Regards, Greg.P.

Reply to
Gregory Procter

LOL. However, you missed my point (Pun intended). On the prototype, the points (Call them what you will) don't have to be set for the track you're on for you to drive backwards and forwards.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

OK, I stand corrected.

Actually, I wish I did and I wish I had the knowledge to program it to run trains realisticly. However, I'd only want the computer to run trains automatically to and from hidden staging. That way, my operators would never have to know of the staging yard's exsistsnce, so to speak. The computer could run the train from staging into the arrival track and hand over control to the human operator. It would also pick up train from the same track(s) and drive them, realistically, into staging.

The computer could include programming to simulate late running trains, delayed elsewhere on the system. In North America, timetabled trains rarely ran/run ahead of schedule, the rules don't permit it. Of course, these days, the only timetabled trains are passenger trains and these days they're inferior to freight trains.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

"Gregory Procter"

Yes. I'd pay for an "Automatic Crispan". to take charge of my staging arrivals and departures.

I take back what I wrote about you not knowing about "operation" and DCC. I stand corrected. We just see it from a differing perspective.

On my GER, if there's no other human operators available, I run the trains in the timetable one at a time in sequence. As I use a car forwarding system involving individually number freight cars and waybills to assign destinations, it's important to keep the car cars and waybill (As they are known) from getting too mixed up between operating sessions.

I mentioned that I only added DCC , at first, to some 20 locos, out of a stud of around 50. That was for the very first full operating session with all the guys present. Since then, once or twice per month, limited budget permitting, I've add decoders to all the locos and am now able to ring the changes as required. However, having more than about 23 locos on the layout at one time starts to overcrowd the small three stall roundhouse at Granville Junction. 10 locos and the roundhouse tracks are jammed to capacity. The two road engine-house at Berger yard can only take six locos at most and then all the engine yard trackage is also jammed tight.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

"Gregory Procter"

No, the points do not have to be set for a loco to run backwards and forwards on the track. All (Non staging) tracks are live all(most) all the time.

I handlay all my trackage. I don't use commercial trackage except in staging yards.

Yes, except for roundhouse, engine house, and staging tracks. For safety.

Every single loco and item of rolling stock on the GER has a "Car Card"

This is a small file car with a pocket on it for a waybill. The car card carries the AAR code of the rolling stock, XM = Boxcar, FM = Flat car etc. and the reporting marks, the alpha-numeric number of the piece of equipment. e.g. CN 123456.

My locos also have a car-card. In the waybill pocket of the train the loco is assigned to. e.g. Train 321, Local Passenger, Montreal (Windsor Station) to Atwater, at the end of my modelled part of the GER. The car card shows the Engine Number, wheel arrangement, class and any restrictions on its movement. For instance, every loco in each of my two classes of 4-8-2s carries the restriction "Not permitted East of Granville Junction, account curvature and light bridges."

Every train then is made up of car cards and waybills. These travel together, with the train, in a convenient package. In the staging yard, there are hooks for each track and the loco car card can be clearly seen as it's always the top car card.. Hence, loco number 528 has address number

28, so there's no confusion. At present, I use the last two digits of a loco as the address, so no two locos on my railway have the same last two numbers. Not prototypical perhaps, but for now it works.

LOL. That's why I do have on/off switches on my staging tracks and the roundhouse and engine house tracks. However, remember that I operate a North American layout. At Granville Junction, I have a small three road roundhouse. Each track in the roundhouse only takes one loco and my locos have numbers both on a brass plate on the smokebox door, which is usually first in the roundhouse, and painted in scale 12 inch high numbers on the back of the tender. So, by glancing into the roundhouse door, I can easily read the number of a loco on a roundhouse track as the large tender numbers are easily visible.

At Berger Yard, in Atwater, I also have a two road engine house. However, once again, each engine house track only accommodates one loco. At the engine house, the locos are usually backed in, to keep the stack (chimney) closest to the door, so I can read the number on the smokebox door.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

It's no more difficult than learning a foreign language - well, it is actually a simple, structured foreign language in mock english. ;-)

That's where I started!

You're getting the idea! :-)

In addition I was faced with building a new control panel for my layout. I hate building control panels because I keep changing details on the layout faster than I build control panels. At some moment in time the the thought occured to me - 'why not build the panel as software in the computer?' That way any changes are only in software and in minimal wiring and pointmotors on the layout.

I did a trial run on my little shunting layout and now am putting the lessons into practice on the main layout.

There's all sorts that can be added to the computer; timetabling and wagon forwarding will (eventually) come next.

Regards, Greg.P.

Reply to
Gregory Procter

OK - stage one is add DCC accessory decoders to your pointwork. stage two is a computer interface and a computer. (Maerklin Interface 6051 second-hand will do the job, Arnold 86051 will be even cheaper because it has Arnold instead of Maerklin written on it) stage three is play with the Basic program (on disk) that comes with it. stage four - ask someone what comes next. (me for instance)

You're forgiven ;-) Actually I speak "operation" in a number of languages; New Zealand, English, Australian, American and German.

Wait 'til I get my car forwarding program running - it's near the top of my 1994 five year plan!

I'm sorry to hear that :-( Sounds like our layouts have about the same capacity - because of the variety of locos over my prototype I need :-) twice as many locos as will fit on the layout.

Greg.P. Takaka, NZ.

Reply to
Gregory Procter

I use Micro engineering code 70 with the sleepers respaced to (my) prototype and some hand laid turnouts. I decided life was too short and am adding Peco code 75 turnouts modified to fit. One of everything code 100 in the staging area.

Your cats pee on the tracks?

Been there, done that :-) I'm working on having the computer take over the task.

Perhaps I should paint big numbers on my locos - or just move up to 1 scale.

Yeah, being able to read might be a help!

Regards, Greg.P.

Reply to
Gregory Procter

Gregory Proctor:

Then it's disingenuous to claim that you're operating a prototypical block-based system.

Reply to
Chris Fieldhouse

Digital Crispin, which I fondly remember running on my ZX Spectrum.

Reply to
Chris Fieldhouse

No more disingenuous than for me to claim I'm modelling a specific prototype at a specific period in time. I'm probably not the only person here doing that!

Regards, Greg.P.

Reply to
Gregory Procter

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