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Overusing DCC decoders

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Overusing DCC decoders
Posted by ndbprr on Wednesday, May 11, 2016 11:41 AM
What is the advantage of using a decoder equipped device like a turnout or car lighting.? My logic say's keep the DCC to the engines and separate turnout control to a dispatch panel like the real railroads. Is there really an advantage to controlling passenger car lights with a decoder? A cheap diode bridge could do the same thing for far less money since lights are either on or off. And really passenger car sounds? Never yet heard any internal sounds when one passed. We are reaching overkill.
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Posted by maxman on Wednesday, May 11, 2016 12:05 PM

ndbprr
What is the advantage of using a decoder equipped device like a turnout

If someone decides someday that he would like to have a dispatcher controlling a route remotely, then there needs to be a method of interfacing the control device, like a computer, with the DCC system.  Typically a decoder makes this easier.

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Posted by rrinker on Wednesday, May 11, 2016 12:13 PM

 Well, it would be nice to turn off the lights. I suppose if you had a coach yard you could use some switches to kill power to the tracks like in an engine area so all the sounds don't fire up. If there are blinking markers and so forth, it's probably 'easier' to use a function only decoder than wire up a blinker circuit and suitable power supply.

 I agree on turnouts - although I DO hook them all up to DCC, but only as a means of communicationg with the dispatcher panel. None of the common DCC systems makes it particualrly easy to switch between train running and turnout operating. And since the computer is already hooked to the DCC system, why install a second adapter and second control bus when there's one right there, by the tracks where the turnout will be?

             --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by gregc on Wednesday, May 11, 2016 12:48 PM

ndbprr
My logic say's keep the DCC to the engines and separate turnout control to a dispatch panel like the real railroads.

the NMRA is working on Layout Command Control (find under their Recommended Practices page) for controlling devices not on the track (i.e. turnouts, signals, ...).  It appears designed by committee and targeted for high end users.  

Other model railroads have developed their own control bus, similar to Bruce Chubb's C/MRI that use approaches similar to NCEs RS-485 based cab-bus.

do lighted cars on DCC need anything more that an LED and resistor?

greg - Philadelphia & Reading / Reading

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Posted by mlehman on Wednesday, May 11, 2016 12:54 PM

gregc
do lighted cars on DCC need anything more that an LED and resistor?

Not here. I have a couple of hundred LEDs installed as car lighting. I use a resistor, cap, and bridge recitifier in most cases, as I tend to use the strip light LEDs that can be cut into 3-unit segments for passenger car lighting. All are constantly on. The light levels are significantly dialed down. IMO, you should either not see or barely see that lights are on in the daylight, so you don't even notice they're on when the sun is up. At "night," this is  sufficient for very realistic light levels in the cars and is more than sufficiently visible.

I do use DCC accessory decoders on my standard and a few dual gauge turnouts in locations that would typically be controlled by a dispatcher remotely. Usually there is NOT a dispatcher on duty, so it's mostly as a matter of convenience

Mike Lehman

Urbana, IL

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Posted by Bayfield Transfer Railway on Wednesday, May 11, 2016 1:37 PM

ndbprr
What is the advantage of using a decoder equipped device like a turnout or car lighting.? My logic say's keep the DCC to the engines and separate turnout control to a dispatch panel like the real railroads. Is there really an advantage to controlling passenger car lights with a decoder? A cheap diode bridge could do the same thing for far less money since lights are either on or off. And really passenger car sounds? Never yet heard any internal sounds when one passed. We are reaching overkill.
 

 

The advantage is that the manufacturers get to sell more stuff.

The fact is some people just like gadgets, so the DCC manufacturers are making gadgets.  If they sell, then the manufacturers are right.

(Actually, for cabooses I am installing function-only decoders because these days it's an easy way to turn waycar markers on and off, especially if they're on the car end.  Also, the LM3909 is no longer made, so a decoder in the waycar lets me have a flashing marker where appropriate.  Since I'm using functions to control engine lights, consisting in the waycar and designating a function for the markers is no big deal.)

Disclaimer:  This post may contain humor, sarcasm, and/or flatulence.

Michael Mornard

Bringing the North Woods to South Dakota!

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Posted by santafe5000 on Wednesday, May 11, 2016 7:29 PM

But what about those times when you are on a Quantas flight from Chicago to Sydney and have a hankering to run trains.

You use your laptop connected via the planes wifi through your VPN to the computer controlling the PanelPro running the layout. You also have your layout under video surveillance so you can watch. And the decoder controlled turnouts allow you total route control.

James in TexasCowboy

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Posted by narrow gauge nuclear on Thursday, May 12, 2016 3:17 AM

As a lone wolf operator, I have all my  stall motor switches set to DCC control via the digitrax dual switch decoders.  While a train is creeping along I can punch "SW" on the Zephyr Extra, punch in the Switch number to change and hit "T" (turned) or "C" (closed) and get back to running the train.  You get used to it.  It is not much of a hassle as narrow gauge trains typically run at 15-25mph scale speeds.

I don't have a giant empire and it is a shelf layout, so I only have about 9 switches over the 28 foot long run.  As for the real narrow gauge, there was no real dispatcher or switch towers.  All engines typically stopped to throw a switch anyway as the brakemen left his doghouse on the tender as needed.

 

Richard

If I can't fix it, I can fix it so it can't be fixed

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Posted by gmpullman on Thursday, May 12, 2016 3:23 AM

Hi,

ndbprr
Is there really an advantage to controlling passenger car lights with a decoder?

Cool effect or gimmick? I guess it depends on how you want to portray your models:

If you want to skip through Matt's dialog jump to 3:10 and again to 4:25. Matt needs to trim some of the dead air from his videos Whistling

I have a few cars with function-only decoders for operating a Gyralight on the rear and turning on or off markers. For the investment of a $12. decoder it's worthwhile for me.

I also have a few Soundcar decoders. Some of the full dome cars had motor-generators and I like hearing—at very low levels—the sound of that eminating from my cars. The "big-hole" effect is neat, too!

In another case I have a C&NW cab car that is sometimes the "front" of the train so I use the decoder for the horn, bell and rotary beacon as well as air conditioner and turning on or off interior lights. The option is there, why not use it.

ndbprr
My logic say's keep the DCC to the engines and separate turnout control to a dispatch panel like the real railroads

Presently I do not have any logic controlled turnouts but I just might someday. I don't believe there's any conflict between running the engines and throwing turnouts. There's plenty of bandwidth on the network and there are more manufacturers getting into route control where I could see the advantages of having a full or semi-automated route control system especially if you were to tie it into a signal system.

Regards, Ed

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Posted by rrinker on Thursday, May 12, 2016 7:36 AM

 Accessory decooder and mobile decoder address spaces are completely different so there is no conflict. Turtnout #653 does not conflict with loco #653. Accessory decoders do not get continuous packet streams like a loco decoder, either, so the bandwidth utilization is very low. A loco decoder is periodically updated even if you haven't turned the throttle or pressed a button, but a stationary decoder only gets sent a packet if it is commanded to do something.

 What has been slow on the uptake, and thus has driven alternate bus arrangements, are devices like the Aux Box, which allow the control to take place over the DCC bus, but the power to come from some external source - driving all your structure lights with DCC power is quite silly and very expensive, when a simple (and they can be cheap - the Aux Box isn't exactly cheap) DCC controlled relay can switch lights on and off while powering them from cheap plain AC or DC power supplies.

                          --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by CSX Robert on Thursday, May 12, 2016 9:24 AM

ndbprr
...My logic say's keep the DCC to the engines and separate turnout control to a dispatch panel like the real railroads...

If you don't use a bus of some type, then you will have to run wires from every turnout back to the dispatch panel.  Personally, I'll be using Loconet for turnout control, but if I was not using a system with Loconet, then I would  use the DCC bus.

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Posted by gregc on Thursday, May 12, 2016 3:24 PM

CSX Robert
If you don't use a bus of some type, then you will have to run wires from every turnout back to the dispatch panel.

larger layouts would use input/output (I/O) cards that provide 8/16/... input/output lines to control devices in the vicinity of the card and connect the cards via an RS-485 bus back to a controller (i.e. PC).  Such a card can be used to control turnout position and signals, as well as sense turnout position and block occupancy.

This approach minimizes the amount of wiring instead of "leaching" both power and bandwidth off the DCC bus on the rails.

greg - Philadelphia & Reading / Reading

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Posted by SouthPenn on Thursday, May 12, 2016 11:14 PM

Most of my switches are manual. You have to walk around the layout if you want to do any switching. But I have a few that are controlled by my NCE DCC system. These switches would require reaching across and over the layout. My reversing sections are automated by PSX-ARs.

South Penn
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Posted by Renegade1c on Friday, May 13, 2016 12:33 AM
My previous layout and the one I'm currently building utilize loconet for communication but get power from an external power source. I have a 12 volt and 5 volt lines from an old computer power supply that supply power to all of the accessories (RRcirkits block detection, digitrax signalling, stationary decoders, structure lighting, etc.) This unloads the power requirements off the DCC system which the only handles train power,the psx circuit breakers and throttles and communication. An added benefit is that if someone runs a switch that is thrown against the and it shorts, the switch can still be thrown to clear the short because it's not powered by the "what would be shutdown" DCC bus. DCC power is to power trains not accessories IMHO. DCC power is expensive...quality 12 volt switching power supplies are cheap especially when you can easily run almost anything off of a 5 amp supply unless you have a warehouse size layout.

The one thing I really enjoy is that my dispatching panel only has two connections, a loconet cable and a power supply cable (12 volts), making it really simple to connect to the layout.

While I'm excited to see what comes off LCC, I think a lot of it is already available.


Colorado Front Range Railroad: 
http://www.coloradofrontrangerr.com/

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