Agenda

My history with DCC Considering DCC? Experiences with systems I've owned JMRI and DecoderPro Tips and tricks The future

My history with DCC

Been using DCC since 1993

Will be sharing my good experiences

Also sharing the not-so-good experiences

And even sharing a few horror stories

Disclaimer

Will be sharing pros and cons of DCC products Bashing not my intention, just honest experiences Much of this clinic is subjective opinion, and you

may disagree This is what has worked for me on my Siskiyou Line

Considering DCC?

What the heck is DCC?

Why go DCC?

Isn't DC simpler?

Do I need DCC on a small layout?

I have too many locos to convert

What's the best DCC system?

What the heck is DCC?

DCC is to model trains what radio control is to model cars and model airplanes

You can independently control each loco

Prior to DCC, independent control meant complex wiring solutions with toggles or relays

Can do more than just control locos

While DC does give a measure of independent control, accidents can happen

Why go DCC?

DCC gives independent loco control with only two track power bus feeds everywhere

DCC sound gives the most options for loco sound

Less obvious advantage: independent loco performance tuning

In this photo, Mark Brown is running a train on the Siskiyou Line using a massive 5-unit DCC consist, with each loco individually tuned so all the locos pull consistently and run well together.

Independent loco tuning

Start, mid, and top voltage

Kick start

Reverse trim

Start up and stopping momentum

Fancier: torque compensation, back EMF

Conclusion: your loco fleet can perform better and run more consistently on DCC than on straight DC

Isn't DC simpler? No question that on a tight budget

and running just one train at a time that DC is simpler and cheaper

But if you want to run more than one train at a time, DCC is hard to beat – especially wireless DCC!

“I decided to save a few bucks and go DC [on my previous layout]. Therefore my layout had over 100 toggle switches and saying it was a complete mess to run would be an understatement. It used to take 30 minutes to train new operators to even get a train running, and my operators were all nuclear engineers – no kidding.

I am going to make the transition to DCC on my new layout. This is a no-brainer for many people, but it's not worth the up front savings of money for all the headaches of DC when it comes to installation, troubleshooting, and ease of operation.” - Peter Brahan, Layout Design Lessons Learned, LDJ-37

Do I need DCC on a small layout?

The great DCC loco tuning features may be worth it For more than one train at a time, hard to beat DCC To compare honestly, use high-end DC power packs

with momentum, plus block wiring and toggles• $100 per train (approx.) on straight DC• Good DCC starter system is $150

Two trains DC: $200 DCC starter system plus extra throttle: $250

Do I need DCC on a small layout?

Fleet decoders can now be had for $12 each

On DC layouts, even advanced ones, you still have to be careful to avoid loss of control accidents

It's hard to imagine operating Jim Providenza's 1970's era Santa Cruz Northernwithout using DCC. If you had to also keep track of cab control blocks along with all the other considerations needed with TT&TO, the complexity would be overwhelming. Under DCC, Jim just hands you a throttle, and says “go dial up your loco number, read your timetable, and good luck!” No other layout orientation is really needed or necessary, thanks to DCC.

I have too many locos to convert

True enough, even $12 x 70 locos (for example) is a lot of money

But how many locos do you run at once?

Pick the dozen locos you run the most often and convert them ($144)

For about the cost of another nice plastic diesel, you will have converted 1/6th of your fleet already

Is it worth the cost of one new brass loco ($800) to upgrade the loco performance of your entire fleet?

What's the best DCC system?

Most common online forum question ...

But that's like walking into a meeting room and asking: what's the best car to buy?

Like the best car question, the answer really depends on your needs and personal preferences

Most of us are familiar with auto purchase trade-offs, but not so with DCC

Most DCC product comparison matrices don't cover the DCC system practical considerations very well

DCC system practical considerations: What's available locally? If other local modelers use the

system, lots of on-site help is available if you have an issue

Digitrax has the largest market penetration

NCE is second in market penetration

Check what other modelers near you are using if you don't know!

Find out if your LHS carries it

DCC system practical considerations: How easy is it to use? You don't see this one on anyone's feature matrix

It can be quite subjective

Thirty years in software development means I have definite opinions on this topic

Here's how I define ease of use: can you guess how to do something just by looking at the command unit? (You can't use the manual ...)

I delve into this question in more detail elsewhere ...

DCC system practical considerations: How reliable is the system? Another item you don't see on anyone's feature

matrix

This is the heart of the “best system” question

Best way to get an answer is to ask people who own the system and use it regularly (2 yrs+ ideal)

One good place to get this info is online. More about that in a moment.

Does the system have quirks?

DCC system practical considerations: How reliable is the system? Online DCC support forums:

– Digitrax: http://groups.yahoo.com/group/Digitrax– NCE: http://groups.yahoo.com/group/NCE-DCC– Lenz: http://groups.yahoo.com/group/DigitalPlusbyLenz– EasyDCC: http://groups.yahoo.com/group/easydcc– MRC-DCC: http://groups.yahoo.com/group/MRC-DCC– Bachmann: http://groups.yahoo.com/group/Bachmann_DCC– Zimo: http://groups.yahoo.com/group/Zimo-DCC

DCC system practical considerations: How reliable is the system? Size of the DCC support forums:

– Digitrax: 8119– NCE: 3627– Lenz: 2221– MRC-DCC: 1249– EasyDCC: 623– Zimo: 423– Bachmann: 257– Atlas: [none]

Not necessarily an indicator of the best system ... I could take the cynical view ...

My experiences with Lenz, EasyDCC, and NCE

Started with Lenz in 1993 Moved to wireless EasyDCC in 2000 Then moved to NCE wireless in fall of

2007 Each time I considered a move – any

DCC system was an option Would download manuals and revisit

each system's features Would price out each system with 10

wireless throttles in operation at once

My experiences with Lenz, EasyDCC, and NCE

NCE's biggest advantage has always been its user interface

Digitrax's user interface started very inconsistent but has improved

EasyDCC and NCE come with the computer interface built in

NCE downside has been entry cost I was recommending a Digitrax Zephyr as

a cheap starter system NCE PowerCab now competes with Zephyr

Tethered versus wireless

I started with a Lenz DCC system in 1993

For tethered, lots of plugsclose together is better

Put one plug every 5 feet MY dream was to ditch the

tethers completely Moved to EasyDCC

wireless in 2000 Use only wireless throttles

Tethered versus wireless

To see what wireless buys you, see the above photo from a recent op session on my HO Siskiyou Line

Not every moment of an op session looks like this, but when things get busy, not having tethers really helps

So what's the big deal with tethered operation?

If you are into prototype operation, model railroading thoughts matter:

plug in assign throttle to loco crack throttle to see if loco works – yep check lights (and horn/bell, if sound) take slack out, make sure everything is

coupled, put slack back in ("brake test") once have clearance to go, slowly rev up

throttle and walk along with train unplug look for next socket find next socket and plug in look up to find train – oh there it is watch train, adjust throttle as necessary

whoops, train is getting past where I'm plugged ... better start looking unplug look for next socket find next socket and plug in look up to find train – oh, there it is watch train, adjust throttle as necessary whoops, train is getting past where I'm

plugged ... better start looking ... and so on

Tasks in RED are model railroading thoughts with tethered walkaround throttles

So what's the big deal with tethered operation?

If the red tasks don't bother you, then most likely you:– Haven't done serious operation with wireless

throttles– Or you are mostly a “railfan” and not an “engineer”

Once you get into serious prototype-based operation, full wireless DCC operation is a dream-come-true

The current Digitrax wireless offering still needs the first red step: plug in to acquire the loco.

Moving from another wireless system to Digitrax means running a bus around the layout again (no thanks)

Moving from EasyDCC to NCE

I've now moved to wireless NCE to get wireless POM and go beyond EasyDCC's 8 frequency limit

My current EasyDCC system (8 yrs old) was completely obsolete and having a few issues

Complete replacement of my DCC system with NCE was cheaper than a major upgrade of my obsolete EasyDCC system

Started with NCE PowerCab ($140) to program locos at the workbench

Purchased CS02 command station ($160), so for $300 could power my layout with an NCE system

Moving from EasyDCC to NCE

Next, got an RB02 receiver ($125) and a single wireless Cab04PR throttle ($160) and I now had wireless capability

It all dropped right in place with my current boosters and “just worked” with minimal effort

I then sold my EasyDCC system and throttles and used the proceeds to buy 7 more NCE wireless throttles

EasyDCC system gave me great service, but my 900 series throttles have become obsolete with the latest firmware upgrade

I have not been happy with EasyDCCs direction of late

Moving from EasyDCC to NCE

EasyDCC wireless gave excellent service from 2000 – 2007 Here you see Terry

Roberts as Roseburg Yard master using a wireless throttle. In the background is

the EasyDCC command station, with two additional throttles, which were seldom used during a session.

As time went on, I wanted a system with more throttles on dedicated frequencies, and EasyDCC kept limiting their consisting features, while NCE kept expanding theirs. EasyDCC stopped selling my current throttle model, and my old throttles began

malfunctioning on occasion. EasyDCC's new premium throttle was very pricey $220+)So in late 2007, I sold my EasyDCC system and moved to NCE.

Moving from EasyDCC to NCE

Here's where my EasyDCC command station used to be, now with the one-and-only plug in location for my NCE system. I've pressed the NCE

PowerCab into service as a system monitor, and keep it plugged in here so I can check the system if needed during an op session.

Ordinarily all operation is conducted with wireless throttles, mostly simple Cab04pr's that have a nice large speed knob and clearly labeled keys like “Select Loco” or “Horn” for common operator functions. NCE wireless was more finicky than EasyDCC wireless until NCE released its rev 3

wireless in February of 2008. Now NCE and EasyDCC's dedicated frequency wireless performance are both rock-solid reliable and give rapid reponse.

Moving from EasyDCC to NCE

Here we see Jeff Shultz using an NCE Cab04PR wireless throttle NCE's smart double-

ended decoder-based consists takes consisting to a whole new levelCommand station

consists are no longer needed (a good thing)

NCE's POM momentum button is also pretty cool ...NCE's throttles all have simple, plain English buttons for common things like selecting a

loco or blowing the horn. How about a button labeled “select loco” to dial up a loco? Or a button labeled “horn” to blow the horn?No more “secret code” keys or labels to memorize, operators just must be able to read!

DecoderPro

Free, open source software that is part of the JMRI (Java Model Railroad Interface) initiativeJava-based app for

programming decoders that runs on Windows, Mac, and LinuxConstantly growing and

improvingDid I say it's free?

Determine decoder type without removing the shell!Use IDENT function (comprehensive programmer) - reads CV7, 8 for you and looks it upNewest decoders may not be in DecoderPro, join the JMRI Yahoo group, download the

extra decoder filesLink: http://groups.yahoo.com/group/jmriusers/ Install new decoder files: http://www.decoderpro.com/apps/DecoderPro/FileUpdate.html

BlueLine decoder woes

BLI attempted to economize by just providing a sound decoder (to program use Direct Mode, not Paging Mode)

You have to still buy and install a motor decoder Now have a problematic dual decoder arrangement NMRA dual decoder scheme uses CV15 and 16 Better dual-decoder option: short/long address trick

BlueLine decoder woes

Using CV15/CV16 locking ...– Start with one decoder in the loco (sound decoder)– Set unlock code in CV16 (2 is a common value)– Set CV15 to same number to unlock (2)– Once done programming CV's, set CV15 to zero (lock)– Install motor decoder– Set unlock code in CV16 (1 is common value)– Set CV15 to same number to unlock (1)– Once done programming CV's, set CV15 to zero (lock)– When locked, can only set CV1 (short adr) & CV15

(unlock)

BlueLine decoder woes Short address / long address trick ...

We'll use 4411 as the loco number– On the programming track set long address to 4411 and short

address to something like 44– Set CV29 to 06 to make decoder use short address (44)– Install motor decoder in different loco, then on programming

track set long address to 4411 and short address to 11.– Set CV29 to 06 to make decoder use short address (11)– Install motor decoder in BLI loco & put on main (program on

main - POM)– POM loco 11 (motor) with desired settings, POM loco 44

(sound) with desired settings– When done, POM loco 11 CV29 to 34, POM loco 44 to 34– Both decoders will respond to 4411 as expected in all cases

BlueLine decoder woes Short address / long address trick ...

– WARNING:– Avoid programming any CV's other than CV29 or CV19 when

BlueLine is set to long address– Always set CV29 to 6 before programming any other CV's or

you may get unexpected behavior problems– After setting CV29 to 6, you program the motor decoder at

address 11 and the sound decoder at address 44– Once you are all done, put 34 into CV29 of address 11 and

address 44, which again combines them into one loco: 4411 Using this method keeps CV19 unlocked and allows decoder-

based consisting to work as expected

Remember to use Direct Mode programming (doesn't work with EasyDCC computer interface when I last checked ...)

Short Management

Short management (or lack of it) is DCC's dirty little secret

Basic DCC short management is poor at best –“OK, WHO SHORTED THE LAYOUT?”

In the old cab control days, track was gapped into train length blocks and each train had its own power pack –when a train shorted things, it only affected that train

Under DCC we no longer gap the track into blocks and all trains can share one power pack (called a booster)

The result? A short anywhere shuts down the layout!

Short Management

Short Isolation: more boosters Cut the layout up into power districts, which isolates

shorts now to just that district Power districts generally much larger than train length

– 4-5 amp boosters are not cheap– 4-5 amps is enough to run many trains

Most common place for shorts is at turnouts, so isolate many turnout locations (like yards) into their own power district

Other rule-of-thumb is to break up long mainline power districts into two power districts

Short Management

Short Management: train length blocks Shorts on a DCC layout does bad things

– Scrambles decoder settings– Damages wheels or track– High inrush current sound decoder prevents booster reset

With train length blocks & short management, the booster “absorbs” the short and everything else keeps running

Only the train that caused the short stops running The key is to install a current limiter to each train block

– Can use Tony's Power Shields ($30+ each)– Or can use the lowly automobile tail light ($1 each)

Short Management

The humble 1156 auto tail light bulb

First suggested in the 1960s to prevent short damage to delicate transistor throttle circuits

For $1-$2 per train block, the 1156 bulb will limit the current from a short to about 2 amps, rather than allow the full 5-10 amps of your booster flow through the short.

This makes shorts with a DCC system act more like the good old days of cab control, where the typical power pack was at most about 2 amps.

Short Management

Wire the bulb in series with one of your track feeders ...

Ordinarily when cold, the bulb acts as a very low value resistor, having almost no effect on the DCC current available to the track.

But if something shorts the track, the bulb will suddenly glow bright, becoming the load in the circuit and limiting current flow to around 2 amps.

Short Management

Let’s watch it demonstrated!

Short Management example movie

Short Management

Wiring in the bulbs for one booster district ...

Short Management

Marcus Ammann (well known modeler from Australia) comments:

... while building a demonstration DCC module I came across this problem: with more than one Soundtraxx equipped loco in the same power district my NCE EB3 circuit breaker would not reset.

I looked up Tony's site and under his auto reversers ... it said that the reverser had problems resetting with Soundtraxx locos in the same power district.

Mark Gurries on the NCE group suggested I wire a 12 volt lamp in parallel with my NCE EB3. I tested with different wattage lamps and was able to get the results I wanted with 5 - 10 watt lamps.

Short Management

Marcus Ammann (well known modeler from Australia) comments (continued):

… Tony's Power Shields, Digitrax's PM42s and PM4s as well as the NCE EB3 were having the problems, along with some power boosters.

About August/September last year, many modelers on the QSI group voiced their frustration about this problem. All DCC system seem to suffer the same problem.

At Joe’ Fugate's great layout web site he also has a reference to light globes for short protection and now has a 3 minute video clip where Joe explains about light globes …

Short Management

Marcus Ammann (well known modeler from Australia) comments (continued):

… The booster not being able to reset after a short circuit with a few sound locos in the same zone does not happen when using light globes as Joe suggests, because the booster never shuts down if everything is working correctly EXCEPT when you are operating near the booster’s current limit. When that happens, it's time to add a second or third booster.

Thanks a lot Joe.

Short Management

Marcus has done his homework, he says:

An 1156 bulb (27 watts) limits current to 2.1 amps, while a two-filament 1157 bulb (33 watts - if the filaments are wired in parallel) increases the current limit to 2.5 amps. Wiring two 1156 bulbs in parallel increases the current limit to a whopping 4.2 amps.

This means using something like:– Two 1142 bulbs in parallel (18 watts) would give you a 3 amp current limit

– Two 1152 bulbs in parallel (17 watts) would give you a 2.8 amp current limit

With today's higher amperage sound locos, a 3 amp limit seems about right

The 3 amps would not limit multi-loco consists much, yet keep the current low enough to not get bad damage from a short. Using two 1156 bulbs in parallel lets over 4 amps flow in the short, and it may cause the booster short protection to trip.

Short Management

Marcus has done his homework, he says:

An 1156 bulb (27 watts) limits current to 2.1 amps, while a two-filament 1157 bulb (33 watts - if the filaments are wired in parallel) increases the current limit to 2.5 amps. Wiring two 1156 bulbs in parallel increases the current limit to a whopping 4.2 amps.

This means using something like:– Two 1142 bulbs in parallel (18 watts) would give you a 3 amp current limit

– Two 1152 bulbs in parallel (17 watts) would give you a 2.8 amp current limit

With today's higher amperage sound locos, a 3 amp limit seems about right

The 3 amps would not limit multi-loco consists much, yet keep the current low enough to not get bad damage from a short. Using two 1156 bulbs in parallel lets over 4 amps flow in the short, and it may cause the booster short protection to trip.

Short Management

So working our way up the list we have:– 1. One 1152 bulb - 1.4 amp limit– 2. One 1142 bulb - 1.5 amp limit

– 3. One 1156 bulb - 2.1 amp limit– 4. One 1157 bulb - 2.5 amp limit (if both filaments wired in parallel)

– 5. Two 1152 bulbs - 2.8 amp limit– 6. Two 1142 bulbs - 3.0 amp limit *– 7. Two 1156 bulbs - 4.2 amp limit

– 8. Two 1157 bulbs - 5.0 amp limit (if both filaments wired in parallel)

* Sweet spot

Short Management

The other consideration is how many amps a short will draw from the other trains in that booster district.

– Example:

– 5 amp booster district– Train blocks with 1156 bulbs

– A short will consume 2.1 amps of the 5 amps– Other trains in the booster district have 2.9 amps

● The higher you raise the short limit, the less booster capacity you leave for other trains when a short occurs.

● You may need to experiment with certain bulb combinations and the size of your booster districts to get a good balance

– bigger district – more trains may be in the district = need more leftover amps– smaller district – fewer trains may be in the district = need less leftover amps

Short Management

One final note: avoid the temptation to go with 8 or 10 amp boosters unless you use something like the bulbs to limit the current

With a 10 amp booster and 14 volts output, you will be running the equivalent of a 140 watt resistance soldering iron through the short contact point. Meltdown time!

If you use the bulbs as explained, you limit the current to the track as described, allowing you to use 8 or 10 amp boosters on an HO layout! The bulbs will limit the short current, saving your equipment!

Not bad for about $2 per train block– if you burn up that new BLI sound loco with an unprotected 10 amp short,

you'll easily be out more than it would cost to short protect a large club layout with the bulbs.

DCC Friendly turnouts

DCC friendly simply means:The turnout has less chance of a short if something doesn't track right through it.

If you ever operate on a DCC layout with turnouts that keep getting shorts, you'll quickly understand the origin of the term “DCC friendly turnout”.

There is a lot of confusion over:

What is a DCC Friendly turnout?

Do I use “live frog” or “dead frog” turnouts?

DCC Friendly turnouts

Dead frog turnouts (also called 'insulfrog') are more DCC friendly than live frog turnouts (also called 'electrofrog')

If you enter a live frog turnout from the frog end with the points thrown against you, you'll get a short.

Shorts are bad (and could get ugly) on a DCC layout unless you have taken steps to create robust short management.

– The cry of “who shorted the layout?” is common on a DCC layout with live frog turnouts and no robust DCC short management.

● Dead frog turnouts are less work to install and maintain since there's no frog power routing contacts or wiring to bother with.

● On a DCC friendly turnout, the points are also the same polarity as the stock rails.

– If something doesn't track right around the points, you are much less likely to get a short.

DCC Friendly turnouts

I started out using live frog turnouts on my 1980s SP Siskiyou Line layout (HO)

Moved to dead frog – Easier to install

– My all-wheel-pickup diesels generally run fine over dead frogs

Gary Segal (huge L&N layout featured in MR back in 1996) and asked him which he used – live frog or dead frog

– He started out using live frog but moved to dead frog because things run fine on them, they're simpler, and they cause less short headaches with DCC. So I'm not the only one!

If you have older steam locos or extra short wheelbase locos, you may have to stick with live frog turnouts.

But if you can use dead frog turnouts, they remove one more source of troublesome shorts on a DCC layout.

DCC Friendly turnouts

Live frog (Electrofrog)

Advantages:– No dead spots in the track

– When entering a turnout thrown against you from the frog end, the train stops (shorts) preventing a derailment.

Disadvantages:– Need contacts to route power reliably to the frog, which is more work since

using the points alone is not reliable over time.– A short on a DCC layout during “normal operations” is generally BAD.

DCC Friendly turnouts

Dead frog (Insulfrog)

Advantages:– Easy to do – no extra wiring

– No short if the turnout is thrown against you – you just go on the ground like the prototype ( which can about 10% of the time cause a short ... so nothing's perfect).

Disadvantages:– Dead spots in the track can be bad– May have to cut gaps around the frog – which means more work.

DCC Friendly turnouts

You can get dead frog DCC friendly turnouts from several sources today:

– Atlas code 83 Super -Switch (#4, #6, or #8)

– Peco insulfrogs– MicroEngineering turnouts

– Walthers/Shinohara DCC Friendly models (although in high demand so are often out of stock)

– Fast Tracks jig-built turnouts are DCC friendly, as are turnouts made using Central Valley tie kits according to the methods I describe on my web site.

Older Shinohara/Walthers turnouts need modification to be made DCC friendly …

DCC Friendly turnouts Modifications needed for an older Shinohara

turnout to make it DCC friendly

DCC Friendly turnouts Peco insulfrog problem – and the fix

Simple fix:

Grind down the spot inside the red dotted line shown

Then super glue some black styrene in the grove and trim it

You'll never have a short problem again!

Why you WANT a computerinterface

Most modelers think a computer interface is to have the computer run trains – boring !

Wrong!

A computer interface is the single most important feature of a robust DCC system.

The reason is because a computer interface allows you to rapidly and easily program complex decoder settings – all with just pointing and clicking with your mouse!

Decoder programming doesn't get much easier with a computer interface!

With free DecoderPro software, a PC, and a computer interface, you can point and click your way to decoder programming nirvana!

Why you WANT a computerinterface

As decoders get more features, and as sound decoders become more robust, the number of configuration variables (CVs) you need to program have been skyrocketing.

Here’s a rundown on what systems have:– NCE ProCab system comes with the computer interface built in– EasyDCC comes with a computer interface built in (EasyDCC requires you

build a special cable, however– Full Zimo system also comes with a computer interface

– All other DCC systems require you purchase the computer interface separately, at a cost of $40-100

– The new MRC Prodigy Advance Squared system lists a computer interface for $200, which seems very pricey!

My favorite decoders ...

Barebones fleet decoder ($13): D13SRJ from NCE.

Available for $11 in quantity

Torque compensation feature is simply outstanding.– Can deliver pulse spikes at startup and yield some very nice slow-speed loco

performance. – As the loco speed increases the extra pulse spikes die away into normal pulse

modulated DCC power to the motor, so it runs smooth, cool, and quiet.

Greatest weakness of the D13SRJ is its lighting functions – They're not very convincing or configurable.

Very easy to add a “keep” alive circuit to the D13SRJ – Keeps the loco moving on dirty track and across dead frogs without ever

stalling.

More coming ... Check out:

Model Railroad Hobbyist magazine:http://model-railroad-hobbyist.com

Plan to include many rich media ezine articles on DCC (can include video clips)

The magazine is totally advertiser supported, so downloading is completely free (just subscribe, which is also free)

First issue, January 2009

More about the new ezine in mySiskiyou Line Potpourri clinic