Rapido Trains SW1200RS User manual

OPERATOR’S
MANUAL
FRANÇAIS AU VERSO

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SW1200RS LOCOMOTIVE PRODUCT GUIDELINES
Thank you for purchasing this model of the quintessential Canadian road switcher, the
SW1200RS. Since the infancy of Rapido, this has been one of the most requested locomotives
by our customers. We are certain you will not be disappointed.
If this is your first Rapido locomotive, we have to ask – where the heck have you been?
We’ve been producing models JUST FOR YOU for the last thirteen years and you’ve ONLY
NOW finally noticed our advances? Just for that, we’re going to make sure you LOVE your
SW1200RS. And then you’ll say to yourself, “What have I been missing all of these years? I
want to buy every Rapido model that has ever been released, ever, in every scale! Especially
that weird British one that tilts and looks a bit rude!” So we’re thanking you in advance for that.
If you are a returning customer, just put your engine on the track, don’t MU it with a Tyco F-unit,
and don’t burn it up with a cheap DC controller. Really – we’ll take MUing it with a Tyco F-unit
over using a cheap DC controller. Cheap DC controllers can turn Rapido models into Molotov
Locomotives.
We would like to warn you that this manual contains a considerable amount of inappropriate
linguistic innuendo, including four éclairs, two crevasses and an orangutan. But as these
naughty things only appear in that one sentence, you don’t have to worry about them any more.
As always, if there is anything amiss with your SW1200RS please do not hesitate to contact
us. We stand by our products 100%. The best way to contact us is through email (trains@
rapidotrains.com) but you can reach us by phone, Canada Post or Messenger Yak as well.
Please do not send a faulty model back to us without first getting authorization. If you bought this
model in 2018, stuck it under your layout, abandoned model railroading to start a Messenger
Yak farm, and have finally returned to the hobby at the ripe old age of 173, we’re most likely
dead. Use your Molecules “R” Us 4D Repromatic to replicate any part that doesn’t work. In
fact, just program it to build your entire layout. Due to planetary overcrowding, your layout is
restricted to the size of a box of Shreddies. So good luck with that.
CONTACT US!
Rapido Trains Inc.
500 Alden Road, Unit 21
Markham, Ontario
L3R 5H5 Canada
Tel. [phone] - Toll Free 1-855-LRC-6917
Fax. [phone]
Email. [email protected]

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TABLE OF CONTENTS
Prototype History..................................................................................................... 4
Break-In ................................................................................................................. 5
How to Hold your SW1200RS ................................................................................. 5
Checking and Adjusting Your Locomotive................................................................... 6
Missing or Damaged Parts ....................................................................................... 6
Removing the Shell.................................................................................................. 7
Operation – DC (Silent) ........................................................................................... 8
Installing a Silent DCC Decoder................................................................................ 8
Operation – DC (Sound) .......................................................................................... 9
Operation – DCC (Sound)...................................................................................... 10
• Locomotive Address ................................................................................. 11
• Turn On the Sound.................................................................................... 11
• Functions ................................................................................................ 12
• Functions: More Information ...................................................................... 12
• Horns ..................................................................................................... 15
• Sound Volume Settings ............................................................................. 15
• Sound Volume Settings Chart ..................................................................... 16
• Factory Reset ........................................................................................... 16
• Awesome Slow Speed Thingy .................................................................... 16
• More Information ..................................................................................... 17
Limited Lifetime Warranty ...................................................................................... 17
Acknowledgements .............................................................................................. 18
SW1200RS DCC FUNCTION QUICK REFERENCE
F0 HEADLIGHT
F1 BELL
F2 HORN
F3 CURVE SQUEAL
F4 FULL THROTTLE
F5 SLOW DOPPLER HORN
F6 DITCH LIGHTS (IF EQUIPPED)
F7 DIM THE HEADLIGHTS
F8 STARTUP/MUTE/SHUTDOWN
F9 CLASS LIGHTS
F10 TURN OFF NUMBER BOARDS
F11 CAB LIGHT
F12 SWITCHING MODE

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PROTOTYPE HISTORY
What exactly does the “RS” mean?
In short: Road Switcher. The SW1200RS is equally comfortable in the yard or on the
mainline.
As produced, the GMD (General Motors Diesel Division in London, Ontario) SW1200RS
differed from the standard SW1200 by having distinctive Flexicoil trucks (a GM design
offering improved suspension and ride quality versus the standard AAR-type switcher
truck); 62:15 gearing for a 65-mph top speed; multiple-unit capability; and large
headlight/numberboard fixtures on both ends. A 775-gallon fuel tank – vs. 500 gallons
on a comparable GMD yard switcher – helped the “RS” units venture beyond yard
limits. As with the standard SW1200, GM’s 12-cylinder 567C engine provided the
model’s 1200 hp.
Canadian National
CNR acquired a total of 192 SW1200RS units between 1955 and 1960, numbered
1204-1397 (there is no 1269 or 1270). Because they were internally pretty much
identical to the GMD-1, they received the same classification: GR-12. General Motors,
Road switcher, 1200 HP. There are two main spotting variations on the CN SW1200RS.
The earlier units, 1204-1290 (GR-12d/f/h/k/l) had a different style of number board
above the cab. As well, 1204-1318 and 1324 had EMD-style steps rather than the
usual Canadian straight steps. Contrary to modelling lore for those of us who pre-date
the internet, the 1200s and the 1300s have nearly identical hoods. The louvers are the
same.
Many CN SW1200RS locomotives were rebuilt into 7000-series locomotives in the
1980s, including 7100-7107. These are the famous “Sweeps,” a combination of
SW1200RS and GP9 uprated to 1350 HP. Man we would love to make those one day.
CN’s last SW1200RS was retired in 2014.
Canadian Pacific
Between April 12 and 20, 1957, CNR SW1200RS No. 1257 was loaned to Canadian
Pacific for evaluation out of Winnipeg, as CPR accelerated its dieselization timetable
and sought an effective “Branch Line Unit” (BLU) for service on low-density secondary
lines. This testing led to placement of CPR’s first order for this model, 31 units delivered
by GMD between June and October 1958 as Nos. 8100-8130 (class DRS-12a). They
arrived in CPR’s then-standard maroon-and-grey livery with Roman lettering, although
many units received script lettering prior to the introduction of the CP Rail Action Red
image in 1968.
CPR acquired two more groups of SW1200RS units: Nos. 8131-8146 (class DRS-12b)
in the spring of 1959, and Nos. 8147-8171 (DRS-12c) in mid-1960. Among the 1959
purchase were ten units (Nos. 8131-8140) earmarked for assignment to subsidiary
Dominion Atlantic Railway in Nova Scotia (but with standard CPR lettering), where they

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brought an end to DAR steam operation. In September 1960, SW1200RS No. 8171
had the distinction of being the final new diesel locomotive delivered as part of CPR’s
dieselization. It also proved to be the final example of the model to be built.
CPR’s locomotives shared the front number board/headlight assembly with the CN units,
but the rear of the cab had a more conventional arrangement and did not have integral
marker lights. Many CP units were extensively rebuilt in the 1980s and renumbered in
the 1200 series. The biggest spotting difference was the super ginormous sand filler
hatches on the hood. Others received ditch lights and other upgrades but remained in
their original numbers. CP’s last SW1200RS was retired in 2012.
What’s in a name?
Unofficially, the road-switcher variant of the SW1200 came to be known as the
SW1200RS. While at GMD’s London, Ont., plant conducting research for his book
Locomotives From London (UCRS, 1968), the late Peter Cox sought to clarify production
quantities for the SW1200, because out of the total number built by GMD only a few
were purely switchers; the majority were multi-purpose road switchers. Cox suggested
SW1200RS as a model designation for the Canadian road-switcher variant and GMD
staff concurred, although neither the builder nor CN revised their official records.
Railway historians and modellers adopted Cox’s unofficial model designation, and it
remains in use.
BREAK-IN
Don’t break in to anyone’s layout room to steal their SW1200RS. Just buy more for
yourself. But this isn’t about that kind of break-in.
Every locomotive needs a break-in period. Your SW1200RS has been tested at our
factory for about two minutes. That is not enough time to get the gears to mesh nicely
or to even out any jerky operation in a new motor. We suggest that, after reading this
manual, you put your SW1200RS on a test loop and just let it run in each direction for
an hour or two. Fast and slow.
There already should be enough grease in the gearbox so you don’t need to add any.
Just let the thing run.
HOW TO HOLD YOUR SW1200RS
The SW1200RS has numerous very delicate parts. If you want to back date it to be
the quality of a model produced in 1978, then rip all the parts off and handle it like
a pigskin going for a touchdown. We’re assuming you don’t want to do that, so the
SW1200RS should be picked up carefully. The fuel tank and the middle of the long hood
are both easily accessed and well balanced — if your hands are big enough, the best
way to pick up the unit is to grab it from above with your thumb and forefinger on either

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side of the lower edge of the fuel tank. Always make sure your hands are free of shmutz
before touching your engine.
If you are taking your SW1200RS to the club all the time and regularly handling it, stuff
will break off. Sorry. The little bits are made of plastic and metal with glue, which is all
a bit fragile. We attempted to make the small parts out of unobtainium and use Steady-
State Micro Welding to install them. Unfortunately, the unobtainium was unobtainable.
We suggest wrapping your SW1200RS in a plastic bag before placing it in the packaging
or in your holder so you can catch bits that fall off. White glue is the recommended
adhesive for reattaching the bits, although you can also use CA if you are very careful
and very brave.
CHECKING AND ADJUSTING YOUR LOCOMOTIVE
We try and make sure that every locomotive is perfectly up to spec before it leaves the
factory, but if Jason or Bill was in the factory when your model was being assembled
there may be a couple of bugs. They are always breaking stuff. Doing a quick pre-
service check will solve most operational glitches.
• Check to see that all wheelsets are correctly in gauge using an NMRA RP-2
Standards Gauge. Should any of the wheelsets be out of gauge, then remove the
affected wheelset from the truck by prying off the bottom lid of the gearbox with a
small flat screwdriver and then spreading apart the sideframes. The wheelset can
be regauged by grabbing each wheel and twisting. Reverse the steps to replace
the wheelset, and ensure the gearbox cover is snapped into place before placing
it on the track.
• Check that all underbody piping and appliances are firmly installed and clear of
the track. Of particular note are the air hoses on the ends of the locomotive and
both coupler trip pins. Bend up any low coupler trip pins so they don’t interfere
with your switches and crossings. We recommend using Kadee part #237 (Trip
Pin Pliers) or Micro-Mark part #80600 (Trip Pin Bending Plier).
• Make sure that the trucks swivel freely and without binding. If they catch on
anything, check to ensure that the ends of the trucks don’t bind against the steps.
If they do, see that everything is firmly installed.
MISSING OR DAMAGED PARTS
If you open your SW1200RS box and discover that something has obviously been
bumped in transit and is damaged, please contact us. We know that some of you don’t
like the idea of human beings touching your models, but if it is a matter of gluing an
exhaust stack back on you can do it yourself in less than a minute with a drop of white
glue. If you really want to send your model back to us for us to install that, we would be

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happy to. But if you do send it back to us for us to put that one part back on and other
stuff falls off when we send it back to you, then tough tooties. We’re not fixing it again.
If you see some grab irons are missing and they are not floating around the packaging,
let us know and we will send you replacements. More information about our limited
lifetime warranty can be found towards the end of this manual.
REMOVING THE SHELL
If you need to open up your SW1200RS (to install a crew, install a decoder, etc.) it is
NOT like our previous models, so please read carefully. In fact, we suggest that you
never open your SW1200RS for any reason, unless you are requested to do so by CSIS.
On second thought, that is actually pretty likely (you don’t want to know what we put in
there) so you will need to follow these steps:
• Your locomotive is quantum linked with its counterpart in a mirror universe.
Unfortunately, the model in the mirror universe has no detail parts. Should any
detail parts on your model fly off, the Tantalus Field in the mirror universe will
automatically retrieve those parts and install them on your model’s counterpart.
That means they are gone for good, or at least until molecular transporters or
TOMTIT machines are invented. If you don’t understand any of this paragraph,
just please remember that DETAILS VERY VERY SMALL. CAN BE LOST EASY.
• To that end, please make every effort to ensure nothing flies away. We normally
suggest you work in a room with everything white – walls, floor, ceiling,
workbench, tools, clothes – but just to be safe we advise that you also work in a
pressurized environment that looks like the inside of the VIA Turbo. Painted white.
And then invite us over. Please?
• Turn the locomotive upside down in a
foam cradle (painted white, of course)
and remove the two INNER screws
behind the cab (not the two that hold the
end pilot and steps) (1). Once removed,
turn the locomotive back on its wheels
and remove the 4 handrails attached to the cab (two long hood rails and two
step rails) (2). Then tilt the locomotive cab backwards (as though the engineer put
an impulse engine into the prime mover and went forward) and remove the cab
from the body (3).
• Remove the fuel tank by firmly pulling it down towards the rails (4). It’s press fit
so it will be snug, but will come loose. Be mindful of the piping and other details
on the sides of the fuel tank. Please remember the Tantalus Field.
continued ...

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• Turn the locomotive back on its roof and
you may see the 5 tabs holding the long
hood shell onto the body (two on each
side, one under the front air intake). They
are kind of hidden, or you may have kind
of broken them. Push the two tabs closest to
the cab inward (5), then slowly tilt the hood
forwards towards the front to disengage them. Push the remaining tabs on the
side of the long hood inward (6) and tilt a bit more to disengage (7). Don’t tilt
too far, or you’ll break the front tab off (provided you have not broken it already).
Once the side tabs are all disengaged, the front tab should slide out (8) and your
shell will be free to roam the prairies of Saskatchewan (9). Ok, maybe we got a
little carried away there.
• Any requests for replacement hoods or cabs because you broke the little tabby
things will be met with laughter followed by a very polite suggestion that you find
a nearby lake and jump into it.
OPERATION – DC (SILENT)
If your SW1200RS locomotive is not equipped with a sound decoder, it should function
like most other HO scale locomotives. Put it on the track. Give it some juice. Watch it go.
If you are new to the hobby (or just like to occasionally “play trains”) and you have a
DC-powered train set, please contact us before operating your SW1200RS as it may not
be safe (for your engine and/or your wallet) for you to use your controller.
Some train set throttles put out a very high maximum voltage that is not suitable for scale
model trains. The maximum recommended voltage is 16 volts DC. Similarly, controllers
designed for large scale trains put out a much higher voltage than your SW1200RS can
handle.
If you use a train set throttle or a throttle designed for large scale trains, your locomotive’s
circuitry may end up looking like a bag of popcorn left in the microwave after you
accidentally punched in an extra digit into the timer. In such situations, we’ll try our
best to fix it for you. But we may have to charge you for the replacement parts and/or
the labour involved. That’s because you didn’t read this bit of the manual. In DC, the
number boards are always on and the headlights and ditch lights (when equipped) are
directional. The class lights are installed and wired, but they will not work in DC.
INSTALLING A SILENT DCC DECODER
The SW1200RS contains a motherboard specially designed for our decoders. This is
connected to the track, motor and lighting outputs. A blind plug is attached to the
motherboard using a 21-pin connector. To install a decoder, remove the blind plug and

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install a 21-pin decoder. Your chosen decoder should have eight function outputs.
At the time of writing, we recommend only the following 21-pin decoder:
• ESU #54615 - LokPilot V4.0 DCC with 21MTC
We feel the 21-pin connectors are superior because there are enough pins to ensure that
all your lighting functions are connected. The necessary resistors are included on our
ESU-designed motherboard so you don’t have to futz around with resistors. Just plug in
the recommended decoder and you have DCC. We know some of you prefer a different
brand of decoder, but we honestly can’t help you install it or map the functions.
ESU has made an SW1200RS function mapping which can be downloaded into their
non-sound decoder (54615) so that the function buttons and motor control are exactly
the same as our factory-released sound versions. This should be available for download
on the SW1200RS page in the Support section of our web site. If it isn’t, bug us. You
will need an ESU LokProgrammer to write the function mapping to the 54615 decoder.
If you don’t have a LokProgrammer, you can adjust CVs in the usual way.
We will be selling SW1200RS sound decoders separately; if they aren’t on our web site
by the time you read this, call Dan Garcia at the office and yell at him. But yell nicely
please.
INSTALLING A DIFFERENT BRAND OF SOUND DECODER
Don’t.
INSTALLING BATTERIES, RADIO AND A NEAT-O APP TO CONTROL THEM
Really… Don’t.
ADD COMPATIBILITY TO 1970s TYCO AND LIONEL CONTROLLERS
Open model. Take out guts. Close model. Push with hand.
OPERATION – DC (SOUND)
To operate your sound-equipped SW1200RS locomotive on a DC layout, just give the
throttle some juice. The engine will start up once sufficient voltage has been reached
(around seven volts). See the note above (in Operation – DC (Silent)) about using train-
set or large-scale throttles. With DC layouts, you have very little control over the sounds
of your model.
WARNING: If you have purchased a sound-equipped SW1200RS and
you operate your trains with a Model Rectifier Corporation RailPower
1300 DC controller, stop what you are doing immediately. No Put Train
On Track. The RailPower 1300 is notorious for voltage spikes and it WILL
destroy your locomotive. There is no “if” about it. We will not repair any

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SW1200RS destroyed by a 1300 or any other “train set” DC controller.
“Train set” DC controllers should not be used with sound-equipped
locomotives. Buy one less sound-equipped locomotive (from another
brand) and use the money to buy a proper controller instead.
The only lights that work in DC are the headlights, ditch lights (when equipped) and
number boards. You can’t turn on the class lights in DC. Some throttle manufacturers
produce special doo-dads which are meant to trigger the sounds in locomotives on DC
layouts. As we have no involvement in the development of those doo-dads, we have
absolutely no idea how they will affect your SW1200RS, for good or for ill. As always,
we’ll try to help you fix your SW1200RS if one of these doo-dads turns your locomotive’s
circuitry into something akin to burnt toast, but we can’t guarantee we’ll be able to.
It is usually at this point in the manual that Jason inserts a gentle dig at his fellow modellers
who won’t switch from DC to DCC. The rest of the staff have repeatedly reminded
him what happened the last time he did that. Something about being kidnapped by a
band of journeymen from the masons’ guild and being labelled a warlock. He still has
nightmares about it. As long as we can keep reminding him of this event, he’ll be nice
to DC modellers. However, Josh is the one writing this manual and he thinks DC is for
YIntaghs. Hab SoSlI’ Quch!
For those of you with ridged foreheads who are feeling deeply insulted, we are pleased
to inform you that Josh has now been sacked.
OPERATION – DCC WITH SOUND
We go to extreme lengths for accuracy, in sounds as well as in looks. Our sound decoders
are LokSound Select decoders by ESU, programmed with sounds we recorded from…
erm… a GMD-1. The prime mover is the same. The hood is the same. The exhaust stacks
are the same. It sounds the same. So you can rest assured that the sounds are bang-on
accurate. We have upgraded the decoder to include ESU’s Full Throttle.
As we do for all of our sound decoders, we recorded the prime mover under load – it
was hauling loaded grain hoppers. Locomotives sound a lot different when they are
working. If you have decoders from other manufacturers in your locomotives you might
want to check out the available line of Rapido decoders on our web site. All of our
decoder sounds were recorded under load and we simply can’t stand decoders that
don’t have this feature.
More detailed decoder instructions, including all sorts of weird CV settings we don’t
understand, can be found in the ESU Loksound Select decoder manual. This is available
for download on the SW1200RS page in the Support section of our web site.

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LOCOMOTIVE ADDRESS
Your Rapido SW1200RS comes from the factory with a decoder address of 3. We’re not
sure the origins of this, but we have a feeling it’s related to the origins of video games
when you had to turn the dial on your television to Channel 3 in order to experience
the magic and wonder. That’s why your SW1200RS locomotive can, in fact, play Pong.
Sorry, we mean “APF TV Fun” for those of us who couldn’t afford the real Pong.
We suggest if you are using DCC control that you first test that the locomotive responds
on address 3. Once you have verified that the locomotive is responding you should
assign it a unique address (we suggest the road number of the locomotive) before going
any further. This can be done either on your programming track (recommended) or on
the main if your system supports programming on the main. Be aware however that if
you do program the locomotive on the main and you have any other locomotives on
your layout assigned to address 3 (the normal default address for new locomotives) that
ALL of them will likely also be changed to your new address! Also be aware that if you
give your locomotive a four-digit address it will not work at all if you try to run it on a
friend’s DC layout.
Also please keep in mind that some DCC systems do not have sufficient power to
program sound-equipped locomotives on the mainline. If your sounds do not operate
correctly on a Digitrax DCC system, this likely means that you need to clear the memory
on your system, achieved by “clearing slot #36.” A basic summary of how to do this can
be found on the SW1200RS page in the Support section of our web site. More detailed
information can be found on the Digitrax web site.
If you have a really old DCC system, you may find that this locomotive won’t work at
all – nor will many other new models. Go update your DCC system to a newer version.
Your computer is updated regularly. So is your cell phone. Your DCC system should be
updated as well.
TURN ON THE SOUND
Press F8 and you will hear the SW1200RS startup sequence followed by the sound
of it idling. You can adjust CVs to prevent the locomotive from moving until the startup
sequence has played out. We aren’t keen on this feature so we disabled it. Refer to a
full ESU LokSound Select decoder manual for more information on how to put it back.
You can download it from the SW1200RS page in the Support section of our web site.
The feature is called the “Prime Mover Startup Delay” and at the time of writing it was
on page 35 of the ESU manual.
If you press F8 when the locomotive is already moving, it will skip the startup and the
sound will just turn on. Press F8 again to turn the sound off.
Note that if you are listening to your SW1200RS idling nicely and then you select
another engine with your throttle, your locomotive still thinks F8 is pressed so it will keep

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idling along. However, if someone else selects your locomotive’s number and F8 isn’t
pressed on his or her controller, the SW1200RS will promptly shut down. He or she will
need to press F8 again.
“She?” you ask. “You mean there are female model railroaders?” Yes there are and you
better believe it. We believe the female contingent of model railroaders is expanding
more rampantly than dandelions on your unmaintained lawn every spring, especially
if you live in Rankin Inlet. So the next bit of this manual is a “women’s interest” section
specially tailored for the women who have bought this locomotive.
FUNCTIONS
F0 Headlights F10 Turn Off Number Boards
F1 Bell F11 Cab Light
F2 Horn F12 Switching Mode
F3 Curve Squeal F15 Brake
F4 Full Throttle F20 Sarco Valve (Spitter) – Slow
F5 Doppler Horn F21 Sarco Valve (Spitter) – Fast
F6 Ditch Lights (if equipped) F22 Sarco After Shutdown
F7 Dim the Headlights F23 Brake Set/Release
F8 Startup/Mute/Shutdown
F9 Class Lights
FUNCTIONS: MORE INFORMATION
F1 Bell
We have used a fantastic recording for our SW1200RS. We polled a bakers’ dozen
of railroaders and came to the conclusion that the bell ring rate is firmly set to “as long
as it makes noise.” Every engine seemingly had a different bell ring rate. We chose a
nice one.
F2 Horn
We loved our last horn recording so much, we decided to use it again! To get a short
“toot” just tap F2 or your “HORN” button. If you hear a long tail-off you are tapping for
too long. If, no matter what you do, you just can’t get the darn thing to make a short
“toot,” switch to NCE. The default horn is a K3L, but we also have an M3H on the
decoder. Refer to “Horns” below.
F3 Curve Squeal
Since it was never possible for an SW1200RS (or any road switcher for that matter)
to SILENTLY go about working tight curves and switches without waking up half the
neighborhood, we’ve included curve squeal for these hard-working road switchers.
Press F3 for curve squeal. If your DCC system supports latching on F3, the curve squeal
will continue as long as F3 is pressed. If not, you need to press once to turn on the squeal
and press again to turn it off.

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F4 Full Throttle
ESU’s “Full Throttle” feature allows you to play the prime mover of your SW1200RS like
a musical instrument, even if you’ve never played a musical instrument before. When
you press F4, you turn on “drive hold.” This keeps the speed of the engine constant at
whatever speed step your throttle happens to be on. Then as you increase the throttle,
you hear the prime mover revving up. This allows you to simulate hauling a heavy load.
On the prototype the prime mover would be up at 7 or 8 while the engine is moving
slowly. If you want to shove the throttle into notch 8 and hear it slipping and struggling
as it revs up, just crank up the throttle really quickly.
“Full Throttle” is even neater when you throttle down, as it allows you to simulate
“coasting” which is such an important part of running a real train. When you press
F4 again you turn off “Full Throttle” and the engine will accelerate or decelerate to
whatever speed step your throttle happens to be on. For realism it’s a good idea to take
note of what speed step your throttle was on when you turned on “Full Throttle” and be
back at that speed step when you turn “Full Throttle” off. Otherwise your SW1200RS
may take off. Eh.
F5 Doppler Horn
We’ve sourced a gorgeous K3L recorded on a moving locomotive doing about 30MPH.
Beauty goal, eh? And on top of that, if you change your horn to an M3H (see Horns
below), your Doppler horn automatically switches to an M3H Doppler recording.
F6 Ditch Lights (if equipped)
If your locomotive comes equipped with ditch lights, this function will allow you to
activate them. Pressing F6 turns them on. Pressing F6 again will turn them off. This
process can be repeated infinitely. If you are approaching a station or an oncoming
train you can turn off the ditch lights and dim the headlights automatically by pressing
F7. You don’t want to blind anyone, now do you?
F7 Dim the Headlights
If you are approaching a station or an oncoming train you can turn off the ditch lights
and dim the headlights automatically by pressing F7. You don’t want to blind anyone,
now do you? I’m getting a sense of déjà vu. I’m getting a sense of déjà vu. Josh, you’re
fired. Josh, you’re fired.
F9 Class Lights
They do exactly what they say – these function buttons turn on the class lights. SW1200RS
locomotives only use white class lights. The SW1200RS is not often called upon to lead
two sections of The Canadian, so the greens aren’t needed. And the SW1200RS isn’t
normally pushing commuter trains, so the red lights aren’t needed. If you want to press
your SW1200RS into AMT service pushing commuter trains, just shmear the class lights
with a red crayon.

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F10 Turn Off Number Boards
The number boards are lit by default, a big improvement over many of our early models.
It was annoying when you’d lose power because of a short somewhere else on the layout
and then you had to go through the tedious task of turning your number boards back on.
If you really want them off, press F10. We suggest you be a rebel and just leave them
on. You would be a Rebel WITH A Cause. And that cause is lit number boards.
F11 Cab Light
No crew should have to write orders in the dark. Or eat their lunch in the dark. Or
venture into the depths of the cab fridge (included on all SW1200RS models) in the
dark. So give your crew some light by pressing F11. Pressing it again turns it off. We
won’t judge if you want to have a disco light show in the cab
F12 Switching Mode
If you press F12, the headlight and rear light will both be on dim. This is appropriate
for switching operations or for running light on the mainline. Press F12 again to turn off
the switching mode lighting.
F15 Brake
In 15 years of making model trains we have met about three people who use the brake
feature on our locomotives (we found a new one last year). So we’ve shoved this to a
higher function button. If you are one of those three people, you are clever enough to
remap this feature onto a lower function button by following the instructions in the full
ESU Select Decoder manual, which can be downloaded from the SW1200RS page of
the Support section of the Rapido web site.
Functions F16-F19
These are not used. Don’t press them. Also don’t lick your locomotive.
F20 and F21 Sarco Valve (Spitter)
These functions turn on or off the Sarco Valve. On the real SW1200RS, it’s always
going. But you often can’t hear it from a distance. In contrast, if you are close to the
engine you can hear the Sarco valve pretty prominently. We feel that on many sound-
equipped engines, the Sarco Valve is way too loud. So we’ve included two versions of
it, controlled by functions. You can choose whether or not you hear the Sarco Valve, and
you can choose how fast you want it to spit.
If you press F20, the Sarco Valve will be heard intermittently. If you press F21, it will be
heard less intermittently. Make sure you turn off F20 first.
If you have a silent SW1200RS and you want to recreate the Sarco Valve effect, please
aim away from the models. Your SW1200RS warranty does not include malfunction
due to accumulated saliva. Your locomotive is also not equipped with a real Sarco valve
either. Sorry.

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F22 Sarco After Shutdown
On real engines you can hear the Sarco Valve after the engine shuts down, but again it
is not really audible unless you are right beside it. So the default for this is “off.” If you
want to hear the Sarco Valve spit for a minute after shutdown, make sure F22 is pressed.
F23 Brake Set/Release
This function turns off the brake release and brake set sounds when you start or stop
moving, respectively. It has no effect on the function of the engine — it just affects the
sounds.
HORNS
Canadian National and Canadian Pacific each used different horns, and we’ve included
both recordings since the team at Rapido are all about fair play. But since we had to
pick one, the default for all models is the Nathan K3L, with the other being a Nathan
M3H. You’re more than welcome to switch the horn to whichever you like the sound of,
and you can do so by changing the value of CV48. For the record, CP used the K3L and
CN used the M3H. The little CN horn on your model may look a wee bit like a K3L, but
how about them Jays?
• CV48-0 Nathan K3L (Default Horn)
• CV48-1 Nathan M3H
Note that you can only change the horn on a programming track or using a LokProgrammer.
SOUND VOLUME SETTINGS
The sound volumes on your decoder have been pre-set at the factory to levels that we
found comfortable on our test tracks.
Sound levels are very much a matter of personal taste (especially if you are going deaf
like we are), and what sounds great in one layout environment may sound too loud or
too soft in another. Fortunately, the sound levels can be easily adjusted to best suit your
own requirements and we recommend that you experiment with different settings if you
don’t care for the default levels.
To set the volume levels go into the program mode on your DCC system (refer to your
system’s manual for instructions on how to do this as each system is slightly different);
enter the desired CV number; then enter the desired levels. Note that this can be done
either on a programming track or on the main (ops mode) if your DCC system supports
programming on the main.
We strongly recommend that you keep notes on which settings you have changed and
which values were used. If you ever need to do a reset on the decoder (see “Factory
Reset” below) then having good notes will allow you to easily re-enter any changes that
you might want to keep.

16
VERY IMPORTANT: Before you change any of the volume control CVs,
please make sure that CV 32 is set to 1. CV 32 is used as an index
selection register and if you don’t set it first then we are not responsible
for your resulting rage and the fact that you will probably throw the
locomotive against the wall in frustration.
SW1200RS SOUND VOLUME SETTINGS
FUNCTION CV DEFAULT RANGE YOUR VALUE
MASTER VOLUME 63 192 0-192
DIESEL VOLUME 259 128 0-128
HORN VOLUME 275 128 0-128
BELL VOLUME 283 50 0-128
BRAKE SET/RELEASE VOLUME 347 40 0-128
SHORT AIR LET OFF VOLUME 363 128 0-128
DOPPLER HORN VOLUME 379 100 0-128
FAST SARCO VALVE VOLUME 371 80 0-128
SLOW SARCO VALVE VOLUME 387 80 0-128
SARCO VALVE AFTER SHUTDOWN VOLUME 395 80 0-128
CURVE SQUEAL VOLUME 403 128 0-128
FACTORY RESET
On your SW1200RS, you perform a factory reset by entering a value of “8” into CV 8.
Note that this will cause all of your new volume and motor settings to be lost, so you will
need to reprogram any settings that you want to keep. What do you mean, you didn’t
take any notes? WE JUST TOLD YOU TAKE NOTES. You’re out of the band.
You can NOT lose all of the pre-recorded sounds on your SW1200RS decoder by doing
a factory reset. However, after performing a factory reset your SW1200RS may begin
to do the Watusi and recite lines from Apocalypse Now. If that happens, you have
probably lost your mind. Those elephants are not real. Lie down, relax and maybe the
drumming noise in your head will stop. Dum-dum-dum-dum. Dum-dum-dum-dum.
AWESOME SLOW SPEED THINGY
There is an awesome trick that you can use to get even better slow speed running
and smoother operation. It’s called the Automatic Motor Tuning Feature. This feature
will automatically adjust the Back-EMF in most cases and give you phenomenal slow-
speed performance. WE HIGHLY RECOMMEND YOU DO THIS FOR ALL YOUR ESU-
EQUIPPED RAPIDO ENGINES.
In order to use this automatic adjustment, you need to use Ops mode programming, i.e.

17
programming on the main. Make sure your locomotive is in “forward” and that you have
lots of room in front of it on your mainline. You may have to set up pylons or a work
block to keep other errant model railroaders from entering your territory. Set CV 54 to
a value of 0. Then get out of programming mode and turn on the bell (press F1). We’ll
say this again: Make sure you have plenty of room in front of your locomotive and it is
not headed for the layout edge and the basement floor!!!
Your SW1200RS will quickly take off at full speed and suddenly stop. All the HO scale
beverages in the HO scale cab fridge will fall out. After that, you’ll have fabulous motor
control. And a messy cab. If you ever have to reset your locomotive, you can do the
automatic adjustment thingy again – it just takes a few seconds.
MORE INFORMATION
While addressing the features that most modelers will need for normal operation, these
instructions have covered just a small number of the many customizable features of
your ESU LokSound decoder. For advanced users who want to more fully explore the
capabilities of the decoder we suggest downloading the ESU Loksound Select decoder
manual. This is available on the SW1200RS page in the Support section of our web site.
LIMITED LIFETIME WARRANTY
We will do our best to solve any problems or issues that you may have with your
SW1200RS locomotive. If your locomotive has any defects that originate from the
factory, we will repair your locomotive using new components or replace it outright
should a repair not be possible. However, we can only replace your locomotive while
we have additional ones in stock. We normally keep spares for up to six months after a
model is released. If you are like most of us and – after purchasing this locomotive – you
dismissed it to the dungeon deep beneath your layout and are now just discovering it
35 years later after you heard it crying “run me”, then you are on your own if there are
any issues. Jason is long retired and still trying to repair our sleeping car, Edmundston.
The rest of us have moved to Tonga.
There are a number of things that this warranty cannot cover. If your SW1200RS arrives
with a couple of loose grab irons or underbody bits, there is a very good chance that
you can effect a repair in less time and effort than it would take to contact us. Don’t be
afraid to do some model railroading! White glue, such as Weldbond, works wonders
for securing all sorts of parts and will not mar or damage your paint. However, if parts
are missing that is another story – call us or send us an email and we’ll send you some
replacements.
Of course, damage caused by running your SW1200RS at full speed around a
15”-radius curve along the edge of your layout, modifying your SW1200RS to work
off rocket fuel, not modifying your SW1200RS to work off rocket fuel but still filling it
with rocket fuel, strapping your SW1200RS to a firecracker for an entertaining YouTube

18
video, or any other damage caused by you that we haven’t been able to cover here is
not covered by the warranty. However, if catastrophe does strike and your locomotive
gets damaged, please give us a shout and we’ll do our best to help you out. Yes, even
if it was your fault we will try our best to fix your locomotive for you.
Don’t be shy!
If you really hate your SW1200RS, please feel free to tell the internet model train forums
of the world. Please remember that our company name is spelled T-Y-C-O and we are
based in Woodbury Heights, NJ.
ACKNOWLEDGEMENTS
Many people have provided their kind assistance in order to ensure that our SW1200RS
is an amazing model. Special thanks go to Dan Dell’Unto, John Eull, Ken Goslett, Dave
Love, Steve Lucas, Dave Minshall, Bob Merriam, Jakob Mueller, Brian Schuff, and the
Ontario Southland Railway. We also cannot forget the invaluable services of Richard
Longpre for providing us with the French translations in this manual. Any mistakes in
this manual are all Josh’s fault. But as we’ve just fired him three times you can’t really
blame him.
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