M.T.H. Blue Comet User manual

R
ELECTRIC TRAINS
MTH BLUE COMET
STEAM ENGINE
OPERATING INSTRUCTIONS
Thank you for purchasing the MTH Electric Trains die-cast Blue Comet
steam locomotive. This ¼” scale reproduction of the famous Blue Comet
locomotive measures over 22” in length and weighs over 9 pounds. Despite
its scale size, the locomotive is capable of operating on O-42 3-rail track
with any compatible AC transformer, (see page 34 for a complete list of
compatible transformers and wiring instructions) and is completely
compatible with most other 3-rail locomotives, rolling stock and
accessories.
The locomotive and tender are equipped with several deluxe features that
are simple and fun to operate. Each feature is described among the
following pages which should be read before the engine is operated. For
those of you who can’t wait to get started, the Quick Start Operating
Instructions, found on page 3, should be read so that you understand the
basics of the operating system. Those features marked for 2 and 3-rail
engines are available in both types of engines. Features not marked as such
are only available in the 3-rail version.
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Table Of Contents
QUICK START - BASIC OPERATION(All 3-Rail Models) 3
PROTOSMOKE™ UNIT OPERATION 4
PROTOSOUNDS® OPERATING INSTRUCTIONS 5
ProtoSound® DCRU® Reverse Unit Operation (All 3-Rail Models) 5
Whistle Operation 6
Bell Operation 6
ProtoCoupler™ Operation 7
Enhanced Neutral Steam Sounds 8
Squeaking Brake Sounds 8
Tips On Using The Squeaking Brake Sounds 9
Passenger Station Sounds (PFA) 10
Activating and Triggering Passenger Sounds 10
Tips On Using PFA Features 15
Self-Recharging Battery Backup System 16
Replacing The ProtoSound® Battery 16
ProtoSound® Volume Adjustment 17
USING “RESET" TO PROGRAM PROTOSOUNDS™ 18
Entering RESET Options 18
Setting The Engine Volume 19
Programming For A Separate Bell Button Controller 20
Programming For Squeaking Brake Operation 20
Programming For Whistle In Neutral Operation 21
Programming For ProtoCoupler™ Operation 22
Programming For PFA Operation 23
Activating Remote Lockout Control 23
ResettingAll ProtoSound® Options To Factory Default 24
REVERSE UNIT LOCK-OUT OPERATION 25
Locking The Engine Into Forward or Reverse 25
Unlocking The Engine 25
Locking The Engine Into Neutral 25
OIL & LUBRICATION INSTRUCTIONS 27
TRACTION TIRE REPLACEMENT INSTRUCTIONS 28
LIGHT BULB REMOVAL & REPLACEMENT 29
TROUBLE SHOOTING PROTOSOUND® PROBLEMS 30
ProtoSound® RESET Feature Chart 33
Transformer Wiring Chart 34
SERVICE AND WARRANTY INFORMATION 35
HOW TO GET SERVICE 35
LIMITED ONE YEAR WARRANTY 35

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QUICK START - BASIC OPERATION
The MTH Blue Comet contains state-of-the art electronics with several
built-in automatic features for incredibly realistic operation. Despite these
advanced features, the Blue Comet is easy to operate with any compatible
standard AC transformer (see the compatibility chart on page 34). All
models are equipped with an operating smoke system that should be primed
with smoke fluid before operating. Adding 15 - 20 drops of fluid through
the smoke stack should be sufficient. If you choose to not prime the units
with fluid,turn the smoke unit switch located under the trailing truck to
the OFF position. (See Figure 1) This will prevent any damage from
occurring to the smoke unit when running the engine without a primed
smoke unit. For more information see the section on page 4 on Smoke Unit
operation.
The Blue Comet model is controlled by
a ProtoSound® DCRU® electronic
reverse unit. The reverse unit operates in
the same manner that all reverse units
function by using forward, neutral and
reverse states that are entered each time
the throttle is turned on and off or by
using the transformer direction switch (if
so equipped).
The reverse unit is designed to ignore dirty track, dead spots on switches
or minor short circuits without
disrupting the engine operation,
even at slow, prototypical speeds.
Before the engine can be operated
however, the reverse unit plug that
extends out of the tender must be
inserted into the receptacle at the back of the boiler cab as seen in Figure 1.
Once the plug is inserted, the throttle on the transformer can be advanced.
You will see that only the engine’s lights come on and that on ProtoSound
equipped engines, two dings from the sound system will chime followed by
the steam compressor pump sounds. The engine does not run. This is
known as the RESET state and is explained in more detail beginning on
Page 6. The ProtoSound® DCRU® will not power the motor until the
throttle is turned OFF and then ON again. At this point, the engine will
now function just like any other electronic or mechanical E-unit.
Plug Tender Plug Into
Boiler Socket At Back Of Cab
Use First Hole For O-42 Operation
Use 2nd Hole For Display and 96 Inch
or larger diameter curves
Figure 1: Pluggin in the tender harness
RESET
Neutral
Reverse
Neutral
Forward
Figure 2: ProtoSound® DCRU® Cycle Phases

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PROTOSMOKE™ UNIT OPERATION
(2 and 3-Rail)
The Blue Comet contains a self-powered smoke unit that outputs a steady stream of smoke
through the smoke stack on the roof of the engine. The ON/OFF switch located next to the
trailing truck must be in the ON position in order for the smoke unit to function. See Fig.
2 below.
The smoke unit is essentially a small heating
element and wick which soaks up and then “cooks" a
mineral oil-based fluid that omits a harmless smoke.
The smoke is then forced out of the stack via a small
electric fan which runs at a constant speed. However,
the smoke intensity can be varied by increasing the
transformer voltage setting. The higher the setting,
the more intense the smoke output.
For best results, we recommend that you add 15 -
20 drops of ProtoSmoke™, Seuthe, LGB or LVTS
fluid before you run the engine. If you don’t choose
to add the fluid, then the smoke unit switch should be turned off. Failure to either add the fluid
or turn the switch off could lead to damage to the smoke unit heating element and or wicking.
Add the fluid through the smoke stack hole as indicated in Figure 3. After adding the fluid,
gently blow into the stack to eliminate any air bubbles. Do not overfill the unit as overfilling
can cause the fluid to leak out and coat the interior engine components. When the smoke
output begins to diminish while running the engine, an additional 10-15 drops of smoke fluid
should be added or the smoke unit switch should be turned off. When storing the engine for
long periods of time, you may want to add at least 15 drops of fluid to keep the wick soaked
with fluid and prevent it from drying out. After removing the engine from storage, it is
advisable to add another 25 drops of fluid, letting the wick soak up the fluid for 15 minutes
prior to operation.
SMOKE UNIT MAINTENANCE
(2 and 3-Rail)
CAUTION: Operating the engine without smoke fluid
and with the smoke unit switch in the ON position can
damage your smoke unit wick, causing the wick to
become hard, blackened and unabsorbant around the
heating element. When this occurs, it may be difficult
for the wick to soak up the smoke fluid resulting in poor
or no smoke output. If that occurs, we recommend that
you inspect and/or replace the wick taking care to not
run the engine without fluid in the future. You can
inspect the wick to see if it needs replacement by
removing the smoke unit inspection cover from the body
as seen in Fig.4. After removing the chassis and
inspection cover screws lift the inspection plate away
and inspect the wick. If the wick is darkly discolored and hard, it should be replaced.
Smoke Unit
On/Off Switch
Figure 3: Smoke Unit Switch
Smoke Unit
Circuit Board
Mounting Screws
Smoke Unit Frame
Mounting Screws
Figure 4: Inspecting The Smoke Unit

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PROTOSOUNDS® INSTRUCTIONS
The MTH ProtoSound® digital sound and train control system provides
the operator with unprecedented realistic operation on your model railroad.
In addition to actual Blue Comet engine, CD-equivalent 16-bit digital
sounds, you get the following features:
*
Built-In ProtoSound® DCRU® Reverse Unit * Authentic Steam Whistle Sound*
Authentic Steam Bell Sound* Squeaking Brake Sound* Passenger Station
Sounds* Operating Remote Controlled ProtoCoupler™* Self-Recharging Battery
Back-Up System With Automatic Battery Shut-Off* Remotely Controlled
Reverse Unit Lock-Out* Remotely Adjustable Steam Engine Chuffing Volume* *
Authentic Steam Engine Neutral Sounds*
Each feature is described among the following pages. Though the system
is easy to use, we encourage you to read the instructions thoroughly.
PROTOSOUND® DCRU® REVERSE UNIT
As mentioned in the Basic Operating section, the engine is controlled by a
DCRU® reverse unit that contains the standard forward-neutral-reverse
states found on most reverse units. However, as described earlier, when
power is first applied to the track, the reverse unit begins in RESET or what
seems like a neutral state. Power must be interrupted again to get the
locomotive to enter the forward state. It is this first RESET state that gives
ProtoSound® its unique, remote controlled functions. The system will enter
RESET whenever power to the track is off for three or more seconds.
NEUTRAL will be referred to as the state between Forward and Reverse.
ProtoSounds® is equipped with a microprocessor, that, depending on the
amount of memory it is allotted, allows the user to utilize several remotely
activated functions. In the simplest terms, ProtoSounds® has its own
“Computer" controlling these functions. In fact, the power of this
microprocessor is the same as that of a 286 desktop computer! In order to
access many of these remotely controlled functions, the user must be in the
RESET state to do so. RESET is entered anytime power to the locomotive
has been off for more than 3 to 5 seconds. When the engine first enters
RESET, the microprocessor initiates a system check to determine if the
system, transformer and engine are operating correctly. This takes
approximately 2.2 seconds during which you will hear the engine’s startup
sounds begin. In order for ProtoSounds® to properly initiate the system
check, do not advance the transformer throttle past 10 volts when you first

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enter RESET, wait for the diesel startup sounds to begin and then slowly
turn the transformer throttle to the off position and then back on again to
enter the forward phase. Interrupting the power too quickly may cause the
system to re-enter RESET (signaled by two dings of the bell). Should this
happen, wait longer before interrupting the power to enter the Forward
phase.
ProtoSounds® comes with several programmable functions, including
remote Steam Chuffing Volume Adjustment, Separate Bell Button
Operation (pre-programmed at the factory), Whistle In Neutral Operation,
ProtoCoupler™ On/Off Control, Squeaking Brakes and Passenger Station
or Freight Yard Proto-Effects. Each of these features are described in more
detail later. You will notice that when in RESET, your engine will not
respond to the whistle button with a horn blast or continuous bell ringing.
In fact, when in RESET and the whistle button is depressed, only one single
bell chime will be heard each time the whistle button is pressed. If you
don’t want to configure or change your locomotive using any of these
programmable features, simply leave RESET and wait 2.2 seconds before
interrupting the power to put the engine in forward. After you leave
RESET, your engine will operate normally in all the direction states of
forward, neutral and reverse. Remember though, once power is turned off
for more than 3 seconds, the next time power is applied to the track, your
engine will be back in RESET.
WHISTLE OPERATION
Your Blue Comet ProtoSound-equipped engine is equipped with a digital
recording of a steam whistle. The whistle sound can be activated anytime
the engine is in forward or reverse by pressing the whistle button on your
transformer. The whistle will continue to blow as long as the whistle button
is depressed. The whistle will not function in RESET and must be
configured through a RESET option to allow the whistle to work when the
engine is in neutral. See page 21 for information on whistle programming
in the Using RESET To Program ProtoSounds® section of this manual.
BELL OPERATION
Your Blue Comet ProtoSound-equipped engine is equipped with a digital
recording of an actual steam engine bell. The bell can be turned on or off
with any separate bell button, like the Lionel® Railsounds® No. 5906 Bell
Button, by simply pushing the button. If you don’t have a separate bell
button, the bell can be controlled through your transformer’s whistle button

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whenever the engine is in NEUTRAL. The bell will never ring
continuously in RESET (Remember NEUTRAL is the state between
Forward and Reverse). Once the bell is turned on, it will continue to ring
when the engine is cycled into forward or reverse until you press the bell
button or re-enter NEUTRAL and turn the bell off with the whistle button.
In fact, because of ProtoSounds® state-of-the-art design, the
microprocessor remembers its last command. Therefore, unless you turn
the bell off before you quit running your train, the next time you run the
engine, the bell will come on. No matter whether you come back an hour
later or a year later, the bell will begin chiming once the engine enters one
of the three directional states.
To turn the bell on using the transformer’s whistle button, turn on power to
the track and cycle the engine into NEUTRAL. Turn the throttle to 8 volts
or less (any higher voltage will arm the ProtoCoupler™) and press the
whistle button. The bell should begin chiming. To turn the bell off, press
the whistle button again. If you want to keep the bell on while running the
engine, simply interrupt the power with the transformer throttle or the
transformer directional switch and enter forward or reverse.
PROTO-COUPLER™ OPERATION
Your Blue Comet ProtoSound-equipped locomotive tender is equipped
with a coil-wound ProtoCoupler™ for remote uncoupling action. Because
the ProtoCoupler is controlled through ProtoSound’s microprocessor, it
doesn’t require an uncoupling track section or modification to your layout
to function. The three simple steps below are required to operate the
coupler.
1. Put your engine in NEUTRAL and turn the throttle all the way up.
2. Press the transformer whistle button to “Arm" the coupler. (You
will hear a “Clank").
3. After arming the coupler, press the whistle button again to open
the coupler.
When the knuckle fires
open you will hear the
buzzing of the coil energizing
and the sound of the air lines
coming apart. It can best be
HH
Ca-Clunk
Cha-Chussshhh
Put Engine In Neutral
At Full Power
Press & Release
The Whistle Button
Press & Release
The Whistle Button
Listen For The
Ca-Clunk Sound
See The Coupler Open
And Listen For The
Cha-Chusshh Sound

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described as a CHA-CHUSHHH sound. The coupler doesn’t have to be
fired in NEUTRAL. Once the coupler is armed it can be fired in Forward,
Neutral or Reverse. However, you may find that the coupler doesn’t open
when firing the coupler at high
speeds. Reduce the voltage
setting on your transformer if
this occurs and run your engine
at a slower speed before firing
the coupler. If the coupler
continues to open erratically, try
lubricating the knuckle with
light oil as indicated in Fig. 5.
ENHANCED
NEUTRAL STEAM SOUNDS
The enhanced Neutral Sounds can be automatically heard whenever the
engine is in neutral. The sounds, which include Steam Pop-Off, Steam
Blow-Down, and Steam Injector sounds occur every 2 to 30 seconds. Each
of the three sequences will play at random intervals to eliminate repetitive
and boring sequences. While the sounds are selected to play randomly by
the microprocessor, there is no guarantee that you won’t hear the same
message repeated twice or more times.
SQUEAKING BRAKE SOUNDS
ProtoSound equipped engines feature the ability to play the sound of
squeaking brakes whenever your engine slows in speed. There are two
settings for activating the squeaking brake sounds. The default setting
allows the brake sounds to play while the engine is in forward or reverse
and the transformer throttle is lowered from a high setting to a low setting
(14 volts to 8 volts or less). The second setting requires that a bell button be
used to “arm” the brake feature and is explained in more detail in the
“Activating Passenger Sounds”
section found later in this
manual. The sound itself is a
stored record on the ProtoSounds
software chip and will always
play the same brake sound for
the same three second length
Lubricate
Coupler
Knuckle
Figure 5: Lubricating The ProtoCoupler
Squeeek
Throttle Down From
High Voltage To Low
Listen For The
Squeaking Brake Sounds

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each time the voltage is reduced from high to low. Some practice may be
required to synchronize the playing of the brake sounds with the movement
of the engine. It is not uncommon for the engine to stop before the brake
sound is completed. Operators will find that by coordinating the movement
of the throttle setting from 8 volts to off will allow the engine to maintain its
movement while the brake sounds play. Note: The brake sounds will not
be heard if the transformer throttle is not set above 14 volts and/or not
reduced below 8 volts.
TIPS ON USING THE SQUEAKING BRAKE FEATURE
Because the squeaking brake feature always plays for approximately 3
seconds, it is possible that the brake sounds will play longer or shorter than
what visually seems prototypical. You will find that by practicing with the
brake feature, you can quickly determine how quickly to throttle down and
what speeds and voltage settings give you the most prototypical braking effect.
Typical users will find the feature to be a very realistic way to simulate the
sound of an engine slowing down for curves, crossings or coming to a stop at a
station, side track or switch yard. As mentioned above, you will find that
initially your engine may continue to play the brake sounds once your engine
comes to a stop or that the sounds stop prematurely before the engine comes to
a complete halt. For example, if you simply run the engine and turn the throttle
off quickly, the brake sounds will likely continue playing even though the
engine has come to a complete stop. This annoying effect can be eliminated by
simply practicing with the brake feature. In no time, you will quickly learn
how to “feather" the throttle to keep the engine moving while the brake sounds
play and then turning the throttle off just as the sounds stop. Remember that
once you stop the engine, you should turn the throttle to the off position if you
don’t want to activate the Passenger Sounds feature described later in this
manual.
The ProtoSound squealing brake feature also has the ability to simulate the
squeal of wheel flanges when your train enters a curve at high speeds. The
same brake squealing sound plays, but you don’t need to reduce the transformer
throttle to activate the squealing sounds. To play the squealing sounds as wheel
flange sounds, trigger the brake feature using either method 1 or 2 above. Once
triggered set the transformer throttle setting at 14 volts or higher. As your
engine enters a curve (or anywhere on the layout) quic[ky “flick" your
transformer whistle button about half way. This “flicking" action causes the
transformer to release a short DC signal that ProtoSounds reads as an indicator
to activate the brake sounds. The engine won’t slow down even though the
sounds play. This simulates the wheel flange squeal of a train travelling
through a turn too quickly.
Note: Consistent activation of the wheel flange squealing is determined by the
condition of your transformer’s whistle button rectifier disc. Older rectifier
discs may need to be replaced in order to play squealing sounds.

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PASSENGER ANNOUNCEMENTS (PFA)
ProtoSounds is now equipped with operator controlled passenger station
announcements, hereby known as PFA. This easy to use feature plays
digitally reproduced passenger station sounds whenever your engine stops
at a train station on your layout. No additional wires or modifications are
needed on your layout to enjoy these amazing sound effects. The sounds
themselves are randomly generated and randomly “shuffled” on the
ProtoSounds software chip. This gives the system the ability to produce
different sounds in a different order each time the PFA feature is enabled.
These different sounds are heard each time you cycle the transformer
throttle from on to off in the same manner that you would cycle the throttle
to enter the various states of forward, neutral and reverse. The entire PFA
sequence is designed to simulate the arrival, disembarking, embarking, and
departure of a train entering and leaving a train station. The sounds include
public address arrival and departure messages, passenger disembarking and
embarking sounds, conductor voices and general train station ambient
sounds. Each is described in more detail in the following sections.
ACTIVATING PASSENGER SOUNDS
Your ProtoSounds equipped engine features an operator controlled
passenger station sound set. Once activated, this easy to use feature plays
digitally reproduced sounds of a passenger station whenever you stop your
engine in the neutral position at a train station on your layout.
ARMING THE PASSENGER SOUNDS FEATURE
Before the passenger station sounds can be heard, ProtoSounds must
activate the feature so that the next time the engine enters the neutral
position, the sounds can play, The feature can be activated one of two ways.
Option 1: If you are using a separate bell button controller to ring your
bell (like the Lionel Railsounds® No. 5906 bell activation button) you can
activate the feature by
pressing and holding the
bell button for three
seconds or longer (it
doesn’t matter if you are
in forward, neutral or
reverse). You will hear
Ding, Ding
Psshhee
Put Engine In Neutral,
Forward or Reverse
Press & Hold
The Railsounds® Bell Button
For 3 Seconds
Listen For The
Start Of The Bell Sound
Listen For The
Air Release Sound
After 3 Seconds

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the bell chiming turn on and if you listen carefully you should hear an air
release sound after three seconds have passed at which time you can release
the bell button. (Note: because the air release sound is hard to hear, we
recommend that you count out a full three seconds before releasing the bell
button.) The bell will continue to chime, so if you want to turn off the bell
ringing, simply press and release the bell button a second time. If you were
in neutral when you triggered the brake feature, interrupt the transformer
throttle to enter either forward or reverse to allow the engine to begin
running. (Note: the feature will only be activated in the first direction
state you enter after triggering the feature from the neutral position. You
cannot interrupt the power twice to enter another direction state and still
have the passenger sound feature active.) Once your engine begins
running, you can trigger the sounds to begin playing whenever you enter
neutral.
Option 2 If you do not have a separate bell button on your layout, you can
still activate the feature with your transformer whistle button. To activate
the feature turn on the transformer throttle and get your engine into the
neutral position (not RESET). Once in neutral, set the transformer throttle
at 8 volts or less and press and hold the whistle button for at least three
seconds. You will hear the bell chiming turn on and if you listen carefully
you should hear an air release sound after three seconds have passed at
which time you can release the whistle button. (Note: because the air
release sound is hard to hear, we recommend that you count out a full three
seconds before releasing
the whistle button.) The
bell will continue to chime,
so if you want to turn off
the bell ringing, simply
press and release the bell
button a second time.
Interrupt the transformer
throttle to enter either
forward or reverse to allow the engine to begin running. (Note: the feature
will only be activate in the first direction state you enter after triggering
the feature from the neutral position. You cannot interrupt the power twice
to enter another direction state and still have the feature active.) Once your
engine begins running, you can trigger the sounds to begin by entering
neutral.
Ding, Ding
Psshhee
Put Engine In Neutral
At Low Power
Press & Hold
The Whistle Button
For 3 Seconds
Listen For The
Start Of The Bell Sound
Listen For The
Air Release Sound
After 3 Seconds
H

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ACTIVATING AND TRIGGERING PASSENGER
STATION ANNOUNCEMENTS
Before PFA can be heard the feature must be activated first. Activation is
accomplished by holding down the bell button for three or more seconds as
described in the Activating and Triggering The Passenger Station Sounds
section found earlier on page 10.
Once the feature is activated, PFA will be played the next time the engine
enters the neutral position. In order for PFA to begin, power must remain
on once the engine enters the neutral position. At this point ProtoSounds
has taken over control of your engine and disabled the bell and whistle
buttons from any further operator functions. In addition, ProtoSounds has
reconfigured the way the reverse unit functions by disabling the reverse unit
state during operation of the PFA feature. This forces the engine to leave
your station in the same direction it arrived. The following operator
controlled “events” control PFA’s actions and sounds.
Event 1 (Forward) While the locomotive is running in forward (or
reverse) PFA is activated by the operator pushing and holding the bell
button down for three or more seconds. The locomotive bell begins
chiming and can be left on or turned off without disabling PFA.
Event 2 (Neutral Before Reverse) The operator now interrupts the
transformer throttle to stop the engine and put it into neutral. If the throttle
setting was at 14 volts or higher, ProtoSounds will play the sound of
squealing brakes as the engine comes to a stop.
I. Upon stopping of the engine, the operator must immediately turns
the throttle back on as the engine sits in
neutral. If the bell was not turned off
after activating PFA, it now turns off
automatically.
Note: Failure to turn the throttle back on
within 3 seconds of leaving the forward phase will
disable PFA and shutdown ProtoSounds. The next
time you turn power back on your engine will be in the RESET position. See page 5
for more information.
Put Engine In Neutral
At Low Power

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II. After entering neutral, ProtoSounds will immediately play an air
release sound followed approximately two seconds later by an arrival
message. The arrival message lists the
train by name and the track it arrived on
(the track is identified as either track 1 or
track 2, alternating each time during the
current operating session). Immediately
following the arrival message, the sound
of the trains’ doors opening can be heard,
followed by a conductor’s warning to
passengers to “watch your step.” At this
point, various randomly activated ambient train stations sounds will
begin playing and replaying as long as the engine sits in this neutral
state (Neutral Before Reverse). The sounds include passenger
footsteps as they disembark, muffled voices, baggage being moved
about, crashing sound, and whistling for a taxi. In addition, several
highlight or foreground sounds play including more conductor voices
saying “watch your step”, “have a nice day”, and “baggage to the
right”.
Event 3 (Reverse) The operator now interrupts the transformer throttle
again to enter the next reverse unit phase; reverse. In an effort to enhance
realism, PFA has disabled the reverse
phase so that it doesn’t power the motors
and cause the engine to move backward.
Upon entering reverse, PFA confirms to
the operator that it has entered the reverse
state by immediately playing the highlight
sound of the conductor’s voice saying
“baggage to the right.” This is followed
by the continued ambient sounds of
passenger footsteps, muffled voices,
baggage being moved about, crashing sound and whistling for a taxi. These
sounds and the conductor highlight are randomly repeated as long as the
system remains in the “reverse” state.
Listen For Air Release Sound
And PA Arrival Message
Psshhhee
Listen For Conductor
To Say ...
Baggage To The Right
Interrupt Throttle To
Enter The Next Phase

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Event 4 (Neutral Before Forward) The operator now interrupts the
transformer throttle again to enter the next reverse unit phase; neutral before
reverse. PFA confirms to the operator that it has entered the neutral before
forward phase by emmitting two quick air release sounds. This is followed
by a public address message that the train on
track 1 or 2 (whichever track number the
arriving public address message stated) is
now boarding. Upon completion of the PA
message, two conductor voice highlights
randomly begin playing. These conductor
voices include “Welcome Aboard” and
“Tickets Please”. In addition to the two
conductor highlights, the station ambient
sounds continue and still include passenger
footsteps, muffled voices, baggage being moved about, crashing sound and
whistling for a taxi. The departing public address message automatically
repeats itself every 60 seconds with the highlights and station ambient
sounds randomly occurring as long as the system remains in the “neutral
before forward” phase.
Event 5. (Forward) The operator now interrupts the transformer
throttle again to enter the next reverse unit phase; forward. PFA confirms
to the operator that it has entered the forward
phase by playing a conductor voice yelling
“All Aboard!” Immediately after playing “all
aboard”, the sound of the doors closing is
heard. Within two seconds of the doors
closing, the locomotive bell begins chiming
and the air compressor pumps start. After
approximately 7 chimes of the bell, the
engine automatically begins moving out in
the forward phase with the bell continuing to
ring another 7 chimes before automatically turning off. Once the bell turns
off the operator regains control of the transformer whistle and bell buttons
and can ring the bell or blow the whistle as usual.
Note: When entering the forward phase of PFA, it is important to set the transformer
throttle at a high enough setting that will allow the engine to begin moving once PFA
automatically activates the motors. Otherwise, the engine will just sit still until you increase
the throttle setting on the transformer.
Listen For The
Conductor To Say ...
All Aboarrrd!!
Interrupt Throttle To
Enter The Next Phase
Listen For 2
Air Release Sounds
Psshee, Psshhee
Interrupt Throttle To
Enter The Next Phase

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TIPS ON USING THE PFA FEATURES
PFA is a unique feature of ProtoSounds that is completely controlled by the
operator. You decide how, when or if you want to utilize the feature. By
reviewing following tips you should find solutions or suggestions to the various
operating scenarios you might encounter when using PFA.
Tip #1: You can escape the PFA sequence by interrupting the transformer
throttle before the first PA arrival message plays in Event 2 (neutral before
reverse).
Tip #2: You can terminate PFA at anytime by turning the transformer
throttle off for 15 seconds.
Tip #3: You do not have to be in the forward state to utilize PFA. For
example if you activate the PFA feature while in reverse and interrupt the
throttle to enter neutral, you will be entering neutral before forward rather than
neutral before reverse as defined in Event 2 above. Consequently, the forward
phase will be rendered inactive by ProtoSounds instead of the reverse state as
explained in Event 3. This will allow your train to leave the train station in the
same reverse direction that it arrived in.
Tip #4: You can utilize PFA even if you are double-heading with another
engine, regardless of whether it is equipped with ProtoSounds or PFA. If the
engine isn’t equipped with PFA, the only thing to remember is that you not turn
up the transformer throttle very high when entering the reverse state found in
Event 3. If the throttle is set too high, then the second locomotive will begin
vibrating on the track as its motors will be turning in the reverse state since
engines not equipped with PFA cannot disable the reverse state and will thus
continue powering their own motors. If your second engine is equipped with
PFA, it can be disabled by entering RESET function 28. See the section on
programming RESET functions on page 18 of this manual to disable PFA.
Tip #5: It is not necessary for the squealing brake sounds to be heard to
play the PFA sounds. For example, the brake sounds won’t be heard if the high
voltage setting is below 13 volts and the power is interrupted to enter the
neutral state.
Tip #6: You can leave any of the event states at any time after entering the
state by simply interrupting the transformer throttle. Any sound effects
programmed to play in that event will simply not occur. The only exception is
Event 2 and Event 5. In Event 2, interrupting the throttle has no affect on PFA
until after the PA arrival message has played and the doors have opened. In
Event 5, you cannot interrupt PFA until after the engine begins to move.
Interrupting the throttle before the engine begins to move has no affect on the
locomotive.

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SELF-RECHARGING BATTERY BACKUP
ProtoSounds® state-of-the-art design includes a self-recharging battery
backup system for improved performance at any speed. The battery ensures
that power to the sound system will remain on during directional changes,
setting RESET options or when travelling over dirty track and switches.
The self-recharging battery backup system is automatically turned on or off
whenever track power is turned on or are off. There no switches needed to
enjoy the benefits of the automatic battery backup system.
ProtoSounds® contains a warning alarm if the battery backup system fails
to automatically disengage when track power is turned off. Should the
backup system fail, you will hear a repeating whistle blast indicating this
has occurred. Should this happen, unplug the battery from the ProtoSound
module (to prevent the battery from being run down) and contact MTH for
instructions on returning the tender for repair.
REPLACING THE PROTOSOUND® BATTERY
The ProtoSound® battery (located in the tender body, is a special NiCad
7-cell, 8.4v battery - NOT the 6-cell, 7.2v battery found in most
convenience stores. The 6-cell NiCad is NOT recommended for use with
ProtoSound® applications. The battery is continually charged from the
track when power is applied and should last for up to five years. In
addition, the NiCad battery is a dry battery and should not leak or cause any
damage to your locomotive during its lifetiem.
If you notice that the sounds seem distorted or garbled at low voltages or
become silent when power from the transformer is shut off, the battery may
be going bad. Before replacing the battery, you should put the engine in
NEUTRAL and leave the transformer throttle set at about 12 volts for 15
minutes. This should temporarily recharge the battery. If the garbled or
distorted sounds are reduced, then your battery charge has worn down. You
can give your battery a full charge by leaving the engine ON in the
NEUTRAL position for 18 hours. (Make sure the smoke unit switch is in
the OFF position to prevent harm to the smoke unit wicking).
If you need to replace the battery, replacement ProtoSound® batteries are
available from MTH ProtoSound Electronics at 7020 Columbia Gateway
Drive, Columbia, MD 21046. A standard 9v alkaline battery can be

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MTH Blue Comet Operating Manual
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substituted as a temporary fix, but since alkaline batteries can’t take a
charge, it will eventually wear down. Regardless, it should give you a week
to a couple of months use while you wait for your replacement
ProtoSound® battery to arrive.
PROTOSOUND® VOLUME ADJUSTMENT
Your ProtoSound® system has two types of volume adjustment. A
manual turn knob on the bottom of the chassis (See Fig. 6 below) allows
you to control all the sounds in the system and a remote control “RESET"
option (Option # 6), allows you to control the volume level of the engine
sounds remotely from the transformer. Turning the volume adjustment
knob clockwise will increase the volume and counterclockwise will lower
the volume of all sounds; bell, horn, engine sounds, Cab Chatter, etc. For
information on operating the RESET volume adjustment option, see the
section entitled “Programming ProtoSound RESET Options” on the
following pages.
ProtoSound Manual
Volume Adjustment Knob
Figure 6: Adjusting The ProtoSound® Volume

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USING “RESET" TO PROGRAM
PROTOSOUNDS®
As mentioned earlier, there are several programmable options in each
ProtoSound-equipped engine that can be remotely set from any compatible
standard AC transformer equipped with a whistle button. For a list of
compatible transformers, see the chart on page 34. This hands-off approach
gives you unprecedented control of your railroad empire’s motive power
never before seen in model railroading. Each programmable feature can be
accessed whenever your engine is in the RESET state as described earlier
on page 5. By following the instructions below you will find the
programming easy and straight forward.
ENTERING RESET OPTIONS
ProtoSound® is equipped with a few programmable features that are
accessed in the RESET state by moving the transformer throttle up and
down between full voltage and low voltage (6 to 8 volts) without shutting
the transformer off completely. Each time this is done you advance, one
feature at a time, through the available options. An air-release sound is
heard each time the throttle is advanced. In addition, there are special
sounds to tell you what RESET position you are in.
For example, if you want to select Feature 2, you put the engine in
RESET, and move the throttle up and down from full throttle to low two
times. After the second advance, you will hear two “clinks" indicating that
the computer is now in Feature 2. Advance the throttle again and you will
hear three “clinks" for Feature 3. Advance it two more times and you will
hear a “clank" indicating
that you are now in
Feature 5. Advance the
throttle two more times
and you will hear a
“clank" and two “clinks"
indicating Feature 7. ((5
throttle advancements = 1
clank) + (2 throttle
advancements = 2 clinks)). “Clank + “Clink" + “Clink" = Feature 7. You
can advance the throttle as quickly as you like (though you may not hear the
air-release sounds) and the computer will still remember the number of
Clink, Clink
Clank, Clink
In RESET Mode
Move The Throttle
Up & Down From
High Voltage To Low
2 Times
Advance The Throttle
Up & Down From
High Voltage To Low
4 More Times
Listen For The
2 Clink Sounds
Listen For 1 Clank
And 1 Clink Sounds

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MTH Blue Comet Operating Manual
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times the throttle is advanced by playing back the number of “Clinks" and
“Clanks" to confirm the feature you’ve selected.
SETTING THE ENGINE VOLUME
Of all the sounds that come with each ProtoSound-equipped locomotive,
the one most often turned down is that of the engine volume because it is
the one sound normally heard whenever the engine is running and is what
usually can become tiresome to the ear over prolonged running sessions.
The volume adjustment is controlled through RESET Feature 6.
To access the feature, advance the transformer throttle to put the engine in
RESET. Move the throttle up and down, as described on page 5, 6 times.
After you hear the “clank" and “clink" indicating that you are in Feature 6,
press the whistle button to select the engine volume level you desire.
Pushing the whistle button once will give you full volume, which is the
factory setting. Pushing the whistle button a second time will give you 50%
volume, pushing it a third time will give you 25% volume and pushing it a
fourth time will give you no sound. The microprocessor will immediately
play the sound level each time the whistle button is pushed so that you can
decide if it is acceptable. You can recycle through the four choices by
simply continuing to
press the whistle button.
Once you have decided
on the appropriate
volume level, turn the
transformer throttle off
and on again or press
the transformer direction switch to lock in your selection. The volume
adjustment will remain set at the level you have chosen until you change it
again. Regardless of the engine volume setting, the horn, bell, compressor
and Cab Chatter sounds will function normally. In fact because only the
engine volume is affected by selections in Feature 6, when you select 0
volume, you can still hear the horn, bell and Cab Chatter sounds when the
engine is running or in neutral.
Clank, Clink
In RESET Mode
Move The Throttle
Up & Down From
High Voltage To Low
6 Times
Listen For 1 Clank
And 1 Clink Sounds
Push The Whistle Button
Until You Reach The
Setting You Desire
Interrupt The Throttle
To “Lock-In”
The Volume Setting
H

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PROGRAMMING FOR A SEPARATE BELL BUTTON
CONTROLLER
To operate ProtoSounds with a
separate bell button controller,
like the Lionel® No. 5906 bell
button, you will need to wire up
the controller to your
transformer and track as shown
in Fig. 7. Once the button is
wired, ProtoSounds comes
preprogrammed to allow you to
operate the bell by simply
pushing the bell button once.
To turn the bell off, push the
button again. If the bell doesn’t’t function when you press the button, you
may need to re-program ProtoSounds to operate with a separate bell button
controller. To do this enter RESET and go to Feature 20. (See the section
Using RESET To Program ProtoSounds®on page 18.) Once in Feature
20, press the whistle button and wait for the module to sound a bell ding(s).
Continue pushing the
whistle button until the
module plays back two
dings (signifying that the
module has been
programmed for a bell
button). Simply turn the
throttle off and then on
again to “Lock-In" the new setting. To reset the computer to its original
factory (default) setting (no separate bell button operation), repeat the above
procedure but keep pushing the whistle button until the computer only
responds with one bell ding.
PROGRAMMING FOR SQUEAKING BRAKE
OPERATION
ProtoSounds can be programmed for squeaking brake operation in three
different manners; (1)Squeaking brakes can be activated by bell button
control, (2)they can be programmed for continuous operation subject to
throttle changes or (3)they can be programmed to be turned off. The default
setting is (1) Squeaking brakes are activated by bell button control as
described on page 8. To change the default setting, enter RESET and go to
Common
RED Wire
BLACK Wire
U
A
U
B
U
C
U
D
Figure 7: Wiring Up A Bell Button
Clank, Clank, Clank,
Clank, Clank
In RESET Mode
Move The Throttle
Up & Down From
High Voltage To Low
20 Times
Listen For 5 Clank
And 0 Clink Sounds
Push The Whistle Button
Until You Hear 2 Dings
Interrupt The Throttle
To “Lock-In”
The Volume Setting
H