MTHTrains DL-109 DIESEL ENGINE User manual

R
ELECTRIC TRAINS
MTH DL-109 DIESEL ENGINE
OPERATING INSTRUCTIONS
Thank you for purchasing the MTH Electric Trains DL-109 diesel
locomotive. This ¼” scale reproduction of the famous DL-109 locomotive
measures over 19” in length and weighs over 5 pounds. Despite its scale
size, the locomotive is capable of operating on O-42 3-rail track with any
compatible AC transformer (see the chart on page 31 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 is 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 Basic Operating Instructions
found on Pages 3 and 4 should be read so that you understand the basics of
the operating system.

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DL-109 Operating Manual
Table Of Contents
QUICK START - BASIC OPERATION 3
ProtoSmoke® UNIT OPERATING INSTRUCTIONS 4
Proto-Sound® OPERATINGINSTRUCTIONS 5
DCRU® Reverse Unit Operation(All 3-Rail Models) 5
Horn Operation 6
Bell Operation 6
ProtoCoupler® Operation 7
Squeaking Brake Sounds 8
Tips On Using Squeaking Brakes Sounds 9
Passenger Station Sounds (PFA) 10
Quick Overview On Activating and Triggering PFA 12
Tips On Using The Passenger Station Sounds 15
Reverse Unit Lockout Control Functions 16
Locking The Engine Into Forward or Reverse 16
Unlocking The Engine 16
Self-Charging Battery Backup System 17
Replacing The Battery 17
Proto-Sound® Volume Adjustment 18
USING “RESET" TO PROGRAM Proto-Sound® 19
Remotely Setting The Engine Volume 19
ProgrammingForSqueakingBrake Operation 20
Programming For Horn In Neutral Operation 20
ProgrammingForProto-Coupler® Operation 21
Turning Off Cab Chatter Sounds 21
Programming For PFA Operation 22
Activating Remote Lock-Out Control 22
Resetting All Proto-Sound® Options To Factory Defaults 23
OIL & LUBRICATION INSTRUCTIONS 24
TRACTION TIRE REPLACEMENT INSTRUCTIONS 25
LIGHT BULB REMOVAL & REPLACEMENT 26
TROUBLE SHOOTING PROTO-SOUND®PROBLEMS 27
Proto-Sound® RESET Feature Chart 30
Transformer Wiring Chart 31
O-42 OPERATION 32
SERVICE AND WARRANTY INFORMATION 36
HOW TO GET SERVICE 36
LIMITED ONE YEAR WARRANTY 36
WARNING:
When using electrical products, basic safety precautions should be followed including the
following:
-- Read this and all related manuals (transformer/power supply, locomotive, etc.) thoroughly
before using this device.
-- This device is not recommended for children under 8 years of age without adult supervision.
-- MTH recommends parents examine the toy transformer used to power this device periodically
for conditions that may result in the risk of fire, electric shock, or injury to persons, such as
damage to the primary or output cord, plug blades, housing or other parts (including proper
functioning of the circuit breaker), and that, in an event such conditions exist, the transformer
should not be used until properly repaired.

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DL-109 Operating Manual
QUICK START - BASIC OPERATION
The MTH DL-109 contains state-of-the art electronics with several built-in
automatic features for incredibly realistic operation. Despite these advanced
features, the DL-109 is easy to operate with any compatible standard AC
transformer (see the compatibility chart on page 31). All models are
equipped with an operating smoke system that should be primed with
smoke fluid before operating. Adding 20 - 25 drops of fluid through the
smoke stack should be sufficient. (See Figure 1a). If you choose to not
prime the smoke unit(s) with fluid, turn the smoke unit switch located
under the rear drive truck(s) to the
OFF position. (See Figure 1b).
This will prevent any damage from
occurring to the smoke unit when
the engine is running without a
primed smoke unit. For more
information see the section on Page
4 on smoke unit operation.
The DL-109 locomotive 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. Once the engine is placed on the track, the throttle on the
transformer can be advanced. You will see that only the engine’s lights
come on and that only two dings of the ProtoSound bell occur followed by
the diesel start-up sounds (on ProtoSound equipped 3-rail models). The
engine does not run. This is known as the RESET (see fig 2) state and is
explained in more detail beginning on Page 5. The ProtoSound® DCRU®
will not power the motors until the throttle is turned OFF and then ON
ON OFF
Coupler
Direction
Switch
Smoke Unit
ON/OFF
Switch
Figure 1b: Locating The Smoke Unit &
ProtoCoupler®Selection Switch
RESET
Neutral
Reverse
Neutral
Forward
Figure 2: DCRU™ Cycle Phases
Add Smoke Fluid
Figure 1a: Adding Smoke Fluid to the Smoke Unit

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DL-109 Operating Manual
again. At this point, the engine will now function just like any other
electronic or mechanical E-unit.
PROTOSMOKE™ UNIT OPERATION
The DL-109 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
power truck must be in the ON position in order for the smoke unit to function. See Fig. 1b on
page 3.
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 20 - 25 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. 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 20-25 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 20 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
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 circuit board from the smoke unit body as seen in Fig.3. After removing the circuit
board screws lift the circuit board away and inspect the wick. If the wick is darkly discolored
and hard, it should be replaced.
Smoke Unit
Circuit Board
Mounting Screws
After Removing
Mounting Screws,
Lift Circuit Board
To Reveal Wicking
Figure 3: Inspecting The Smoke Unit Wicking

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DL-109 Operating Manual
Proto-Sound® INSTRUCTIONS
The MTH Proto-Sound® digital sound and train control system provides
the operator with unprecedented realistic operation on your model railroad.
In addition to actual diesel engine, CD-equivalent 16-bit digital sounds,
you get the following features:
1. ∗Built-In DCRU® Reverse Unit * Authentic Diesel Engine Horn Sound *
Authentic Diesel Engine Bell Sound * Squeaking Brake Sound * Passenger
Station Sounds * Operating Remote Controlled ProtoCoupler™ *
Self-Charging Battery Back-Up System With Automatic Battery Shut-Off *
Remotely Controlled Reverse Unit Lock-Out * Remotely Adjustable Diesel
Engine Volume * Authentic Diesel Engine Start Up & Shut Down Sounds *
Each feature is described among the following pages. Though the system
is easy to use, we encourage you to read the instructions thoroughly.
Proto-Sound® DCRU® REVERSE UNIT
As mentioned in the Basic Operating section, the engine is controlled by a
Proto-Sound® 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 Proto-Sound® 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.
Proto-Sound® 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, Proto-Sound® has its own
“Computer" controlling these functions. 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

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DL-109 Operating Manual
advance the transformer throttle past 10 volts when you first 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.
Proto-Sound® comes with several programmable functions, including
Engine Volume Adjustment, Separate Bell Button Operation
(pre-programmed at the factory), Cab Chatter On/Off Control, ProtoCoupler
On/Off Control and Horn-In-Neutral Operation. 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.
HORN OPERATION
Your MTH DL-109 Proto-Sound®-equipped engine is equipped with a
digital recording of a diesel horn. The horn sound can be activated anytime
the engine is in forward or reverse by pressing the horn/whistle button on
your transformer. The horn will continue to blow as long as the
horn/whistle button is depressed. The horn will not function in RESET and
must be configured through a RESET option to allow the horn to work
when the engine is in neutral. See page 20 for information on horn
programming in the Using RESET To Program ProtoSounds®section of
this manual.
BELL OPERATION
Your Proto-Sound® equipped engine also features a digital recording of an
actual steam engine bell. The bell can be turned on or off by simply
pressing the Bell button on your transformer anytime the engine is in
forward, neutral or reverse. The bell will continue to ring until the bell
button is depressed a second time. Note: The bell will not function in
RESET.

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DL-109 Operating Manual
In fact, because of Proto-Sound® 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 MTH DL-109 Proto-Sound®-equipped locomotive has two
coil-wound ProtoCouplers™ for remote uncoupling action. The couplers
are mounted on the power trucks. Because the ProtoCoupler™ is controlled
through a Proto-Sound® 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
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
H H
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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DL-109 Operating Manual
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. 4.
For multiple heading purposes,
only one of the two
Proto-Couplers will function at
any one time. Use the coupler
direction switch as shown in
Fig. 1b on page 3 to select
either the front or rear coupler.
Simply slide the switch toward
the direction of the coupler you
want to make active.
Note: This scale DL-109 contains a three position switch. If the switch is moved to
the front of the engine, the front coupler will be selected. The switch moved to the
center selects the rear coupler. Moving the switch to the rear most location controls
the rear coupler on the separately purchased DL-110
NEUTRAL-ACTIVATED CAB CHATTER SOUNDS
Whenever your diesel locomotive is parked in Neutral, randomly played
“Cab Chatter” sound effects will occur every 2 to 30 seconds. There are a
total of four of these Cab Chatter sequences that capture authentic radio
transmissions between dispatcher and engineer. They are designed to play
at random intervals to eliminate repetitive and boring sequences though
there is no guarantee that you won’t hear the same message repeated two or
more times..
SQUEAKING BRAKE SOUNDS
Proto-Sound® 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 sound
oil coupler
knuckle
Figure 4: Lubricating The ProtoCoupler Knuckle
Throttle Down From
High Voltage To Low Listen For The
Squeaking Brake Sounds

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DL-109 Operating Manual
itself is a stored recording on the Proto-Sound® software chip and will
always play the same brake sound for the same three second length 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 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
Users will find the squeaking brake 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. However, you may find that your engine
continues to play the brake sounds once your engine comes to a
stop, or that the sounds stop 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 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.

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DL-109 Operating Manual
Operating Proto-Sound® Passenger Station
Sound Effects
Passenger Station Announcements (PFA)
Proto-Sound® is equipped with operator controlled Passenger Station
Sounds, referred to as PFA. The PFA sequence is designed to simulate
the arrival, disembarking, embarking and departure of a passenger train
in a Passenger Station. This easy-to-use feature allows you to play
digitally recorded sounds of Passenger Station sounds while your
engine is parked in the Neutral State. No additional wires or
modifications are needed to enjoy these amazing sound effects. The
sounds themselves are randomly “shuffled” by the Proto-Sound®
computer. This gives the system the ability to play the various sounds
in a different order each time PFA is enabled.
Activating Passenger Sounds -Quick Overview-
The following is a quick overview on how you can operate PFA.
The train on track moving Forward or Reverse direction.
B
Press and Hold Bell Button For 3+
Seconds, Listen For a Horn Blast or
Air Release, then Remove your Finger
from the Button.
BPress Bell Button Again Quickly to
Stop Bell Chime.
Your train is now ready for you to play the PFA.

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DL-109 Operating Manual
d
Bell
Horn
Whistle
Direction
OR
To Play PFA, Stop Train Direction.
This Can Be Done by Pressing the
DIRECTION Button or Cycling the
Transformer Handle.
At This Time the Train Will Stop in
Neutral.
In a Few Seconds, An Arrival Message
Plays, Followed by a Background
Noise.
STOP
d
Bell
Horn
Whistle
Direction
OR Change/Press Direction- The Train Will
Remain In Neutral. It Will Continue to
Play More Background Noises.
d
Bell
Horn
Whistle
Direction
OR
Change/Press Direction- The Train Will Remain
In Neutral. You Will Hear a Double Air Release,
Departure Message Plays More Background
Noises.
d
Bell
Horn
Whistle
Direction
OR
GO
Change/Press Direction- The Train Will Remain In
Neutral. You Will Hear Closing Doors, Horn Blast,
a Few Bell Chimes and Train Departs in the
Direction the Train First Stopped.
For more detailed PFA instructions, read the following.

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DL-109 Operating Manual
Activating Passenger Sounds (PFA)-Detailed PFA
Instructions
Arming The Passenger Sounds Feature
Before the Passenger Station sounds can be heard, the feature must be
activated. The feature can be activated in one of two ways.
Option 1: If you are using the Z-4000™ transformer, or any transformer
with a separate bell button controller, you can activate the feature by simply
pressing and holding the bell button for at least three seconds (it does not
matter if you are in forward, neutral or reverse). You will hear the bell turn
on and, after three
seconds, you should
hear a short horn blast
or air release. Once the
horn blast or air release
is heard, the bell button
can be released. The
bell will continue to
chime, so if you want to turn off the bell ringing, simply press and release
the bell button. If you were in neutral, interrupt the transformer throttle to
enter the next directional state (either forward or reverse). (Note: the PFA
will only play in the first Neutral after it is armed. You can not interrupt
the power twice to enter another direction and still have the PFA active.)
You can now trigger the sounds to begin playing when you next enter
Neutral.
Option 2 If you do not have a Z-4000™ transformer or separate bell
button available, you can activate the PFA using your transformer’s whistle
button control. To arm the PFA, turn on the transformer throttle and cycle
your engine into Neutral
(not RESET). Once in
neutral, set the transformer
throttle to 8 volts or less
and press and hold the
whistle button for at least
three seconds. You will
hear the bell turn on and,
after three seconds, you
should hear a short horn blast or air release. Once the horn blast or air
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
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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DL-109 Operating Manual
release is heard, the whistle button can be released. The bell will continue
to chime, so if you want to turn off the bell ringing, simply press and release
the whistle button. Interrupt the transformer throttle to enter the next
directional state (either forward or reverse). (Note: the PFA will only play
in the first Neutral after it is armed. You can not interrupt the power
twice to enter another direction and still have the PFA active.) You can
now trigger the sounds to begin playing when you next enter Neutral.
TRIGGERING PASSENGER STATION
ANNOUNCEMENTS
Once the PFA feature has been activated, it will be played the next time
the engine enters neutral. At this point, Proto-Sound® will take over
control of your engine, disabling the bell and whistle button. In addition,
Proto-Sound® reconfigures the way the reverse unit functions during the
operation of the PFA feature. This forces the engine to leave your
Passenger Station in the same direction as it arrived. The following
operator controlled “Events” control the PFA’s actions and sounds. (Note:
The direction states shown assume the PFA is entered from forward. If
entering the Passenger Station in reverse, the direction states shown will
be reversed.)
Event 1: Interrupt the transformer throttle to cycle the engine from forward
into neutral. If the throttle was at 14 volts or higher, the squeaking brakes
sound will play. Once the engine is stopped, the throttle must be turned on
to keep it in the neutral state. Note: Failure to turn the throttle back on
within 3 seconds of leaving forward will disable PFA and shutdown
Proto-Sound®. The next time power is turned on, the engine will be in
the RESET position. See page 19 for additional information on RESET.
If the bell was not turned off after
arming PFA, it is now turned off
automatically. After entering neutral,
Proto-Sound® will immediately play a
horn blast or an air release sound,
followed approximately 2 seconds later
by an Arrival Announcement.
Following this arrival announcement,
the sounds of doors opening and the conductor saying “Watch your step” is
heard. At this point, various Passenger Station sounds can be heard,
including passenger footsteps, muffled voices, baggage being moved about
Put Engine In Neutral
At Low Power
Listen For Air Release Sound
And PA Arrival Message
EVENT 1

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DL-109 Operating Manual
and whistling for a taxi. Additionally, several conductor highlights will be
heard in the foreground.
Event 2: Interrupt the transformer throttle
again to cycle the engine from neutral into
reverse. In order to have the engine leave
the yard in the same direction it entered
Proto-Sound® disables the motors in this
reverse state to prevent the engine from
running backwards. PFA confirms reverse is
entered by playing the conductor saying
“Baggage to the right/left.” Once this
highlight is played, the Passenger Station sounds heard in Event 1 will
continue to play.
Event 3: Interrupt the transformer throttle
again to cycle the engine from reverse back
to neutral. PFA confirms that the engine is
now in neutral by sounding two quick air
releases. This is followed approximately two
seconds later by a Boarding Announcement
message and continued Passenger Station
sounds. Conductor highlights, such as
“Welcome aboard” and “Tickets please” will play randomly.
Event 4:Interrupt the transformer throttle again to complete the PFA
feature and cycle the engine into forward. PFA confirms it has entered
forward by playing the conductor’s call “All Aboard!” and the sound of the
passenger car door closing. Within two seconds, the whistle will sound two
short blasts (three if entering reverse), and
the bell will begin to chime. After a few
chimes of the bell, the engine will begin
moving in forward with the bell continuing
to ring. A few seconds later, the bell will
turn off, and the engine will resume normal
operation. Note: When entering Event 4,
it is important to set the transformer
throttle at a high enough setting that the
engine will begin to move when the
motors are activated. However, the throttle should not be too high for the
engine to maintain a safe operating speed.
Listen For 2
Air Release Sounds
Interrupt Throttle To
Enter The Next Phase
EVENT 2
Listen For The
Conductor To Say ...
Interrupt Throttle To
Enter The Next Phase
EVENT 3
Listen For Conductor
To Say ...
Interrupt Throttle To
Enter The Next Phase
EVENT 4

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DL-109 Operating Manual
TIPS ON USING THE PFA FEATURES
PFA is a unique feature of Proto-Sound® that is completely controlled by the
operator. You decide how, when or if you want to utilize the feature. By
reviewing the 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 man’s whistle plays in Event 1 (neutral).
Tip#2: You can exit PFA at anytime by turning the transformer throttle Off for
15 seconds.
Tip#3: You do not have to be in Forward to utilize PFA. For example, if you
activate the PFA feature while in Reverse, your train will leave the station/yard
in the same reverse direction that it arrived in.
Tip#4: You can use PFA even if you are double-heading with another engine
regardless of whether the second engine is equipped with an PFA programmed
Proto-Sound® module. If the second engine isn’t equipped with PFA, the only
thing to remember is that you not to turn up the transformer throttle very high
when entering Reverse in Event 2. If the throttle is set too high, then the second
locomotive will begin vibrating on the track as its motors will be turning in
reverse. If your second engine is equipped with PFA, you may want to disable
the PFA when used in double-headed operations. To disable PFA, see the
section on programming RESET functions on page 26 of this manual.
Tip#5: You can leave any of the event stages at any time by simply
interrupting the transformer throttle. Any sound effects programmed to play in
that event will simply not occur. The only exceptions are Event 1 and Event 4.
In Event 1, interrupting the throttle has no effect on PFA until after the man’s
whistle has completed and the freight car doors have opened. In Event 4, you
cannot interrupt PFA until after the engine begins to move. Interrupting the
throttle before the engine begins to move has no effect on the locomotive’s
operation.

16
DL-109 Operating Manual
Special Reverse Unit Options
Reverse Unit Lockout Operation
For operators who wish to lock their engine into a single direction,
Proto-Sound® unique design eliminates the need for a lock-out switch on
the locomotive. This will allow users to run the engine on layouts
equipped with block signals or stop stations that would normally cycle the
engine back into neutral. Note: The feature must be first turned on by
accessing RESET Feature 40 (See page 22).
Locking the Engine into Single Direction Operation
Cycle the transformer throttle so that your engine is operating in the
direction you wish to lock it in (forward, neutral or reverse). With the
throttle set to approximately 8 volts, press and hold the horn/whistle
button. While holding the horn/whistle button, turn the throttle OFF, and
then release the horn/whistle button. After 2 seconds, you will hear a short
horn blast. IMMEDIATELY turn the throttle back on. The engine is now
locked, and will continue in the previous direction whenever power is
applied to the track.
Unlocking The Engine
With the throttle set to approximately 8 volts, press and hold the
horn/whistle button. While holding the horn/whistle button, turn the
throttle OFF, and then release the horn/whistle button. After three
seconds, a single bell will be heard indicating that the engine is unlocked.
When power is again applied, the engine will enter RESET and perform as
normal.
NOTE: When locking the engine in the Forward or Reverse positions,
the horn/whistle button will blow the horn/whistle. But when locking the
engine into the NEUTRAL position, the horn/whistle button may turn on
or off sounds of the bell. Remember, the horn/whistle doesn’t blow in
NEUTRAL (unless you programmed it to do so using Reset Feature 25 -
see page 20 for details), only the bell rings.

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DL-109 Operating Manual
SELF-CHARGING BATTERY BACKUP
Proto-Sound® includes a self-charging battery backup system for improved
performance at any speed. The battery ensures that power to the sound
system will remain on during directional changes, while setting RESET
options or when traveling over spots of dirty track and switches. The
self-charging battery backup system is automatically turned on or off.
There no switches needed to enjoy the benefits of the automatic battery
backup system.
Proto-Sound® 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 that
this has occurred. Should this happen, unplug the battery from the
Proto-Sound® module (to prevent the battery from being run down) and
contact MTH for instructions on returning the train for repair..
REPLACING THE PROTO-SOUND® BATTERY
The Proto-Sound® battery 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 Proto-Sound® applications. The battery is
continually charged from the track when power is applied above 10 volts
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 lifetime.
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 and the transformer throttle set at about 12 volts for 6
hours.
Note: When charging the battery in neutral, if your trains contains a
Smoke Unit should be turned OFF to prevent damage to the wick and the
heating elements.

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DL-109 Operating Manual
MANUALLY ADJUSTING THE PROTO-SOUND®
VOLUME
Your Proto-Sound® system has two types of volume adjustment. A manual
turn knob on the bottom of the chassis (See Fig. 5 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 one
direction will increase the volume. Turning it the opposite directions 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 Proto-Sound® RESET Options” on the
following pages
Volume
Adjustment
Knob
Figure 5: Adjusting The Proto-Sound® Volume

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DL-109 Operating Manual
USING “RESET" TO PROGRAM
PROTO-SOUND®
Proto-Sound® is equipped with several programmable features which are
accessed in the RESET state by moving the transformer throttle up and
down between full voltage and low voltage (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 and returned. In addition, there are
special sounds to tell you
what RESET position you
are in.
For example, if you want
to select Feature 2, 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 times the throttle is advanced by playing back the number of
“Clinks" and “Clanks" to confirm the feature you’ve selected.
Remotely Adjusting The Engine Volume - Reset Feature 6-(1
Clank, 1 Clink)
Reset 6 allows you to change the volume setting of the motor sounds
without effecting the volume of other sounds, such as the horn, bell, cab
chatter, etc. To use, cycle to Reset Feature 6 and press the Horn/Whistle
button. A single bell
will play, and the chuff
will begin at the current
volume. Each time the
Horn/Whistle button is
pressed, a bell will
soundandthevolume
setting will cycle down
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
In RESET Mode
Move The Throttle
Up & Down From
HighVoltageToLow
6 Times
Listen For 1 Clank
And 1 Clink Sounds
Push The Horn/Whistle Button
Until You Reach The
Setting You Desire
Interrupt The Throttle
To“Lock-In”
The Volume Setting
H

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DL-109 Operating Manual
to the next level. The levels available are 100%, 50%, 25%, and 0%. After
0%, pressing the horn/whistle button again will return the motor sounds to
100%. When the desired level is reached, lock the changes by interrupting
the throttle and cycling the engine into forward.
Programming For Squeaking Brake Operation- Reset Feature
45 (9 Clanks, 0 Clinks)
Reset Feature 45 allows you to determine if and how the Squeaking Brakes
recording will be activated. To use, cycle to Reset Feature 45 and press the
Horn/Whistle button. The engine will play a series of bells. This indicates
the current setting. Each time the Horn/Whistle button is pressed,
Proto-Sound® will cycle to the next available setting and provide the
appropriate bell indicator. The settings for Reset Feature 45 are 1 Bell = On
Demand (Enabled when PFA is activated), 2 Bells = Always On, 3 Bells =
Off. When the desired setting is reached, lock the changes by interrupting
the throttle and cycling
the engine into forward.
Programming For
Horn In Neutral
Operation- Reset
Feature 25 (5 Clanks)
Reset Feature 25 allows
you to operate the Horn while the engine is in the Neutral state. When ON,
pressing the Horn/Whistle button while in Neutral, with 10V AC or less on
the track, will cause the Horn recording to sound. To use, cycle to Reset 25
and press the Horn/Whistle button. The engine will play a series of bells.
This indicates the current setting. Each time the Horn/Whistle button is
pressed, Proto-Sound® will cycle to the next available setting and provide
the appropriate bell indicator. The settings for Reset 25 are 1 Bell = OFF, 2
Bells = ON. When the
desired setting is reached, lock
the changes by interrupting
the throttle and cycling the
engine into forward.
In RESET Mode
Move The Throttle
Up & Down From
High Voltage To Low
45 Times
Listen For 9 Clank
And 0 Clink Sounds
PushThe Horn/Whistle Button
Until You Hear The
Appropriate # Of Dings
Interrupt The Throttle
To “Lock-In”
The Brake Setting
H
In RESET Mode
MoveTheThrottle
Up & Down From
High Voltage To Low
25 Times
Listen For 5 Clank
And 0 Clink Sounds
Push The Horn/Whistle Button
Until You Hear
2 Bell Dings
Interrupt The Throttle
To “Lock-In”
The Horn Setting
H