SoundTraxx DSD-150DSX Owners Manual

ALL ABOARD!

Congratulations on the purchase of your SoundTraxx™ Digital Sound Decoder ™(DSD). Properly installed, the DSD
will provide all the pleasures of high quality, digital onboard sound and the benefits of today’s DCC (Digital Command
Control) technology .

With the proper tools, basic modeling skills and common sense, equipping a locomotiv e with sound is not difficult. It
may, however, be a new experience for you, and you will find that successive installations will go more quickly than
the first. The Digital Sound Decoders have some unique features and capabilities that require some steps not found
in regular decoder installations. We strongly encour age even the most skilled and experienced modeler to read this
manual thoroughly as it contains instructions and information designed to provide optimum, trouble free perf ormance
from your DSD. We urge you to test the decoder first using the simple test procedure in Appendix B to verify that
ev erything is working as it should. If you do not feel comfortable attempting the installation - don’t! You may prefer to
have your dealer perform the installation while you watch, until you gain some experience.

Please note that while each decoder is tested thoroughly before it is shipped, we cannot control the correctness or
quality of the installation. It is imperativ e that y ou follo w the directions and do not install the decoder bef ore you ha v e
tested it. Never remove the protective heat shrink from the decoder; there are no adjustments or user serviceable
parts and this will void your warranty. Do not shorten any of the decoder wires until you have verified that it is
functioning properly using the Decoder Test.

This manual is divided into two parts for your convenience. Part I is the Owner's Manual, which covers the features
of the Digital Sound Decoder, it's installation and it's operation. Part II is the Decoder Technical Reference. This is
designed for the adv anced user who wishes to have the technical data on the Digital Sound Decoder as a reference
for advanced programming techniques. If this is your first decoder installation, Part I will provide you with all the
information you need to get started.

Digital Sound Decoder Owner's Manual

1

DSD FEATURES AND SPECIFICATIONS

The Digital Sound Decoder is designed to be installed onboard a locomotive in conjunction with a miniature speaker
to provide the ultimate in realism and control. The DSD integrates a full f eatured digital sound system, a Hyperlight™
and a DCC decoder into a single miniature electronic module. The modeler is thus freed of the expense and frustra­tion of trying to fit multiple pieces of equipment into an often space limited locomotive. The Digital Sound Decoder is
compatible with the latest NMRA DCC Standards and Recommended Practices.

The DSD is availab le with prototype-specific sound and lighting effects f or a multitude of North American and foreign
locomotives. Depending on the effect, the sounds are generated continuously, automatically in response to some
other action, or as controlled by the user. Additionally, cer tain sounds can be modified using specific Configuration
Variables (CVs).

Decoder Features

Compatible with the latest NMRA DCC Standards and Recommended Practices as defined by S-9.1, S-9.2, RP-

9.1.1, RP-9.2.1, RP-9.2.2, RP-9.2.3 and RP-9.2.4.
Supports 7 bit address modes for compatibility with ‘simple’ systems.
Supports 14 bit address modes for addressing any locomotive number up to 9,999.
Supports 7 bit consist addressing.
Supports Function Mapping.
Supports paged, register, and direct mode CV programming.
Supports ‘Operation Mode Programming’, allowing man y CVs to be changed on the mainline without using a special
programming track.

Steam Sound Features

The Steam DSD provides high quality digital sounds specific to its prototype. Each Steam DSD includes:

■

Steam Exhaust Chuff

■

Bell

■

Dynamo

■

Cylinder Blowdown (Hiss)

■

Fireman Fred

■

Adjustable V olume Control

■

Auto-Exhaust™ allows chuff to be
synchronized using an exhaust cam cutoff and timbre as locomotive load changes.
sensor or track voltage.

■

Whistle

■

Firebox Blower

■

Airpump

■

Boiler Pop Valve

■

Coupler Clank

■

1 Watt Audio Amplifier

■

Dynamic Digital Exhaust ™modifies exhaust volume,

Throttle Features

■

Supports 14, 28 and 128 speed step modes.

■

Programmable acceleration, deceleration and starting voltage, for prototypical starting and stopping.

■

Use of standard and alternate speed tables; 14 built-in speed tables and 1 user programmable speed table.

■

Thermal and overload protection.

■

DSD-050 suitable for engines whose current dr aw (stalled) does not exceed 1/2 amp (3/4 amp peak). DSD-150
suitable for engines whose current draw (stalled) does not exceed 1-1/2 amp.

Lighting Features

Each DSD also comes equipped with four auxiliary function outputs that can be programmed to accommodate a
number of lighting features including four programmable Hyperlight effects:

■

Simple On/Off Lamp

■

Firebox Flicker

■

Mars Light

■

Intelligent Firebox Flicker - synchronizes with sound of firebox
door opening and closing.

■

Supports “Rule 17” headlight and backup light operation or automatic direction control.

■

100mA current sink capability.

2

Digital Sound Decoder Owner's Manual

IMPORTANT STEPS FOR A SUCCESSFUL INSTALLATION

It will be a great temptation to begin connecting wires immediately. Before you install your DSD, there are some
simple precautions you should take.

First, finish reading this Owner’s Manual!

The DSDs should be handled carefully in a static-free environment. T o discharge static electricity, touch a grounded
water pipe or bare sheet metal surface before handling the DSD.

Work in a clean, well lit area on a nonconductive surf ace . Metal scraps and dirt can get onto the DSD's circuitry and
cause shorts.

Never, ever remove the decoder’s protective shrink tubing. First, it will void your warranty and secondly, you will
compromise part of the decoder’s built-in thermal management system.

Nev er , e v er make connections to the decoder while it is pow ered. Doing so mak es f or an accident waiting to happen.
Make sure all electrical connections are insulated. Avoid using electrical tape if possible as it tends to unravel over

time. We recommend using heat shrinkable tubing instead.
Nev er , e ver allo w the decoder leads to come in contact with any DCC trac k wiring except those specifically designed

for that purpose.
Never allow speaker outputs to become shorted together.
Never allow the motor outputs to become shorted together.
Do not exceed the output ratings for which the decoder is designed.
Take your time and have fun!

DSD Functional Testing

Although each DSD has been fully tested prior to shipment and is ready for installation, we urge you to test your
decoder before installing in your locomotive! W e ha v e developed a simple procedure (see Appenidx B)that assures
you that the DSD is functioning as it should before you do the installation. If this is your first sound or decoder
installation, it will give you an added boost of confidence, knowing that as long as you follow the installation
instructions...it

In the event you do have a problem, please contact your dealer or Throttle Up! for technical assistance first. We will
gladly refund payment or replace any decoder that does not pass the functional test free of charge provided that
none of the decoder wires have been cut short.

Before you get started, we must reiterate ­decoder is functioning properly.

will

work!

do not shorten any decoder leads

Do not install any decoder that does not pass the Functional Test.

until you have verified that the

Digital Sound Decoder Owner's Manual

3

INSTALLATION

10 Easy Steps to Steam Sound

Installing the DSD generally requires the following steps:

1. Select the Locomotive

Choose a locomotive appropriate to the decoder and your installation skills.

2. Plan the Installation

Determine the location of the DSD, speaker, cam, lamps and connectors.

3. Isolate the Motor

Disassemble the locomotive and disconnect all wires to the motor and lights.

4. Fit the Speaker

Trim the speaker frame and/or add baffles to get a sound-tight fit.

5. Modify the Tender Body and Floor

Modify the tender to accept the speaker and decoder.

6. Install the Lamps

Modify headlight castings to accept miniature lamps.

7. Install the Exhaust Cam

Install sycnronizer disk and mount cam switch.

8. Install and Wire the Decoder

Mount the decoder and connect the lamps, motor, speaker, etc.

9. Test the Installation

10. Program the CVs

Program CVs to tune performance and sound effects.

Tools and Materials You Will Need

In addition to the common hand tools found on most modeler’s workbenches, you should have at your disposal:

Low wattage (under 25 watts!) soldering iron
Rosin Core Solder
X-acto knife
Miniature screwdriver set
Diagonal cutters
High speed motor tool (such as a Dremel)
Ohmmeter
Double sided tape

Silicone RTV
We also recommend the following items to ease your installation:
Micro-connectors to facilitate easy separation of items like speakers from the locomotive. Throttle Up! sells P.N.

810012 2-pin microconnector, P.N. 810063 3-pin microconnector, P.N. 810064 6-pin microconnector , P.N. 810065 8­pin microconnector and P.N. 810058, 10-pack of micro-mini connector pins.

We recommend you use insulative and shrink tubing, to insulate your connections. Throttle Up! sells P.N. 810037,

4

Digital Sound Decoder Owner's Manual

which contains an assortment of heat shrink tubing suitable for this purpose and P.N. 810036 which pro vides a length

810053
810054
810055
810056
810057

N-Scale

HO-Scale

S-Scale

O-Scale

G-Scale

SUITABLE

SCALES

SPEAKER SIZEP.N.

● ●

● ●

● ● ●

● ●

● ●

3/4" Speaker
1" Speaker
1-1/2" Speaker
2" Speaker
3" Speaker

of Teflon tubing. Electrical tape will unravel with time and is not recommended!

If you intend to take advantage of the special lighting effects and wish to use 1.5 Volt

microbulbs for this purpose, Throttle Up! offers two sizes; P.N. 810022 has a diameter

of 1.3mm. P.N. 810024 has a diameter of

2.5mm for use in larger scales. You can also

buy these lamps in economical six packs . See

Appendix A.

Throttle Up! also offers a variety of 8 ohm

speakers suitable for use with the DSD.

Choose the largest speaker that can be fit in

the locomotive. The larger the siz e, the better

the sound quality and volume. See Appendix

A for ordering information.

Step 1. Select your Locomotive

If this is the first time you hav e installed sound

in a locomotive, then we suggest y ou choose your locomotive carefully. A f ew simple precautions will ensure that y our

first effort produces a great sounding locomotive instead of an intimidating ball of wires:

-

Do

pick a smooth running locomotive that runs well on straight DC power. A smooth running mechanism is
vital for good throttle control and enhances the realism of the sound. Dirty, w orn out or binding mechanisms
not only overload the decoder , b ut will ha v e trouble starting smoothly and will destroy the illusion created by
the Auto-Exhaust feature if they barely lurch along at half throttle.

-

Do

pick a locomotive with a reasonab ly large, rectangular tender. The larger the tender, the more room you
will have f or installation of the decoder and speak er . It will also allow you to use a larger speaker , giving both
better volume and sound fidelity. Reserve that fa vo rite little shay f or a future installation when you hav e some
experience behind you.

-

Do

start with an engine that is ‘sound-ready’ if possible, such as an engine with predrilled speaker holes , f or
example. The simpler you can make your first installation, the better.

-

Don’t

pick a noisy engine, or one which experiences some arcing or sparking when in operation. The best
sound will come from locomotives powered with can motors. Older, open-frame motors may produce an
offensive, interference sound.

-

Don’t

pick a locomotive whose stall current dra w e xceeds the r ating of the decoder. The f o llowing procedure

can be used to determine a locomotive’s stall current:

1. Place the locomotive on a section of track powered with a conventional DC power pack set to 12
volts for N, HO, S, and O scales or 16 volts for G scale.

2. Connect a DC ammeter in series with one of the track feeders as shown in Figure 1. If your power
pack has built-in meters, they may be used for this purpose.

3. While grasping the locomotive to prevent it from taking off, turn the power pack to full on.

4. Stop the motor from turning by firmly pushing the locomotive down into the track or gr abbing hold of

Digital Sound Decoder Owner's Manual

the flywheel or driveshaft.

5. To ensure the most accurate current measurement, be sure that the power pack voltage remains at
12 volts (16 volts for G scale) during this test.

6. Measure the current the locomotive is drawing while the motor is stalled. This is the stall current and
must be less that the decoder’s rated capacity.

5

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;

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Ammeter

(

)

DC Power Pack

set to 12V

16V for G-Scale

Figure 1 - Stall Current Test Setup

Step 2. Plan the Installation

You should give some thought to where the installation of the various DSD components will be within the locomotive
before you get started. Figure 2 shows a typical installation.

Speaker

Headlight

Blue
White

Purple

Synchronizer
Disk

Motor (+) Lead

Motor (-) Lead

Exhaust Cam

Right Rail Pickup
usually connects

Orange Purple
Gray
Red

Digital
Sound

Decoder

to locomotive frame

Figure 2 - Typical Sound Installation

The decision most critical to the success of your installation will be where to put the speaker. Obviously, the ‘where’
of speaker installation will depend on the size and type of the locomotive. But when considering the speaker’s
location, remember that the volume of the speaker will be greatly enhanced when the speaker is fitted into a small
airtight enclosure with the front of the speaker open to surrounding air. The reason for this is simple: in order to
generate any appreciable sound, the speak er m ust de v elop air pressure . Without an enclosure , any pressure devel-

Backup Light

Blue

Yellow

Black

Left Rail Pickup
usually connects
to tender frame

6

Digital Sound Decoder Owner's Manual

oped by the front of the speaker is canceled b y an opposite pressure behind the speak er . The enclosure isolates the
front and back surfaces of the speaker, thereby increasing the sound pressure and hence, the volume.

Additionally , the enclosure must be sized proportionally to the speaker such that the volume of air enclosed is se v eral
times larger than the speaker diameter. If an enclosure is too small, it will interfere with the speaker operation and
although it cannot be made too large, there is a point of diminishing return. As a rule of thumb , for small speak ers, the
minimum for the length, width and height should be equal to the speak er diameter . Thus the smallest enclosure for a
1" speaker would be 1" X 1" X 1", while 2" X 2" X 2" would be the smallest size enclosure for a 2" speaker . As this is
only a general guideline, exceptions can and must be made in many circumstances.

HOWEVER, the use of a proper speaker enclosure cannot be over emphasized and failure to use one
is almost always the cause for poor sound quality.

Fortunately, most steam engines have a tender and with a little work, the tender itself becomes a great speaker
enclosure. The speaker can face up through the coal bunker or down through the floor. Either way will produce
equally good sound.

You will also want to use the largest speaker possible to get the best bass response. Larger diameter speakers can
be trimmed down in width so they will fit within the tender shell. By building an internal baffle, they can also be
mounted at an angle although this will compromise the available space for the DSD module in all but the largest of
tenders.

In small tenders, the speaker should be mounted f orward in the coal bunk er area, where higher walls are a vailab le to
cover the speaker magnet.

For other locomotives, the speaker enclosure need not be fancy and can be fabricated from sheet styrene, bass
wood, and even cardboard in a pinch! A 35mm film canister usually produces excellent results, as does the card­board tube center of a roll of paper towels.

The Digital Sound Decoder is best suited for installation in the tender, although it will fit in the boiler of larger
locomotives. Boiler installation has the adv antage of requiring considerably less wires that hav e to be routed between
the engine and tender. It will usually come at the expense of some boiler weight and possible reduction in traction.

It is normal for the DSD to get warm after periods of extended operation and its built-in thermal overload protection
will automatically shut down the throttle and audio amplifier if it gets too warm. Therefore, it is important to install the
DSD in a location where it can dissipate the most heat. Avoid placing the DSD near heat sources such as the motor
or lights.

You will also need to decide how you will synchronize the exhaust chuff. The DSD provides two means for synchro­nization. The first method is to use the mechanical cam which works by opening and closing a s witch contact with the
locomotive wheels or axle.

The exhaust cam switch is best mounted so it contacts the inside face of a driver wheel. This will give the most
precise synchronization and ev en produce a wheel slip eff ect if the locomotiv e is accelerated too quic kly! In a pinch,
the exhaust cam can be used with a tender axle, although the synchronization effect will not be exact unless the
tender wheel diameter is an exact multiple of the locomotive driver diameter.

The other method of exhaust synchronization is the DSD’s Auto-Exhaust feature which produces chuffs in proportion
to the throttle setting. This method is recommended for those locomotives where a mechanical cam would be difficult
to install such as N scale and smaller HO locomotives. When used in conjunction with the programmable speed
curves, it is difficult to tell the difference between the Auto Exhaust and the exhaust cam at all but the slowest
speeds.

Next, you will need to consider which lighting effects you will use. The DSD provides four auxiliary function outputs
which can be used for controlling miniature lamps or LEDs. Two of the outputs will usually be used for the headlight

Digital Sound Decoder Owner's Manual

7

and backup light. These outputs ma y be configured f or automatic direction control such that the headlight is on when
the locomotive is traveling in the forward direction and the backup light is on when the locomotive is reversed. The
lights may also be setup for “Rule 17” operation where the engineer must manually turn each light on or off as
appropriate.

The other two outputs are programmable Hyperlight effects and may be used in a variety of ways:

• As a conventional on/off output, they may drive additional bulbs f or the cab light, mark er lights, number
boards, small relays or other electronic circuits.

• As a Mars light, they may be used to sim ulate the famous warning beacon found in front of the modern
steam engines used by railroads such as the Southern Pacific, Union Pacific and Nickel Plate Roads.

• The outputs can also be set up to simulate the flickering glow from the firebox. This is best done by
mounting an orange or red lamp underneath the locomotive’s firebox area.

• A second version of the firebox flic k er eff ect is av ailab le that turns on only when the sound of the firebox
door opening has been activated and turns off when the doors “close”. The lamp for this effect is best
mounted in the cab behind a partially open firebox door detail.

Each Hyperlight output can be independently programmed so it is possible to use one bulb as a Mars light and the
other bulb for the firebox.

The function outputs may also be used to control other electrical devices such as a smoke generator although you
must be careful that such devices do not e xceed the output’s current rating (100 mA) in which case you will need to
add a relay or other low current switching device. A clamping diode may be required for inductive loads, such as a
relay coil.

You must also be careful that the combined current draw of each lamp and the locomotive’s stall current does not
exceed the decoder’s current rating.

Finally, you will need to decide whether or not to hardwire the electrical connections between the tender and the
locomotive or use a pluggable connector. Using a connector will allow you to separate the engine and tender for
storage as well as make painting and service easier but can be unsightly in smaller models and also opens the
possibility of accidentally damaging the decoder by reversing the connector during reassembly. Hardwiring the de­coder will prevent this possibility at the expense of making tender separation difficult.

Throttle Up! offers se veral microconnectors suitab le for locomotive use . P.N. 810064, 6-pin connector and P.N. 810065,
8-pin connectors are best for HO and larger models and they can be wired so they are “damage proof”, i.e., no
decoder damage will occur if they are accidentally plugged together backw ards (see page 14, Step 8). The particular
connector you will use will depend upon the number of lighting functions you are using. The 8-pin connector provides
enough pins to wire the headlight and two auxiliary lighting functions. The 6-pin connector provides enough pins to
wire only the headlight. Individual connector pins are also available which will allow you to disguise the connecting
wires as air and water lines but requires great care when reconnecting them so as not to miswire the decoder.

After you have fully read the installation manual, we suggest reviewing Step 8 on wiring the decoder and draw
yourself a schematic similar to Figure 8 showing all connections between the DSD and various sub-components.
This will also help you determine which connector is best suited for your needs.

Step 3. Isolate the Motor

Pay careful attention this step as it is the most impor tant step in successfully converting any locomotive over

to DCC operation.
The two motor brush connections must be electrically isolated so they are driven exclusively by the DSD motor
outputs. We’re not kidding about this!

8

Digital Sound Decoder Owner's Manual

STOP

Failure to properly isolate the motor will damage your decoder and turn it into an effective, but short
lived smoke generator!

Our warranty specifically excludes damage caused by improperly isolating the motor ; however, in the event you do
damage your decoder , simply return it to Throttle Up! along with the service fee (please call for current amount) and
we will repair and return it promptly.

Begin motor isolation by removing the boiler and tender shell from the locomotive and tender frame.
Before you proceed further , it is important to carefully examine the locomotive wiring and determine where each wire

goes and what it does. The manufacturer’s assembly drawings may be useful here or you may elect to create your
own wiring diagram. In particular , you will need to identify the connections to the left and right po wer pic kups as well
as the (+) and (-) motor connections. Note: f or N, HO, S and O scale locos, the positive motor connection is the one
connected to the right rail (engineer side) power pickup . On G scale locos, the positiv e motor lead is connected to the
left rail pickup (fireman side).

Disconnect all wires leading to both motor terminals. Note that some motor brush connections are made using a
spring contact to the chassis. In such cases , it will be necessary to remove or modify the spring contact as well. Be
aware that some locomotives may make contact between the motor and frame only when the body is reinstalled.

Next, verify that each motor ter minal is electrically isolated from the left and right rail pickups using an volt­ohmmeter or continuity tester . With y our meter set to the ohms scale, touch both meter probes together and note that
the meter indicates 0 ohms (short circuit). Y ou don ’t want to see this indication again! Touch one of the probes to one
of the motor brush terminals. Touch the other probe to the locomotive frame, then the left rail po wer pic kup wire, and
finally to the right rail power pickup wire . Move the first probe to the other motor brush terminal and repeat the tests.
If all tests indicate an open circuit, the motor is properly isolated. Do not proceed further until this is done.

You will also need to disconnect the wires leading to any lights you wish to use. If you plan to use the Full-Wave
method of lamp wiring (see page 15), you must disconnect and isolate both lamp wires. Using an ohmmeter, check
that each lamp lead is electrically isolated from the frame as well as the left and right rail pickups.

If you choose to use the Half-Wave method of lamp wiring (see page 15), leave one lamp lead connected to the
locomotive frame or tender chassis provided the frame or chassis is electrically connected to the proper power
pickup. This will allow you to use e xisting lamp sockets if your engine is so equipped. See Step 8, page 15 "Lighting
Outputs" for specific details.

Step 4. Fit the Speaker

If the speaker is wider than the tender, it will be necessary to
reduce the speaker width to get a proper fit. Determine how
much the speaker must be cut down and remove half of that
amount from each side of the speaker.

Speakers with plastic frames may be trimmed down using a
sharp flat file. File down the speaker sides - work slowly and
alternate from side to side until the speaker just fits within the
tender shell. Be careful to remove only the speaker frame and
outer edge of the diaphragm. Avoid cutting into the diaphragm
itself.

Cut equal amounts

Speakers with metal frames can generally ha ve a larger amount
of frame and speaker cone removed and still maintain a satis­factory sound. On the back of the speaker frame, draw a line
where the first cut will be made. Draw a second, parallel line

from each side.

Figure 3 - Modifying the Speaker

Digital Sound Decoder Owner's Manual

9

marking the other cut. Be sure that neither line cuts into the speaker coil wire.
A Dremel or similar motor tool with an abrasive cutoff wheel will make the job of cutting the speaker go quickly. Be

sure to wear your saf ety glasses! Hold the speaker f ace down and mak e shallow cuts along each line until the frame
has been cut through. Trim the speaker cone with a sharp single edged razor blade or hobby knife.

Check the speaker’s fit into the installation site and trim the speaker frame and cone as needed until the desired fit
is attained. For best performance, the speaker should fit snugly within the tender so that the edges of the speaker
cone are as close to the tender sides as possible without actually touching. Do not allo w the speaker cone to rub the
tender walls as this will produce a “scratchy” sound. Like wise, a large air gap will reduce the speaker’s bass response
but can be filled in with cardstock if needed.

Step 5. Modify the Tender Body and Floor

Depending upon your choice of tender , y ou will probably be mounting the speak er facing do wn on the tender floor or
facing up in the coal bunk er . In either case, a certain amount of “body work” is usually necessary to accommodate the
speaker and decoder. This may include removing weights, mounting brackets, internal bracing and other structural
features.

You will probably need to cut an opening in the tender shell or floor for the speaker. A series of small holes can be
easily drilled and will work as well as one large hole provided the open area is at least one half the area of the
speaker cone. In either case, there should be no openings outside or larger than the speaker cone itself.

Tender Body Modifications

On tenders with low side walls, the speaker is often best mounted facing up in the coal bunker so as to provide
adequate clearance for the decoder which will be mounted against the tender floor. In some cases, it may even be
necessary to add a wooden “retaining wall” to build up height.

Figure 4 - Tender Shell Modifications

Optional wooden
retaining boards to
build up height.

should be slightly smaller

Opening in deck

than speaker diameter

Remove inside walls
and slope sheet if needed.

Styrene

in sub-deck

Cut hole diameter
to slightly less than
speaker diameter.

Perforate coal load
with #55 drill.

Cross section of plastic tender

with molded coal load.

The simplest tenders have a flat dec k across the coal b unk er and are the easiest to deal with. Simply mark or scribe

10

Digital Sound Decoder Owner's Manual

the speaker outline onto the tender deck and using a je weler’s saw, cut out a circular opening about 1/16" inside the
outline marks. Remove all sharp edges and burrs. The speaker is then disguised by covering the opening with a
acoustically transparent coal load. The coal load can be fabricated by contouring a piece of fine screen mesh or
polyurethane foam to represent a coal load and then cov ering it with a thin layer of scale coal cemented in place with
a thin wash of diluted white glue.

Plastic tenders often have a molded coal load already in place . Unfortunately, the inside surface of such tenders are
contoured to match the coal load and do not provide a flat mounting surface for the speaker. In such cases, the
modeler has two options. The first is to cut out and remove the coal load entirely and replace it with a flat sheet of

0.060" or thicker styrene and then proceed as described above for the flat decked tenders.
Alternatively, a sub-deck can be fabricated from 0.060" sheet styrene such that it fits below the coal load tightly

against the tender sides. Cut a large circular opening appropriate for the speaker diameter into the styrene sheet and
then glue the sub-deck to the inside of the tender shell. P erf orate the coal load b y drilling a series of small holes (use
a #50-#60 drill) at random angles between the coal “nuggets”. This way, the sound will be allowed to escape yet the
speaker remains relatively invisible regardless of viewing angle.

The more realistic tenders will have fuel b unkers that prototypically e xtend to the tender floor. F or larger tenders with
such a feature, the speaker is best mounted on the tender floor. For smaller tenders, the slope sheet and interior
walls will not only interfere with the speaker, but the decoder as well and it will usually be necessary to remove and
replace them with sheet brass or styrene to create a flat decked tender.

Tender Floor Modifications

If you are mounting the speaker to the tender floor, first determine the exact speaker location within the tender and
verify that there is adequate clearance between the tender body and speak er magnet. Use a marker or scribe to note
the location of the speaker on the tender floor and then drill three rows of holes (see Figure 5) in the pattern shown
to provide an opening for the sound to escape. A drill appro ximately .250" is a good size. Space the holes as best y ou
can, taking into consideration the tender underbody detail. Although the spacing is not critical, you should attempt to
provide at least this much of an opening. If necessary , use more holes of a smaller diameter. Keep all the holes within
the expected cone area of the speaker. Take care not to place holes at the outer edge of the speaker assemb ly itself.

Once you hav e drilled your holes, remo ve all b urrs and une v en edges. Makes sure there are no metal burrs or edges
projecting up - the speaker floor should be smooth, with nothing to physically interf ere with the speaker’s ability to lay
completely flat on the tender floor, such as solder joints, screw bosses, and mounting studs.

Figure 5 - Tender Floor Modifications

Speaker
Cone Area

Secure the Speaker in Place

Once body work is complete and the speaker has been fitted in place, it must be secured tightly to the enclosure. F or
the best sound, an airtight seal is needed around the speaker edge and we have found the best way to hold the
speaker in place is to use silicone RTV - it provides the air tight seal needed and unlike epoxy or other hard glues,
allows the speaker to be readily remov ed in the future . Be careful that you don’t get any RTV onto the speaker cone
itself as this will severely distort the sound quality!

Step 6. Install the Lamps

Headlights, Backup Lights and Mars Lights
Drill out the headlight castings to accept any lights you intend to use, including the tender backup light. If you are
using Throttle Up!’s 1.5V, 1.3mm microbulbs, P.N. 810022, a #53 twist drill mak es a perf ect hole . If you are using the

Digital Sound Decoder Owner's Manual

11

larger, 2.5mm microbulbs, P.N. 810024, a #41 twist drill works well.
Test fit the microbulb for adequate hole clearance and enlarge the hole if necessary. Next, paint the headlight

castings’ reflector surface with white or silver paint and allow to dry.
Install the light bulbs and secure in place using tape or a flexib le glue that does not bond w ell to glass such as white

glue, rubber cement or RTV. Epoxy or ACC glues will make bulb replacement very difficult and are not recom­mended.

As a final touch, install a lens using white glue to hold it in place. You may wish to use a commercially available lens
such as those offered by MV Lenses or mak e your o wn. A lens can be easily f abricated from a sheet of clear styrene
or alternatively, molded from a drop of clear epoxy that is allowed to flatten and harden on a non­stick surface.

Firebox Lights
The firebox lights should first be colored with a THIN coat of orange paint followed with a few streaks of red and
yellow. Testors makes a variety of transparent candy enamels for automobile modelers that work well for this pur­pose. Alternatively, you can use red or orange LEDs in which case painting is unnecessary.

The firebox light should be mounted between the locomotive frame rails in the general vicinity of the ash pan. The
idea is that the bulb is never directly visible but rather casts a gentle glow onto the ground below. The bulb may be
held in place with tape or silicone RTV.

If you are using the Intelligent Firebox Flicker effect, you may wish to modify the locomotive’s firebox door so it is
slightly open and then mount the bulb directly behind it. In this manner , when Fireman F red puts a f ew scoops of coal
into the fire, the cab will fill with a soft orange glow.

Step 7. Install the Exhaust Cam

If you are intending to synchronize the steam exhaust chuff using a mechanical cam switch, you have a little more
work to do! Otherwise, if you are planning to use the DSD’s Auto-Exhaust feature, you may skip this step.

Throttle Up! offers its P.N. 810038 Exhaust Cam Kit as an easy to install alternative to traditional axle mounted sound
cams. The Exhaust Cam set provides nine different synchronizer disks of varying diameters and configurations.
Installation is straightforward and unlike the traditional sound cam, has the advantage that the drive wheel does not
need to be removed from the axle.

Begin by selecting the synchronizer disk pattern appropriate for your engine:

(Optional)

2-Cylinder Steam Locomotives

In all conventional 2-cylinder steam engines , use a synchronizer disk with 4 foil segments. You
can achieve the proper prototypical exhaust chuff timing by aligning the foil strips of the syn­chronizing disks to the crank pin on the driver wheel.

Articulated Steam Locomotives

Articulated engines come in two flavors, simple and compound. On simple articulated engines,
the cylinders on the front and rear are the same size. On compound engines, one set of cylin­ders is considerably larger than the second set.

For compound articulated engines, 4 chuffs per driver revolution is correct. Install the same as
for regular locomotives.

For simple articulated engines, a synchronizer disk is av ailable that pro vides 8 chuffs per driv er
revolution.

Geared Locomotives

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Digital Sound Decoder Owner's Manual

Geared engines require a larger number of chuffs due to multiple cylinders and gearing of the
drive wheels. Due to the large number of contacts required f or each wheel re v olution, it is usually
impractical to achieve the prototypically correct number of exhaust chuffs per revolution. The
Shay disk (supplied with the Exhaust Cam set) will provide a reasonab le compromise. Optionally,
you may elect to use the Auto-Exhaust feature.

Install the Synchronizer Disk

Carefully measure the diameter of your locomotive's driv er axle. Drill a hole of the same diameter
in the center of the synchronizer disk you plan to use.

Note: the thin disk material will be easier to drill if you
temporarily adhere it to a smooth wood block with a water soluble glue. The disk can be separ ated from the b lock by
soaking in water after the drilling operation is complete.

Be sure to use a sharp drill to get a clean burr-free hole.

Once the hole is drilled, check that there is still enough foil at the 'hub' to connect all the spok es together. If not, you
will need to use a synchronizer disk with a large hub.

Cut the disk out with a sharp pair of scissors, and trim the disk diameter to slightly less than the locomotive drive
wheel diameter. This is important as clearance will be needed to clear turnout frogs, guard rails, and other trac kwork
features.

Using the scissors, make a single radial cut in the disk between the foil spokes from the outer edge to the center
hole.Slip the disk over the driv e axle with the insulated side f acing against the drive wheel. Check f or a correct fit and
make any needed adjustments. The disk should fit flush against the drive wheel and there should be a close fit
against the axle. Once you are satisfied with the fit, glue the disk against the

non-insulated

drive wheel with epoxy or

contact cement.
You will need to electrically connect the sychronizer disk to the drive wheel axle. This is best done by soldering the

axle to the foil hub. Alternatively, you may use conductive paint to make the connection.

Figure 6 - Synchronizer Disk Installation

2. Glue disk to
uninsulated
driver

1. Cut and trim
disk to fit

3. Solder disk
hub to axle

Install the Cam Wiper

Using the spring wire supplied with the Exhaust Cam set, fabricate a contact wiper. Bend the wire to match the
pattern of Figure 7 using a pair of needle nose pliers.

Figure 7 - Cam Wiper Fabrication

1. Bend spring wire
to this shape.

2. Solder to
mounting PCB

Solder the wiper to the small printed circuit board base as shown in Figure 7. Keep the spring wire as long as possible

Digital Sound Decoder Owner's Manual

13

to provide flexibility. If the wire is too short, it will rub against the synchronizer disk with excess force causing
premature wear and possible binding.

Temporarily mount the insulated side of the wiper base to the locomotive frame such that the wiper end barely rubs
against the synchronizer disk and does not touch any other part of the locomotive. Referring to Figure 8, adjust the
spring wire so that the contact point is centered directly below the axle and its plane is parallel with the top of the rail.
Once the wiper has been properly adjusted, move the wiper base until the spring wire is deflected by about 1/32" to
1/16" and secure the base in place with epoxy.

Figure 8 - Contact Wiper Alignment

Step 8. Install and Wire the Decoder

Begin by securing the decoder in place using double sided f oam tape . Temporarily refit the body shell to ensure that
adequate clearance still exists.

When wiring the decoder, trim all wires to reduce unnecessary lead length. This will not only give your installation a
neater appearance but also prev ent wires from interfering with the drive mechanism and getting pinched betw een the
frame and body shell.

To ensure long-term reliability, solder all connections and insulate with heat shrinkable tubing. Throttle Up! has heat
shrink tubing available for this purpose, Item no. 810036.

A separate connector should be used for the cam s witch (if used) and wired to a P.N. 810058, single-pin connector.
It is also recommended that the female end of all connectors be wired to the decoder side of the harness. If the

connector becomes unplugged, it is less likely for the female end to inadvertently come in contact with a potentially
harmful electrical signal.

Motor and Power Connections

The DSD wires uses two wire harnesses color-coded per the NMRA Standard:

POWER, MOTOR AND LIGHTS (9-Pin Connector Pin-outs)

1 GREEN F1 Power Sink
2 RED Right Hand Rail Power Pickup
3 ORANGE Motor (+) Terminal
4 BLUE Function Common (+Raw)
5 WHITE Headlight Power Sink
6 YELLOW Backup Light Power Sink
7 GREY Motor (-) Terminal
8 BLACK Left Hand Rail Power Pickup
9 BROWN F5 Power Sink

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Digital Sound Decoder Owner's Manual

SPEAKER AND CAM (3-Pin Connector Pin-outs)

10 PURPLE Speaker (-)
11 BROWN Cam Input
12 PURPLE Speaker (+)

Speaker -

­ +

Speaker +

100

µF

16V

47-100

µF

16V

(Diesel)

DSD Pinouts

Function 5 Output

Backup Light

Headlight
Function 1 Output

Function Common

Brown

Yellow

White

Green
Blue

Motor +

Orange

9
6

5
1
4

Motor -

Gray

Purple

121073

Purple

11

8

2

Brown

Black

Red

Right-hand Rail Pickup

Cam

Left-hand Rail Pickup

(end View)

Figure 9 - Master Wiring Diagram

Referring to the master wiring diagram (Figure 9), begin with the power connection.

1. Connect the decoder’s RED wire to the right hand rail power pickup (typically the locomotive frame).

2. Connect the decoder’s BLACK wire to the left hand rail power pickup (typically the tender pickup)

3. Connect the decoder’s orange wire to the motor’s (+) brush terminal.

4. Connect the decoder’s gray wire to the motor’s (-) brush terminal.

9

8

7

6

5

4

3

10

2

11

1

12

BE ABSOLUTELY SURE THAT THE CONNECTIONS TO THE MOTOR ARE ISOLATED FROM EVERY­THING OTHER THAN THE DECODER CONNECTIONS DESCRIBED ABOVE, AND MAKE SURE THERE

ARE NO SHORT CIRCUITS.

Speaker Connections

5. Connect the decoder’s PURPLE wires to the plus and minus ter minals on the speaker. If you have installed

multiple speakers, make sure they are phased properly, i.e., positive lead to positive lead and minus lead to
minus lead of each speaker.

A 100µf, 16V capacitor must be wired in series with the speaker (+) wire (pin 12) for steam DSDs. Use either
a 47uF or 100uF, 16V capacitor for the diesel DSDs. The positive (+) lead of the capacitor should connect to

the DSD wire. The negative (-) capacitor lead should connect to the speaker as shown in Figure 9.

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15

Lighting Outputs

Each DSD is equipped with four function outputs that are intended to drive headlight, bac kup light and special eff ect
lights. Each output is rated for 100mA.

Do not exceed this rating! Be sure that the combined current of all lights as well as the motor stall current
measured in Step 1 does not exceed the decoder rating.

The lamps may be wired for one of two modes of operation: full-wave and half-wave. Full-wave operation is the
preferred wiring method and supplies power to each lamp via the common BLUE wire. The advantage of the full­wav e wiring scheme is that the lamp brightness will be unaffected when the lay out is operating another locomotiv e in
analog mode.

HALF-WAVE LAMP WIRING METHOD FULL-WAVE LAMP WIRING METHOD

12-16V Lamps

Forward

Lamp

Forward

Lamp

Forward

Lamp

WHITE

560 ohm
Resistor

WHITE

Cathode (-)

640 ohm
Resistor

WHITE

Reverse
Lamp

Right Hand Rail Pickup

Left Hand Rail Pickup

YELLOW

Right Hand Rail Pickup

Reverse

Lamp

YELLOW

Right Hand Rail Pickup

Reverse

Lamp

Cathode (-)

YELLOW

Left Hand Rail Pickup

560 ohm
Resistor

Left Hand Rail Pickup

640 ohm
Resistor

1.5V Microbulbs

LEDs

Forward

Lamp

Forward

Lamp

Forward

Lamp

WHITE

560 ohm
Resistor

WHITE

Cathode (-)

640 ohm
Resistor

WHITE

FUNCTION COMMON

Reverse
Lamp

Reverse

YELLOW

Reverse

Lamp

YELLOW

FUNCTION COMMON

Lamp

FUNCTION COMMON

560 ohm
Resistor

Cathode (-)

640 ohm
Resistor

YELLOW

BLUE

BLUE

BLUE

Figure 10 - Lamp Wiring Diagram

The half-wave wiring method has the advantage that the BLUE common wire is not used meaning there is one less
wire connection to the decoder which may be an issue when installing the DSD into smaller locomotives . The primary
drawback is that lamp brightness will change when operating another locomotive in the analog mode.

The DSD lighting outputs may be used with 12-16 volt incandescent lamps, 1.5 volt microbulbs or LEDs. If you are
using the DSD to drive 12-16V lamps, each bulb can be directly wired to the function outputs as shown in Figure 10.
If the lamps draw more than 50mA, wire a 22 ohm, 1/4W resistor in series with each lamp to prev ent the lamp start-

16

Digital Sound Decoder Owner's Manual

up currents from overloading the decoder outputs.
If you are using the DSD to drive 1.5V microbulbs, it will be necessar y to wire a small current-limiting resistor in

series with each of the lamps to prevent them from burning out. A 560 ohm, 1/4W resistor is recommended for use
with Throttle Up! P.N. 810022 or 810024 microbulbs, however, you may need to adjust this value to get the desired
brightness depending on the output voltage of the command station. Lower resistances will increase the brightness
of the lamp.

The DSD may also be used with LEDs, which also require a resistor , typically about 680 ohms , 1/4W . Note that LEDs
are sensitive to polarity. The minus (cathode) end of the LED is connected to function output and the plus (anode)
end is wired to the decoder’s BLUE or common wire.

Note: LEDs are not recommended for use with the Mars Hyperlight effect.

1. To wire the Headlight, connect one end of the bulb (or cathode of an LED) to the decoder’s WHITE wire. Wire the

other bulb lead to the decoder’s BLUE wire for full-wave operation. For half-wave operation, the other bulb lead
may be connected to either the left or right hand rail power pickup as convenient.

2. To wire the Backup light, connect one end of the bulb (or cathode of an LED) to the decoder’s YELLOW wire. Wire

the other bulb lead to the decoder’s BLUE wire for full-wave operation. For half-wave operation, the other bulb
lead may be connected to either the left or right hand rail power pickup as convenient.

3. To wire the Function 1 output, connect one end of the bulb (or cathode of an LED) to the decoder’s GREEN wire.

Wire the other bulb lead to the decoder’s BLUE wire for full wave-operation. For half-wave operation, the other
bulb lead may be connected to either the left or right hand rail power pickup as convenient.

4. To wire the Function 5 output, connect one end of the bulb (or cathode of an LED) to the decoder’s BRO WN wire.

Wire the other bulb lead to the decoder’s BLUE wire for full wave-operation. For half-wave operation, the other
bulb lead may be connected to either the left or right hand rail power pickup as convenient.

Any outputs not used can be left disconnected, but you should cut off and insulate the ends of the wires so they do
not come in contact with locomotive or locomotive wiring.

Cam Connections

1. Connect the decoder’s BROWN wire from the 3-pin Speaker/Cam Connector (pin 11) to the cam wiper switch.
This completes your wiring! Double check all y our wiring and verify that all joints are insulated and there are no short

circuits. Be sure that BOTH motor brush connections are completely isolated from all connections other than to the
decoder’s Orange and Gray wires.

Reassemble the locomotive. Be sure that no wires are pinched between the assemblies and that there is no interfer­ence with moving parts that could causing chafing and shor t circuits in the future.

Step 9. Test the Installation

Now you are ready f or the test trac k! W e recommend y our test trac k be fused with a f ast-blo fuse appropriately rated
for your decoder (i.e. 1 amp decoder, 1 amp fuse). Place the locomotive on the track, and turn on power to the
system. Set your controller so commands are sent to locomotive address 03.

You should hear the firebox blower and the airpumps running and be able to run the engine in both directions as well
as turn the lights on and off with the function keys. If the locomotive does not travel in the appropriate direction, you
have reversed the polarity of the motor brush connection. Turn the power off , switch the ORANGE and GRAY motor
leads and try again. If e v erything seems OK at this point, it is time to program the decoder’s Configuration Variables
to get the desired sound and lighting effects.

Step 10. Programming the CVs

The final installation step (At last!) is programming the DSD’s Configuration Variables or CVs.

Digital Sound Decoder Owner's Manual

17

What is a CV?

CV stands for Configuration Va riable which is the industry adopted term for a decoder’s user-programmable memory
locations. CVs allow you to customize individual decoder properties such as the address, momentum, throttle re­sponse, sound volume and much, more . Once a CV has been programmed, it will be permanently remembered ev en
after the power has been turned off. A CV can be modified as often as necessary by simply reprogramming it with
a new value.

The NMRA has defined over 70 standard CVs and their usage in RP-9.2.2. Most of these CVs have been uniformly
implemented by the various DCC component manufacturers including SoundTraxx resulting in a high degree of
interoperability, particularly with products designed after July , 1995 when the standards and recommendations were
formally agreed upon. F or e xample, the decoder’s primary address is always stored in CV 1. Be aw are that there are
also a number of CVs which have been designated as “Reserved for Manuf acturer Use” allowing the manufacturer to
add a feature that is unique to their products. The SoundTraxx DSD has several such CVs used primarily for custom­izing the sound and lighting effects.

With the large number of CVs available, first inspection of the available options may cause confusion and perhaps
even a br ain-cramp! Take an aspirin and relax.

The DSD has been shipped with all CVs pre-programmed so you can begin using your locomotive
immediately without having to worry about what adjustments to make.

T able A summarizes the DSD’s default operating characteristics as shipped. Simply set your controller to address 03

and away you go! Be sure to also set your controller for 28 speed step mode or the headlights may not operate as
expected.

Table A.

SoundTraxx DSD Default Operating Characteristics

Address = 03
Vstart = 7
Acceleration = 0
Braking = 0
Consist Addressing = Off
Speed Steps = 28
Speed Tables = Not used
Lighting Control = Automatic Direction Control
F1 Effect = On/Off
F5 Effect = On/Off

Audio Volume = 50%
Background Sounds = All on.
Exhaust Synchronization Source = Exhaust Cam

Function Mapping:

FL = headlight (forward) and Backup (reverse) Light On/Off
F1 = F1 Function Output
F2 = Whistle
F3 = Bell
F4 = Hiss
F5 = F5 Function Output
F6 = Dynamo Sound On/Off
F7 = Coupler Sound Trigger
F8 = Audio Mute

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Digital Sound Decoder Owner's Manual

After awhile, you will probably want to make some changes such as selecting a new address or changing a sound
effect. The following paragraphs break the DSD’s CVs into various subsystems so it is only necessary to change a
few CV’s at a time. As you become comfor table with the DSD’s operation, move onto a new section and begin
exploring the options and capabilities found there. Detailed information on any CV can be found in the DSD T echni-

cal Reference located in Part II of this manual.

Bits and Bytes

One of the most confusing aspects of programming a CV is figuring out what the all the different bits, bytes and x’s
found on the various decoder manuals (including this one) mean. The prob lem is compounded further by differences
in each command station manufacturer’s user interface. For those users unfamiliar with such terms, a shor t math
lesson (ugh!) is in order before proceeding:

Each decoder CV stores a numeric value that can be represented in one of three forms:

Decimal - This is the form we are all familiar with and use in our day-to-da y lives. Numbers are represented
as a sequence of digits composed of the numerals 0,1,2,3,4,5,6,7,8, and 9.

Hexadecimal - Also referred to as simply “hex”, this is a more specialized number representation that, in
addition to 0 through 9, also uses the characters A-F. It has the adv antage that a giv en decimal n umber can
be more compactly represented. For example, the decimal number 127 is simply 7F in hex (one less digit).
This allows user interfaces with a limited number of digits to display a wider range of numbers.

Binary - Binary numbers get their name from the fact they use only two digits 0 and 1 called ‘

bits

’ and is the
fundamental number system used by all computers including the ones found inside a digital decoder. Be­cause there are only two bit values, it takes more digits to represent a number using binary. The decimal
number 127, for example, is written as 01111111 in binary notation. A ‘
eight bits. And a ‘

nibble

’ is half a byte or four bits. Really! We didn’t make that up.

byte

’ is a binary number made up of

Coincidentally, each CV is made up from one byte or eight bits and can store any number betw een 0 and 255. Most
of the CVs contain a single piece of data that can be easily represented in any of the three forms. i.e., CV 3, the
acceleration rate, can be loaded with any value from 0 to 255 and it always aff ects the same thing - the acceleration
rate.

On the other hand, some CVs use individual bits to represent different v ariables. This allows a CV to hold up to eight
individual variables within a single b yte and is done in order to conserve the numbers of CVs. As the bit v ariables can
take on only one of two values 0 and 1 they are usually used for simple variables that are either On or Off, enabled
or disabled or something similar. Unfor tunately, bit variables are difficult to represent in any form other than binary
and still preserve any meaning. Because most DCC system user interfaces don’t use binary representation, these
numbers are the most difficult to work with and require a tedious series of additions to convert to the decimal or hex
form used by most systems.

Whenever possible, we have tried to use the decimal number system in this manual when describing the proper
values to program into a given CV. For users of those systems that use hexadecimal numbers, we have shown the
hex equiv alent in parenthesis. Throughout this man ual, a hex number can be distinguished from a decimal number b y
noting a 0x prefix. Thus 0x10 is the hex version of sixteen and not ten as one might guess. Binary numbers are
represented using a ‘b’ suffix. 100b is thus the number four and not one hundred.

To fur ther assist the math-impaired user, we have provided a handy-dandy conversion table in Appendix C that
allows one to quickly convert between decimal, hex and binary.

When working with bit variables such as CV 29, we suggest the f ollowing procedure f or determining the correct value
to program. Ref erring to the CV description, write down from left to right, the value of each individual bit. Consider f or
example, the case of CV 29. We would like to set this CV so the speed tables are enabled and the 28 speed step
mode is in effect. Referring to page 21 in the DSD Technical Reference, we see that bit 4 and bit 1 should be set to
1 and all other bits are cleared to 0. Starting with bit 7 and working to the right, we write down the individual bit values
and get:

Digital Sound Decoder Owner's Manual

19

bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

We then look up the v alue Binary value 00010010b in Appendix C and see that it corresponds to the decimal value
18 (0x12 in hex). This is the value to use when programming the CV.

Programming Procedure

There are six methods for programming the DSD which fall into one of two classifications:
Service Mode Programming - These progr amming modes usually require the locomotive to be placed on a special

programming track or connected to a dedicated programmer. There are four types of service mode instructions:

Address Mode - Can change CV 1 (Primary Address) only.
Register Mode - Can change CVs 1,2,3,4,7,8 and 29 only.
Paged Mode - Uses a page register to indirectly modify any CV.
Direct Mode - Can directly change any CV.

Operations Mode Programming - Sometimes called ‘Ops Mode’ or ‘Programming on the Main’, these program-
ming modes allow the CVs to be changed while the locomotive is operating on the layout even when other locomo­tives are present. The neat thing about these modes is that the CVs can be changed in the middle of operation
allowing the engineer for example, to change the increase the momentum rate of a locomotive after it couples to a
train. There are two forms of this programming mode:

Operations Mode Short Form - Uses an abbreviated packet format and allows only CV 23 and 24 (consist
acceleration and braking) to be modified.

Operations Mode Long Form - Allows any CV to be modified.

Note: The DSD imposes the restriction that CV 1, CV 17 and CV 18 cannot be changed in this mode to
prevent accidental modification of the locomotive’s address during operation.

It is important to realize that not all programming modes will program all CVs. The DSD T echnical Reference lists
the programming modes that may be used for each CV.

The specific programming mode you use will depend upon the type of DCC system you are using. Some of the ne wer
DCC systems can automatically select the proper programming mode so all you need to do is specify the CV number
and its new value . On the other hand, some systems support only a fe w of the programming modes and ma y restrict
which CVs you can program. If in doubt, refer to your DCC system’s manual or contact the manufacturer to deter-
mine which methods they support.

If you hav e troub le reading or verifying CVs, the prob lem ma y be due to the design of your command station and not
the DSD itself. The DSD and all other decoders communicate back to the command station using what's called an
acknowledgement pulse, which is defined in NMRA RP-9.2.3 as "an increased load on the progr amming tr ack of at
least 60mA for at least 50ms." Lik e most decoders, the DSD gener ates the ac knowledgement pulse b y momentarily
applying power to the motor . You can often visually verify that the DSD is properly responding to your programmer by
observing a slight twitch in the motor shaft when a read or write command is given.

If your DSD is otherwise working properly (i.e., responds properly on the mainline to speed and direction commands)
but your command station is having troubles reading CV data from the DSD, it may be due to incompatibilities
between the electrical requirements of the DSD (which are different from conventional decoders due to the added

20

Digital Sound Decoder Owner's Manual

audio circuitry) and the electrical characteristics of your programming track. In such an ev ent, we suggest y ou simply
go ahead and program the data into the CVs anyway. Usually the DSD will accept the data and function properly
when it's placed back on the main track. You can also try a different programming mode. If your system supports it,
the best way to program the CVs is Oper ations Mode, as it allo ws y ou to immediately see or hear the results of y our
changes.

As each DCC system is different, the specific procedure for prog ramming a CV will vary depending upon the system.
We have summarized the basic programming steps for several of the most popular systems below. For more infor­mation, as well as programming procedures for all other systems, please consult your DCC system manual.

Digitrax Chief and Big Boy

1. Place the locomotive on the programming track.

2. Press the RUN/STOP and FUNC buttons together until the PROG light glows green.

3. Turn the left throttle knob until the left hand numbers on the LCD displa y correspond to the CV number you wish
to change.

4. Turn the right throttle knob until the right hand numbers on the LCD correspond to the value you wish to program
into the CV selected in step 3.

5. Press the SEL/SET button to store the new value into the CV.

6. Repeat steps 3-5 until you are finished programming the CVs y ou wish to change.

7. To exit the programming mode, press the RUN/STOP and FUNC buttons together until the PROG light turns off.

Note: The Digitrax Chief also supports Operations Mode Programming. See your owner’s manual for more
information.

Wangrow System One

1. Place the locomotive on the programming track.

2. Press the PROG MODE key several times until the display shows USE PROGRAM TRK.

3. Press the Enter key. The display will show 1=STD 2=CV 3=REG.

4. Press the 2 key. The display will show ENTER CV NUM:

5. Enter the number of the CV you wish to change and press ENTER.

6. After a moment, the display will show the current value of the CV.

7. Enter the new value for the CV and press ENTER.

8. Repeat steps 5-7 until you are finished programming the CVs you wish to change .

9. Press the PROG MODE button to exit the programming mode and return to nor mal operation.

Note: The System One also supports Operations Mode Programming. See your owner’s manual for more
information.

Lenz Digital Plus, Version 2.1

1. Place the locomotive on the programming track.

2. To activate the programming mode, press F, 8, and ENTER.

3. Press the ENTER key again and the display will show CV.

4. Press the ENTER key again and the display will show SEARCH and after several seconds should show the
Manufacturer ID for Throttle Up! as MF 141.

5. Press any key seven times until the display shows C_.

6. Enter the number of the CV you wish to change and press ENTER twice.

7. After a moment, the display will show the current value of the selected CV.

8. Enter the new value for the CV and press ENTER.

9. Repeat steps 6-8 until you are finished programming the CVs you wish to change .

10. Press the ESC button to exit the programming mode and return to normal operation.

Note: When using the Lenz Digital Plus’s binary display mode, remember that it shows binary numbers with bit
0 on the left and bit 7 on the right which is opposite to normal convention and as used in this manual. Lenz does

not currently support Operations Mode Programming. See your owner’s manual for more information.

Digital Sound Decoder Owner's Manual

21

Configuring the Address

The first group of CVs you will want to change are those that set the DSD’s address:

CV 1, Primary Address
CV 17:18, Extended Address
CV 29, Configuration Data

The DSD may be set up to recognize either the primary address which provides a range of 1 to 127 or the extended
address which has a range of 1 to 9999! Whether you use the primar y or extended address will first depend on
whether or not your DCC system uses long addresses (not all of them do- if in doubt, see your owner’s manual.)
Second, it will depend on your preferences and the n umbering scheme you use f or setting y our decoder addresses.
The extended address has the advantage that you can use all four digits of a locomotive’s road number for the
decoder address making it easy to remember.

Note: The primary and extended addresses can only be set in service mode.

Primary Address

To use the pr imary address, simply set CV 1 to the desired address between 1 and 127 (0x01-0x7F).

Extended Address

The extended address is actually made up of two CVs, 17 and 18. Unless you are an experienced user, you should
not try to program these CVs individually as a specific protocol is required in order for the DSD to accept the new
data (See the DSD Technical Reference for details). Since most command stations that support extended address-
ing will automatically generate the correct protocol, simply follow their instructions for setting the extended address.
Once the extended address is stored in CV 17 and 18, bit 5 of CV 29 must be set to 1 so the decoder will recogniz e
the extended address for mat. Otherwise, the decoder will continue to respond only to its primary address. See the
next section, Configuring the Decoder.

Configuring the Decoder

The next CV you will w ant to changed is CV 29, Decoder Configuration Byte. CV 29 is one of those complicated bit
variables mentioned earlier and is used to set a multitude of decoder characteristics including:

Speed Step Mode - Sets the decoder to use 14, 28 or 128 speed steps (see "Configuring the Throttle", page 22).
Speed Table - Sets the decoder to use speed tables selected by CV 25 (see "Configuring the Throttle", page 22).
Primary or Extended Address - Sets the decoder to recognize its primary address in CV 1 or extended address in CV

17:18 (see "Configuring the Address", above).
Locomotive Direction - Sets whether the decoder will invert direction commands so that the locomotive runs in

reverse when it receives a command to move forward and vice-versa. This operating mode has little use for steam
locomotives but is useful for setting up diesel engines that ran with the long hood section forward.

To assist the novice user, we hav e created Table B that lists the correct value for CV 29 to get the desired oper ating
modes. Simply find the row that has the modes you w ant and program CV 29 with the listed value. The advanced user
should refer to the DSD T echnical Reference for more details.

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Digital Sound Decoder Owner's Manual

Table B.

Quick-Reference T able for CV29 Values

CV 29 Speed Use Speed Address Type Locomotive
Value Steps Tables? Direction

00 (0x00) 14 No Pr imary (CV1) Normal
16 (0x10) 14 Yes Primary (CV1) Nor mal
32 (0x20) 14 No Extended (CV17:18) Normal
48 (0x30) 14 Yes Extended (CV17:18) Normal

02 (0x02) 28,128 No Primary (CV1) Normal
18 (0x12) 28,128 Yes Primary (CV1) Normal
34 (0x22) 28,128 No Extended (CV17:18) Normal
50 (0x32) 28,128 Yes Extended (CV17:18) Normal

01 (0x01) 14 No Pr imary (CV1) Reversed
17 (0x11) 14 Yes Primary (CV1) Reversed
33 (0x21) 14 No Extended (CV17:18) Rev e rsed
49 (0x31) 14 Yes Extended (CV17:18) Reversed

03 (0x03) 28,128 No Primary (CV1) Reversed
19 (0x13) 28,128 Yes Primary (CV1) Reversed
35 (0x23) 28,128 No Extended (CV17:18) Reversed
51 (0x33) 28,128 Yes Extended (CV17:18) Reversed

Configuring the Throttle

There are eight CVs that characterize the DSD’s throttle response and 28 more use to create a custom speed table:

CV 2, VStart
CV 3, Acceleration Rate
CV 4, Braking Rate
CV 9, Motor PWM period
CV 25, Speed Table Select
CV 29, Configuration Data
CV 66, Forward Trim
CV 95, Reverse Trim
CV 67-94, Loadable Speed Table

This may sound like a lot of CVs but don’t worry; it’s not necessary to change all of them if you don’t want to.

Speed Step Mode Selection

As it is a digital system, the DSD splits the throttle voltage ov er its minimum and maximum range into discrete

steps

. The DSD can be configured so there are 14, 28 or 128 individual speed steps. The largest number of steps will

speed

give the smoothest throttle response. Beware that not all DCC systems have the ability to control 28 or 128 speed
steps and your choice will depend upon the capabilities of your command station. The DSD’s speed step mode is
selected by CV 29. Refer to the previous section Configuring the Decoder or the DSD Technical Reference to
determine the correct value for CV 29.

Set the Start Voltage

The DSD provides CV 2, Vstart, to set a starting voltage that is applied to the motor at speed step 1 and is used to
compensate for inefficiencies in the locomotive’s motor and dr iveline. CV 2 may be programmed with any value
between 0 and 255 (0xFF) with each step in value being about 0.5% of the maximum available motor voltage. To

Digital Sound Decoder Owner's Manual

23

calculate the value for CV 2, you can use the formula:

CV 2 = 255 X ------------------------------------

Desired Starting Voltage
Maximum Motor Voltage

If your DCC system supports Operations Mode Programming, an alternative method for setting Vstart is to turn your
throttle to the first speed step and then use the operations mode programming f eature to increase the value in CV 2
until the locomotive just begins to mov e.

Set the Acceleration and Braking Rates

The DSD provides two CVs to simulate the momentum due to train weight. CV 3, Acceleration Rate, controls how
fast the locomotive responds to increases in throttle settings and CV 4, Braking Rate , controls how fast the locomo­tive will respond to decreases in the throttle setting.

Both CVs can be programmed with any value between 0 and 255 (0xFF) with 255 corresponding to the

slowest

acceleration or braking rate. Lower settings yield a more responsive locomotive which is useful for switching. When
both CVs are set to 0, the locomotive will respond nearly instantly to any throttle changes. A setting of 255, on the
other hand, will require

3.8 minutes

for a locomotive to reach full speed from a standing stop!

The DSD’s Dynamic Digital Exhaust feature (see page 28) will be more dramatic with larger CV values and we
suggest setting CV 3 and CV 4 to a minimum value of 16 (0x10) or higher.

If you are using 14 or 28 Speed Step mode, setting CV 3 and CV 4 to any v alue g reater than 0 will also improve the
DSD’s throttle response . While it is accelerating or braking, the DSD interpolates between speed steps so in effect,
your locomotive will respond as if it were being controlled with 128 speed steps . No more sudden lurching from one
speed step to another!

Select the Speed Table

The DSD provides 14 preset and one loadable speed tables which can be used for several purposes:

1. Matching the Auto Exhaust chuffing rate to locomotive speed.

2. Speed matching one locomotive to another.

3. Changing the feel of the throttle. For example, you could configure a switching locomotive so there are more
speed steps available at lower speeds for switching and fewer steps at high speeds where the locomotive is
seldom operated.

4. Compensating for an improperly designed driveline so the locomotive will operate within its prototypical speed
range.

CV 25, Speed Table Select, is used to select which speed curve will be used b y the DSD . CV 25 ma y be programmed
with any value between 2 and 15 (0x02-0x0F) to select one of the preset speed curves shown in Table C, page 24.
The exact throttle response for each cur ve is shown graphically in the DSD T echnical Reference under CV 25.

To select the user loadable speed table, set CV 25 to 16 (0x10).
In order for the speed table selection in CV 25 to tak e eff ect, CV 29 m ust also be progr ammed so the DSD knows to

use speed tables. Refer to the previous section "Configuring the Decoder" or the DSD Technical Reference to
determine the correct value for CV 29.

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Digital Sound Decoder Owner's Manual

Table C.

Speed T able Selection

CV 25 Speed Curve Type

2 (0x02) Straight Line
3 (0x03) Logarithmic Curve 1
4 (0x04) Logarithmic Curve 2
5 (0x05) Logarithmic Curve 3
6 (0x06) Logarithmic Curve 4
7 (0x07) Logarithmic Curve 5
8 (0x08) Logarithmic Curve 6
9 (0x09) Logarithmic Curve 7
10 (0x0A) Exponential Curve 1
11 (0x0B) Exponential Curve 2
12 (0x0C) Exponential Curve 3
13 (0x0D) Exponential Curve 4
14 (0x0E) Exponential Curve 5
15 (0x0F) Exponential Curve 6
16 (0x10) User Loadable Speed Table

Set the User Loadable Speed Curve

If you set CV 25 to select the User Loadable Speed Table, you will also need to design and program the Loadable
Speed Table. The Loadab le Speed Table consists of 28 data points contained in CVs 67 through 94, each defining the

percentage

of motor voltage applied at a give speed step. Each data point can contain a value of 0 to 255 (0xFF)

corresponding to 0 to 100% of available motor voltage.
In 28 speed step mode, each data point directly corresponds to a speed step. In 128 speed step mode, each data

point corresponds to ev ery four and a half speed steps. The motor voltage for intermediate steps are interpolated by
the DSD to produce a smooth curve. In 14 speed step mode, alternate (odd numbered) data points correspond to
speed steps 1-14. Important: all 28 data points m ust be prog rammed

even for 14 speed step mode

or an unpredict-

able throttle response ma y occur while acceler ating or braking.
To create a speed curve, begin b y assuming the DSD will be operated in 28 speed step mode . Don’t worry if you are

using another mode - the DSD will automatically take care of the translation between modes.

1. Start by making a table containing 28 entries - one entry for each speed step.

2. For each entry, record the desired throttle response as a percentage of full speed. i.e., 0 to 100%

3. Compute and record the CV value for each step using the following formula:
Percentage of Full Speed (from Step 2)

CV Value = 255 X -----------------------------------------------------

100

4. Program CV 67 with the value computed in step 3 for the first data entry (Speed Step 1)

5. Program CV 68 with the value computed in step 3 for the second data entry (Speed Step 2)

6. Repeat step 5 for each of the remaining 26 CVs from CV 69 to CV 94 until they ha ve been progr ammed with their

respective values.

Table D may be followed as an example and lists the default CV values already programmed into the DSD.

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25

Table D.

Calculating the User Loadable Speed Table

CV # Speed Step % Full Speed CV Value

CV 67 1 0 0 (0x00)
CV 68 2 4 9 (0x09)
CV 69 3 7 18 (0x12)
CV 70 4 11 28 (0x1C)
CV 71 5 15 37 (0x25)
CV 72 6 18 47 (0x2F)
CV 73 7 22 56 (0x38)
CV 74 8 26 66 (0x42)
CV 75 9 30 75 (0x4B)
CV 76 10 33 85 (0x55)
CV 77 11 37 94 (0x5E)
CV 78 12 40 103 (0x67)
CV 79 13 44 113 (0x71)
CV 80 14 48 122 (0x7A)
CV 81 15 51 132 (0x84)
CV 82 16 55 141 (0x8D)
CV 83 17 59 151 (0x97)
CV 84 18 62 160 (0xA0)
CV 85 19 67 170 (0xAA)
CV 86 20 70 179 (0xB3)
CV 87 21 74 188 (0xBC)
CV 88 22 77 198 (0xC6)
CV 89 23 81 207 (0xCF)
CV 90 24 85 217 (0xD9)
CV 91 25 87 226 (0xE2)
CV 92 26 92 236 (0xEC)
CV 93 27 96 245 (0xF5)
CV 94 28 100 255 (0xFF)

Adjust the Forward and Reverse Trim

The DSD provides two CVs for adjusting or ‘trimming’ the forward and reverse speeds.

CV 66, Forward Trim
CV 95, Reverse Trim

These CVs multiply all data points in the speed tables by a factor of n/128 (n is the CV value) allowing the overall
speed curve to be adjusted up or down without reloading all 28 data points again.

These CVs may contain any v alue betw een 0 and 255 (0xFF). Trim values between 129 (0x81) and 255 (0xFF) will
increase speed curve values between 100% and 200% in 1% steps. Tr im values between 1 and 127 (0x7F) will
decrease speed curve values between 1% and 99%. A value of 128 (0x80) yields a scaling f actor of 1.0 and has no
effect on the speed curve.

Using different values for the forward and reverse trim will yield different forward and reverse speeds.

Adjust the Motor Drive Frequency

Virtually all DCC decoders, including the DSD, drive the locomotive motor using a technique called Pulse-Width­Modulation or PWM. PWM works by alternately switching the motor from full off to full on. If the motor is s witched fast
enough, the speed can be controlled by varying the ratio between the time the motor is on and the time the motor is
off. One drawback to PWM is that it can cause the locomotive to buzz, sometimes quite loudly, at low speeds.

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Digital Sound Decoder Owner's Manual

To mitigate some of this noise, the DSD provides CV 9, Motor PWM Period to control the frequency at which the
motor is switched on and off. By adjusting this CV, one can usually find a drive frequency that is quieter than others.
CV 9 can be programmed with any value between 0 and 230 (0xE6). The DSD Technical Reference (see CV 9)
provides suggestions for selecting a proper value. A value between 170 and 190 works well for most locomotives.

Configuring the Lights and Function Outputs

The DSD has four function outputs used for controlling the locomotive lights. Two of these functions, headlight and
backup light, are always used as on-off outputs.

Setting the Hyperlight Effects

The other two functions, F1 and F5 can be also setup for several special Hyperlight lighting effects using CV 49 as
described under Installation, Step 2.

The table below lists the modes for each output and required CV setting:

Table E.

Setting the Hyperlight Effects

CV 49 F5 Output Type F1 Output Type

0 (0x00) On-off On-off
1 (0x01) On-off Mars Light
2 (0x02) On-off Firebox Flicke r
3 (0x03) On-off Sync. Firebox

4 (0x04) Mars light On-off
5 (0x05) Mars Light Mars Light
6 (0x06) Mars Light Firebox Flicker
7 (0x07) Mars Light Sync. Firebox

8 (0x08) Firebox Flicker On-off
9 (0x09) Firebox Flicker Mars Light
10 (0x0A) Firebox Flicker Firebox Flicker
11 (0x0B) Firebox Flicker Sync. Firebox

12 (0x0C) Sync. Firebox On-off
13 (0x0D) Sync. Firebox Mars Light
14 (0x0E) Sync. Firebox Firebox Flicker
15 (0x0F) Sync. Firebox Sync. Firebox

Configure Lighting Control

The DSD supports two modes of headlight operation:

Automatic Direction Control

Both the headlight and backup lights are turned on and off using the FL function. The DSD automatically s witches the
proper light on depending upon locomotive direction.

“Rule 17” Headlight Operation

This is the more prototypical form of operation and requires the engineer to manually switch each lights on or off
individually. Thus, it is possible for both lights to be on at the same time.

The DSD uses Function Mapping (see Remapping the Functions, below) to determine which mode is used.
For automatic direction control, the headlight is mapped to FL(fwd) by setting CV 33 to 1 (0x01), and the bac kup light
is mapped to FL(rev) setting CV 34 to 2 (0x02).

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27

For Rule 17 Operation the headlight is mapped to both FL(fwd and FL(re v) by setting both CV 33 and 34 to 1 (0x01).
The backup light is remapped to a different function by setting the corresponding function map CV to 2 (0x02). For
this example, let’s use F1. If CV 35 is prog rammed to 2, your controller’s FL k e y would no w control the headlight (in
both directions) and the F1 key controls the backup light.

Configuring the Sound Effects

The DSD provides five CVs for customizing the sound effects:

CV 50, Volume Control
CV 51, Background Sound Configuration
CV 52, Foreground Sound Configuration
CV 54, Auto Exhaust Rate
CV 55, Exhaust Tone
CV 56, Exhaust Volume

Setting the Volume

CV 50 may be programmed with an y value between 0 and 15 (0x0F) to control the o verall v olume of the locomotiv e’s
sound. A setting of 0 will tur n the sound off and a setting of 15 will provide maximum volume.

Setting the Exhaust

CV 54 is used to set the automatic synchronization rate or cutoff rate if cam synchronization is used.
For A uto-Exhaust synchronization, the chuff rate will be generated in proportion to the throttle setting. To select Auto-

Exhaust mode, CV 54 is loaded with any v alue between 0 and 255 (0xFF). Higher values will yield higher chuff rates
for a given throttle setting. The correct synchronization rate may be computed as:

CV Value = 115.9 X ------ X Gear Ratio

SPD
DIA

Where SPD is the locomotive’s top speed in scale miles-per-hour at full throttle and DIA is the locomotive’s driver
wheel diameter in scale inches, and Gear Ratio is the gear ratio for shays and other geared engines. For conven­tional steam engines, use gear ratio =1. The driv er diameter can be easily measured with a scale ruler but remember
to convert the measurement to scale inches.

If you don’t know your locomotive’s top speed, you can figure it out by using a stop watch to measure the time (in
seconds) it takes for the engine to travel over a 1/4 scale mile of track and using the formula:

MPH = -------

900
Time

Note: A 1/4 mile in N = 8' 3"

A 1/4 mile in HO = 15' 2"
A 1/4 mile in O = 27' 5"

For HO, a 1/4 mile is 15 feet, 2". If an engine take 20 seconds to traverse this distance, its speed is 45 MPH.
You can also estimate your locomotive’s top speed and still get pretty good results. A good rule of thumb is to use 45
MPH for freight locomotives and 70 MPH for passenger engines.

If you are using the exhaust cam, use the same formula as above for setting the cutoff rate.
CV 55 is used to set the exhaust tone and may be programmed with any value between 0 and 63 (0x3F). Higher

values will produce a steamier exhaust chuff.
CV 56 is used to adjust exhaust volume when the DDE processor is disab led and may be programmed to any value

between 0 and 255 (0xFF). Higher values will produce a louder exhaust.

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Digital Sound Decoder Owner's Manual

Setting the Background Sound Effects

CV 51 is used to select which background sound effects are active as some may not be suitable for your particular
model (an oil burner for e xample will not have a fireman shoveling coal).

CV 51 can be programmed with any value betw een 0 and 255 (0xFF). Howe v er , each bit in CV 51 controls a diff erent
effect and there are ov er 255 combinations! You will need to use the technique described under Bits and Bytes and
refer to the DSD T echnical Reference to determine the proper value for CV 51. Alternatively, you can calculate the
value for CV 51 with a series of additions as follows:

1. Start with CV 51 set to 0.

2. The intervals at which the background sounds occur are spaced randomly b y a ‘clock’ inside the DSD. This cloc k

can work in scale time so that sounds occur ev ery fe w min utes or in real time so sounds occur every few hours!
To select real time intervals, add one to the value in CV 51. Otherwise, skip to step 3.

3. One of the DSD background sound effect is the sound of Air pumps building up pressure in the train line. If you

want to enable this sound, add 2 to the value in CV 51. Otherwise, skip to step 4.

4. A second DSD background sound eff ect is the sound of Fireman F red building up a good dr aft in the firebox with

the blower. If you want to enable this sound, add 4 to the value in CV 51. Otherwise, skip to step 5.

5. Another DSD background sound eff ect is the sound of Fireman Fred scooping coal into the firebox. He’ll do this

whenev er the loco is brought to a stop and again at random intervals . If you want to enable this sound, add 8 to
the value in CV 51. Otherwise, skip to step 6.

6. Another DSD background sound eff ect is the sound of Fireman F red lubricating the side rods with his pneumatic

grease gun from time to time. If you want to enable this sound, add 16 to the value in CV 51. Otherwise, skip to
step 7.

7. Another DSD background sound eff ect is the boiler pop-valv e blo w off. This is a loud effect that runs for about 10

seconds at random intervals. If you want to enab le the pop valv e sound, add 32 to the value in CV 51. Otherwise,
skip to step 8.

8. The DSD’s Cylinder Blo w Down effect can be oper ated as function key or automatically whene v er the locomotive

comes to a stop. This frees up a function key to use for something else. If y ou w ant to use the A utomatic f eature,
add 64 to the value in CV 51. If you want to use the function key instead, skip to step 9.

9. The DSD background sounds selected in steps 2-8 will run whenever the locomotive is stopped. You can also

silence them without changing individual settings for when the engine is the roundhouse f or example. If you want
the background sounds on, add 128 to value in CV 51 otherwise skip to step 10.

10. Program CV 51 with the new value calculated in steps 2-9.

Setting the Foreground Sound Effects

CV 52 is used to modify certain foreground sound effects. CV 52 can be programmed with any value betw een 0 and
255 (0xFF). However, each bit in CV 52 controls a different effect as with the Background Sound Effects, there are
over 255 combinations! You will need to use the technique described under Bits and Bytes, page 18, and refer to
the DSD T echnical Reference to determine the proper value for CV 52. Alternativ ely, you can calculate the value for
CV 52 with a series of additions as follows:

1. Start with CV 52 set to 0.

2. If you are using the Auto-Exhaust feature with a simple articulated locomotive (both sets of cylinders the same

size) add one to the value in CV 52. This will produce a slightly une ven e xhaust cadence effect. F or all other types
of engines, skip to step 3.

3. The DSD features a Dynamic Digital Exhaust (DDE) processor that modifies the exhaust sound as the engine

load changes. To activate the DDE processor, add 2 to the value in CV 52. Otherwise, skip to step 4.

4. If you are using the exhaust cam to trigger the exhaust chuffs, add 4 to the value in CV 52. Otherwise, skip to

step 5.

5. If your locomotive has dual airpumps, add 8 to the value in CV 52 to activate the sound of another pump. If the

engine has only one airpump, skip to step 6.

6. You can also adjust how fast the bell rings over seven steps by adding 0, 16, 32, 48, 64, 80, 96, or 112 to the

value in CV 52. Do not add any other n umber as this may aff ect the settings made in steps 2-4! 0 will produce the
fastest ring rate and 112 will produce the slowest ring rate.

7. Program CV 52 with the new value calculated in steps 2-6.

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29

Configuring for Consist Operation

The DSD supports consist operations and has three related CVs:

CV 19, Consist Address
CV 21, Consist Function Active
CV 22, Consist FL Function Active

The consist CVs allow the DSD to recognize a new address assigned to the consist without changing the primary or
extended addresses. Additionally, they allow each locomotive in the consist to be run as a single unit but with diff erent
function properties.

These CVs are useful when building up a triple header for e xample. Each locomotive in the triple header is assigned
the same consist address by programming CV 19 with the consist address between 0 and 127 (0x7F). If a locomotiv e
is facing backw ards in the consist (unlikely f or steam operations b ut we mention it anywa y), it should be programmed
with the same consist address

plus 128 (0x80). If the forward locomotives are set to address 60 for example, the
backwards engine must be set to 60+128 = 188. F ailure to do this will turn the consist into an angry pushme-pullyou
as all locomotives will try to move forward from the perspective of their own cab and a few pulled couplers might
result!

With three engines in the consist, you’ll probably want the headlight function to activate only the lead engine’s light.
And you’ll only want the backup light on the tr ailing engine to work. But y ou probab ly want the firebo x flick er on f or all
three engines. CV 21 and 22 allow you to define ho w each engine responds to function commands sent to the consist
address. CV 21 controls which of functions 1-8 are active when the consist address is enabled and CV 21 controls
the FL function for f orward and re v erse. As each bit in both CVs enable a diff erent function, you’ll need to ref er to the
section on Bits and Bytes, page 18, and the DSD Technical Reference to determine the proper value for each CV.

Note that when the consist address is set, the locomotive will continue to respond to instructions sent to its primary
or extended address except for speed and direction data.

To deactivate the consist address and restore normal operation, CV 19 must be reprogrammed to 0.

Remapping the Functions

Function Mapping Explained

Function mapping allows the DSD’s sound effects and function outputs to be reconfigured to respond to a different
function key input. This especially useful for users who have throttles with less than eight function keys as now they
can pick and choose what effects they can control instead of being restricted to an arbitrary assignment.

There are 10 function mapping CVs - eight CVs, 35-42 are used to assign output control to function keys 1 through
8 respectively.

The other two CVs, 33 and 34 are both for the FL function. CV 33 controls which outputs are on when FL is on
the locomotive is moving forward. CV 34 controls which outputs are on when FL is on

and

the locomotive is moving

and

in rev erse. If the same output is selected in both CV 33 and CV 34, that function will turn on when the FL function is
on regardless of locomotive direction.
As the DSD has more function outputs (for the purpose of discussion, we’ll consider sound effects to be outputs)
than there are function keys, not all keys can control all outputs. The table on page 24 in the DSD Technical
Reference shows which functions can be mapped to which outputs. Note that a function k e y can be set up to control
more than one output and also an output can be controlled by more than one function key. In the second case, the
outputs are logically or’ed to the function keys so that if an output is mapped to two function k e ys, either k e y will turn
that output on, however, the output will not turn off until both function keys have been turned off.

Function mapping is tricky and if the user is not careful, ‘interesting’ things can happen. As each bit in the function
mapping CVs enables a different output, you’ll need to refer to the section on Bits and Bytes and the DSD T echni-

cal Reference to determine the proper value for each CV.

Function Mapping Example

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Digital Sound Decoder Owner's Manual

There are a sev eral throttles on the market that hav e only fiv e function buttons . The following e xample describes one
way to reconfigure the DSD for such a throttle and still maintain access to most of the DSD’s functionality.

We’ll use the FL (F0 on some units) key for turning on the headlight and backup light and use automatic direction
control to select which light is on. Since lights require electricity, we’ll also set the dynamo to come on automatically
when the lights are turned on.

We’ll use the F1 key to turn on both auxiliary function outputs F1 and F5. This mak es particular sense if both outputs
have been setup as a firebox flicker effect

The F2 and F3 keys will be used f or the whistle and bell respectiv ely. The F4 ke y will control the coupler clank sound.
The two functions that had to be given up are the cylinder b low down eff ect and the audio mute function. The cylinder

blowdo wn effect can still be used by enab ling the automatic blowdown eff ect (see Configuring Backgr ound Sounds)
which will produce the effect whenever the locomotive is brought to a stop. The audio mute function can be imple­mented by setting CV 50, volume control, to zero when sound is not desired. Not too bad a sacrifice!

Using the DSD Technical Reference, we look up the proper bits to set for each CV and after a bit of head scratching,
come up with the following list of values:

CV 33 = 129 (0x81), FL(fwd) = headlight and dynamo
CV 34 = 130 (0x82), FL(rev) = backup light and dynamo
CV 35 = 68 (0x44), F1 = F1 and F5 outputs
CV 36 = 8 (0x08), F2 = Whistle
CV 37 = 2 (0x02), F3 = Bell
CV 38 = 32 (0x20), F4 = Coupler
CV 39-42 = 0, Functions not used.

Once these are programmed into the proper CVs, the DSD will e xhibit the functionality described above. T o enable
the Auto-blowdown effect, set CV 51 to 255 (0xFF).

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31

OPERATING THE SOUNDTRAXX DSD

Whew! Now that we’ve installed the DSD and have all the CVs set up, it’s time to run trains! This section is intended
to give you a general f eel f or ho w the DSD is used in operation. We had to make a f e w assumptions on how the DSD
is set up and for the most part, will assume you’ve left most CVs at their def ault settings , particularly the function key
assignments. If you’ve made a lot of CV changes then your DSD may respond somewhat differently.

At the Roundhouse

Press the F1 and F5 keys on y our controller to turn on the firebox flic ker. When the engine is first fired up, you’ll hear
the boiler gently simmering away and the airpumps pounding out a steady cadence as the airline builds up pressure.
Once pressure has been built, the pumps will slow down and eventually come to a stop.

Press the F6 key on your controller to turn on the dynamo . What a racket! But unf ortunately it’s needed to power the
loco’s lights. Speaking of which, press the F0 key to turn the headlight on.

Our engine’s been sitting around awhile and there’s bound to be some condensation buildup in the cylinders. Press
the F4 key to open up the cylinder cocks and blow out the moisture. Press the F4 key again to close the cocks.

It’s time to couple up the train. Press the F2 key and let off three short blasts of the whistle to let everyone know
you’re backin’ up. What? You don’t remember your whistle signals? Get out of the cab and don’t come back until
you’ve memorized Table F by heart. As the locomotive’s coupler hooks into the train, press the F7 button to activate
the coupler sound. The airpumps are pounding away again as the train line fills with air.

After a few minutes, we’re ready to head out onto the mainline. Now it’s time to try out the DSD’s Dynamic Digital
Exhaust (DDE) processor. If your DCC system uses operations mode program, this is a good time to set in a little
inertia. Set CV 3 and 4 to something around 20-30.

On the Mainline

Press the F2 key and let off two short whistle blasts. Push the throttle forward. As the locomotive grunts out a couple
long exhaust chuffs, train begins to mo v e f orw ard. Push the throttle forward some more (what the hec k, turn it all the
way up!) and notice that the train inertia keeps the engine from taking off b ut the e xhaust chuff becomes louder and
more drawn out as the engine struggles with the train weight. As the train builds up speed, bac k the throttle do wn to
the desired setting and you’ll notice the exhaust chuff quiets down a bit as the train has stopped accelerating. Back
the throttle down to zero and the exhaust chuff will really get quiet now that the train is just coasting along.

This is the DDE processor in action! The DDE senses the difference between the actual locomotive speed and the
throttle setting, using the information to adjust the volume, cutoff and timbre of the exhaust chuff. If you slowly
accelerate or brake the train the exhaust chuff will remain relatively constant. If you turn the throttle substantially up
or down, you will hear a dramatic change in the exhaust sound until the train speed has reached the new throttle
setting. The DDE works best when there is a reasonable amount of inertia programmed into CVs 3 and 4. With
substantial amounts of inertia, you can even use the throttle as an exhaust volume control. Note also that a rapid
decrease in the throttle will be processed as a hard brake application and the airpumps will pickup again to restore
‘pressure’ in the airline.

Into the Station

We’ve had some fun on the mainline but now we’re nearing the station. Let off a few long and loud whistle blasts to
let everyone know w e’re here. As the train slows , press the F3 k ey to ring the bell and clear the trac ks. Bring the train
to a stop and press the F3 again to stop the bell.

After a moment, Fireman Fred will open the firebo x doors and shovel a f ew scoops of coal onto the flames to k eep the
boiler ready for the next trip out. Clink! The doors close and it’s time for Fred to take a nap. But he kno ws better than
to snooze for too long and if y ou hang around long enough, you ’ll hear him get up and grease the valv e gear and draft
the firebox. If he lets the boiler get too hot, you’ll even the pop-valves go off. What a noise!

Hey! What’s that other noise? Your spouse is yelling that they’re trying to take a nap too? Uh-oh, press the F8 k e y to
mute the sound until they’re better rested...

32

Digital Sound Decoder Owner's Manual

Table F.

Whistle Signals

Note: • = Short Blast, - = Long Blast

- - • - Approaching Grade Crossing.

(Hold final blast until crossing is reached.)

• - Approaching a bridge or tunnel

• Stop, set brakes

• • Release brakes and proceed forward

• • • Backup

• • • • Request signal from Trainman

ACKNOWLEDGEMENTS

In the process of recording the many locomotive sounds used in the creation of the Digital Sound Decoders, w e'd like
to gratefully acknowledge the assistance of the following groups and organizations:

The Cumbres & Toltec Scenic Railroad

Box 789, Chama, NM 87520
[phone]

The Durango & Silverton Railroad

Main Street, Durango, CO 81301
[phone]

The Georgetown Loop Railroad

P.O. Box 27, Georgetown, CO 80444
[phone]

The Leadville, Colorado & Southern

P.O. Box 916, Leadville, CO 80461
[phone]

The Nevada Northern Railway Museum

P.O. Box 150040, East Ely, NV 89315
[phone]

The Portola Railroad Museum

P.O. Box 608, Portola, CA 96122
[phone]

Digital Sound Decoder Owner's Manual

33

TROUBLESHOOTING

If you should have any difficulties with the operation of your SoundTraxx Digital Sound Decoder, first check this
section for hints on troubleshooting. If you cannot isolate and find a solution for the problem, we suggest that you
write the factory a note describing the problem in as much detail as possible before returning the unit to the factory
(see Service and Warr anty Policy).

The locomotive runs for awhile and then stops.

The decoder may be ov erheating. Be sure the decoder is located where it can dissipate excess heat. Y ou ma y also try
lowering your command station’s track voltage setting.

The sound works for awhile and then stops.

The decoder amplifier may be overheating. Be sure the decoder is located where it can dissipate excess heat. You
can also try lower the volume using CV 50 or your command station’s track voltage setting.

The locomotive doesn’t move.

Be sure the locomotive address matches that of your controller. If the acceler ation CVs are loaded with large v alues,
the locomotive may be also be very slow to accelerate taking almost four minutes to reach full speed.

The decoder and lights work OK but there is no sound.

Check that the CV 50, volume control is not set to zero or that the mute function (F8) isn't on.

The locomotive buzzes when moving at slow speeds.

This is a normal characteristic of virtually all DCC decoders and is an unavoidab le side effect of using PWM (Pulse
Width Modulation) to drive the motor. The buzzing can be minimized by adjusting the drive frequency via CV 9 and
lubricating the motor brushes with a conductive lubricant such as Aero Car Technology’s “Conducta”.

The lights won’t turn on and off.

This is caused when the decoder is set up for 14 speed step operation and the throttle or command station is sending
28 or 128 speed step packets . Reprogram the decoder and/or command station so the speed step modes match. For
more information, see CV 29.

An alternate cause may be that the decoder functions have been improperly mapped to another function key. See
CVs 33 to 42 for more information.

The headlights flicker on and off as the throttle increases.

This occurs when the decoder is set up for 14 speed step operation and the throttle or command station is sending
speed and direction commands for 28 speed step mode. Reprogram the decoder and/or command station so the
speed step modes match. For more information, see CV 29.

The Hiss function does not work.

If the auto blowdown feature is enabled, the hiss function cannot be manually controlled. See CV 51 for more
information.

The Exhaust Chuff does not work.

If you are using the exhaust cam, be sure the wiper is making contact with the synchronizer disk and there is no
buildup of dirt or grease. If you are using the Auto-Exhaust f eature, be sure bit 2 in CV 52 is set to 0. See CV 52 for
more information. If the DDE is disabled (CV 52, bit = 0), be sure exhaust volume (CV 56) is not 0.

The Locomotive Just Sits and Flashes Both Headlights

This indicates that the CV data has become corrupted and all CVs have been reset to their def ault v alues . The DSD
will return to normal operation after about 30 seconds, or if power is turned off and back on. You will need to
reprogram any CVs you previously modified.

34

Digital Sound Decoder Owner's Manual

SERVICE AND WARRANTY POLICY

LIMITED NINETY DAY WARRANTY

The Digital Sound Decoder is warranted by Throttle Up! to be operative and free of defects in materials and
workmanship for a period of ninety (90) days after original purchase date. Defective Digital Sound Decoders which
are received by Throttle Up! during the warranty period will be repaired or replaced free of charge at the option of
Throttle Up!

Exclusions

This warranty does not cover damage resulting from negligent installation, improper operation, over voltage or over
current damage, failure to follow instructions, misuse, unauthorized repairs or modifications, accidents, damage while
in transit to service location, fire, floods, and other acts of God.

Removing the protective shrink tubing from the decoder automatically voids your warranty.
Due to their fragile nature, onboard locomotive speakers are not covered by this warranty. Throttle Up! certifies the

speakers to be operational at time of sale. In the event a speaker is damaged, we will replace them free of charge if
the defective speaker is returned to the factory within five (5) days of purchase. Prevailing retail and shipping charges
will apply after the five day period.

Warranty Procedure

The product must be returned, postage prepaid and insured to the factory for repair. It is advisable to write or phone
the factory for advice before returning the product for service. Include name, street address (We cannot ship to P.O.
Boxes!), daytime phone number, and description of problem. After repairing product we will ship it to your home at no
cost to you.

Important!: Return only the Digital Sound Decoder. Under no circumstances should you send your locomotive (or
other model) to us as we cannot assume any liability for their safe return.

Limits of Liability

The foregoing shall constitute the sole and exclusive remedy of any owner of this product for breach of warranty
including the implied warranties of merchantability and fitness. IN NO EVENT SHALL THROTTLE UP! BE LIABLE
FOR SPECIAL OR CONSEQUENTIAL DAMAGES OR FOR THE REPRESENTATIONS OF RETAIL SELLERS.

Non-Warranty Repairs

Digital Sound Decoders needing repairs after exceeding the warranty period or damaged during installation, will be
repaired at modest cost for parts and labor. Customer will be advised in writing or by telephone of any service
charges before work is begun. The product will be returned to the address specified with a C.O.D. charge for service,
shipping and handling.

For Prompt Factory Service, mail to:
Throttle Up!/SoundTraxx

210 Rock Point Drive
Durango, CO 81301
Telephone [phone]
FAX [phone]

Digital Sound Decoder Owner's Manual

35

FCC STATEMENT

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15
of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses and can radiate radio interference energy and, if not installed
and used in accordance with the instructions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off and back on, the
user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and the receiver.

• Connect the equipment to an outlet or on a circuit different from that to which the receiver is

connected.

• Consult the dealer or an experienced radio/TV technician for help.

You may also find helpful the following booklet, prepared by the FCC: "How to identify and Resolve Radio-TV
Interference Problems." This booklet is available from the U.S. Government Printing Office, Washington, D.C. 20402.

Changes and modifications not expressly approved by the manufacturer or registrant of this equipment can void your
authority to operate this equipment under Federal Communications Commissions rules.

Throttle Up! Corp.
210 Rock Point Drive
Durango, CO 81301
Telephone [phone]
FAX [phone]

36

Digital Sound Decoder Owner's Manual

APPENDIX B - DSD FUNCTIONAL TEST

g

Although each DSD has been fully tested prior to shipment and is ready for installation, we urge you to test your
decoder before installing in your locomotiv e! We hav e de v eloped a simple procedure that assures y ou that the DSD
is functioning as it should before you do the installation. If this is y our first sound or decoder installation, it will give y ou
an added boost of confidence, knowing that as long as you follow the installation instructions...it

In the event you do have a problem, please contact your dealer or Throttle Up! for technical assistance first. We will
gladly refund payment or replace any decoder that does not pass the functional test free of charge provided that
none of the decoder wires have been cut short.

will

work!

Before you get started, we must reiterate ­is functioning properly.

Do not install any decoder that does not pass the Functional Test.

do not shorten any decoder leads

until you hav e v erified that the decoder

Items Needed for the Functional Test

To perform the Functional Test, you will need: A Decoder Test Kit

An NMRA-compatible DCC system
One 8 ohm speaker

Creating a Test Kit

For your con venience , Throttle Up! off ers a test kit, Item No . 829001 which includes all of the items needed f or testing
the DSD, including detailed instructions. If you prefer, you can make up your own kit with some simple parts pur­chased from your local electronics supplier. If you decide to create your own test kit, you will need:

Qty. Description

1 Resistor, 22 ohm, 2 Watt
1 Resistor, 1K ohm, 1/4 Watt
1 Bicolor LED
1 Black Wire
1 Red Wire

Length of small diameter shrink tubing

Preparing the Test Fixture

1. Connect the black wire to the short lead of the LED.

2. Connect one lead of the 1K ohm resistor to the long lead of the LED.

3. Connect the other lead of the 1K ohm resistor to the red wire.

4. Insulate the connections with heat shrink tubing.

5. V erify the LED is working properly by connecting the red lead to the positiv e (+) terminal of a fresh 9 volt battery
and the black lead to the battery’s negative terminal. The LED should glow red. Reverse the leads and note that
the LED color changes to green.

Flat side of LED
(short lead)

Bi-Color LED

1K ohm
Resistor

Insulate connections with
heat shrink tubin

Black Wire

Red Wire

Preparing the Decoder Test Kit

DSD Functional Test Procedure

Follow directions carefully, working on a

non-metallic surface

.
Any NMRA-compatible DCC system will work for the test. Consult your system manual for appropriate operating
instructions.

Digital Sound Decoder Owner's Manual

37

It isn’t necessary to solder any wires together during the test. Simply twisting the wires together will suffice.
We recommend insulating the ends of the decoder leads with electrical tape to prevent accidental shorts during the

testing.

General Hookup

1. Tur n the power to the DCC system off.

2. Select the lowest possible output voltage setting, usually the N-scale setting.

3. Connect the decoder’s purple (pin 10) lead to the negative (-) terminal of the speaker.

4. Connect the other purple lead (pin 12) to the positive (+) speaker terminal. A 100µF, 16V capacitor must be wired
in series as shown in Figure 2.

5. Connect the red lead of the test LED to the decoder’s orange lead.

6. Connect the black lead of the test LED to the decoder’s gray lead.

7. Connect the 22 ohm resistor to one of your DCC system’s track outputs.

8. Connect the free end of the resistor to the Decoder’s red wire.

9. Connect the Decoder’s black wire to your DCC system’s other track output.

Bi-Color LED

1K ohm

Resistor

Red Wire

Black Wire

Speaker -

­ +

Speaker +

100
16V

µF

Brown

Function 5 Output

Backup Light

Headlight
Function 1 Output

Function Common

Brown

Yellow

White

Green

Blue

9

6
5
1
4

Orange

Gray

Purple

121073

Purple

11

8

2

Black

Red

Cam

22 ohm
Resistor

DCC BO

OSTER

TRACK
OUTPUTS

Figure 2 - General Hookup Procedure

Speaker T est

The objective of the Speaker Test is to ensure that the DSD is generating sound.

1. Make sure no other decoder leads are shorted to any other leads. The best way to do this is to simply tape the
other leads out of harm’s way while you are performing the test. Tape them to the non-metallic surface you are
working on until they are needed.

2. Turn on power to the system.

3. Configure your DCC system to send commands to locomotive address 03 using 28 speed step mode.

4. After a moment, you should hear the sound of airpumps and blowers running in the bac kground. If you do not, turn
off power to the system and recheck your connections.

5. Activate Auxiliary Function 2. The Whistle should blow. Activate Auxiliary Function 3 and the bell should begin to
ring.

If the bell and whistle functions do not work, verify that your DCC system is indeed set to address 03. If your system
has dedicated bell and whistle keys, check that they are properly mapped to control Auxiliary Functions 2 and 3.

38

Digital Sound Decoder Owner's Manual

Note:

If the sound becomes erratic or cuts out when the whistle or bell sounds are activated, y ou may need to change
the command station's track voltage setting to a higher le v el. If this is not practical or does not solv e the problem, y ou
may try wiring the decoder's red wire directly to the DCC system's track output and bypass the 22 ohm resistor.
Howe v er, you must be e xtra careful perf orming the rest of the test as the resistor serves to protect the decoder from
accidental short circuits.

If the DSD still does not produce any sound it is possible that the CV settings may have been altered. You may skip
ahead to the Programming Test section and program the following CV to reset all CVs to their default settings:

CV 30 = 02

If this does not work, contact SoundTraxx for a replacement.

Motor Operation Test

The purpose of this test is to verify that the decoder correctly interprets the speed and direction commands that are
received from the command station.

1. Make sure no other decoder leads are shorted to any other leads.

2. Turn on power to the system.

3. Configure your DCC system to send commands to locomotive address 03.

4. After a moment, you should hear the sound of airpumps and blowers running in the background.

5. Select the forward direction and slowly increase the throttle speed. The Bipolar LED will begin to glow red.

6. Now select the reverse direction and slowly increase the throttle. The Bipolar LED should now begin to glow

green. If the LED does not light or change color, first check that the DCC system is set to address 03. Ne xt, v erify
the LED is working properly as outlined under Preparing the Test Fixture, page A-4.

If the LED still does not light or change color, contact SoundTraxx for a replacement.

Exhaust Cam Test

The purpose of this test is to verify proper operation of the DSD’s cam sensor.

1. Tur n on power to the system.

2. After a moment, you should hear the sound of airpumps and blowers running in the background.

3. Locate the brown cam wire(pin 11 of the 3-pin Speaker/Cam connector .

9-pin connector!

). Tap this wire against either rail. As the cam wire makes contact, y ou should hear a chuff sound.

Do not confuse with the brown wire of the

If you do not hear a chuff, it is possible that the CV settings may have been altered in which case you should have
noted a chuffing sound when performing the Motor Operations Test. If this is the case, you may skip ahead to the
Programming Test section and program the following: CV 30 = 02, to reset the CVs.

Then repeat steps 1,2 and 3 above. If you still do not get a response, contact SoundTraxx For a replacement.

Auxiliary Function Output Test

The purpose of this test is to verify that the decoder correctly interprets the commands for the four auxiliary output
functions.

1. Tur n power to the system OFF.

2. Disconnect the test LED from the gray and orange leads of the decoder. Insulate the ends of the gray and or ange

wires with electrical tape.

3. Attach the black lead of the test LED to the decoder’s blue lead.

4. Connect the red lead of the test LED to the decoder’s white lead (head light). Make sure no other decoder leads

are shorted to any other leads.

5. Tur n on power to the system.

6. Using your DCC controller, turn on Function 0 and set the throttle direction to forward. The Bipolar LED should

light. Turn Function 0 off and the LED should turn off.

Digital Sound Decoder Owner's Manual

39

7. Tur n power to the system OFF. Disconnect the decoder’s white wire from the red lead of the test LED. Now
connect the red lead to the yellow decoder wire (reverse light).

8. Tur n on power to the system. Using your DCC controller, turn on Function 0 and set the throttle direction to
reverse. The Bipolar LED should light. Turn Function 0 off and the LED should turn off

9. Tur n power to the system OFF.

10 .Disconnect the yellow lead of the decoder from the red wire of the test LED. Connect the red lead of the test LED

to the decoder’s green lead (F1 output). Make sure no other decoder leads are shorted to any other leads.

11. Turn on power to the system. Using your DCC controller, turn on Function 1. The Bipolar LED should light. Turn
Function 1 off and the LED should turn off.

12. Turn power to the system OFF.

13 .Disconnect the green lead of the decoder from the red wire of the test LED. Connect the red lead of the test LED

to the decoder’s brown lead (F5 output). Make sure no other decoder leads are shorted to any other leads.

14. Turn on power to the system. Using your DCC controller, turn on Function 5. The Bipolar LED should light. Turn
Function 5 off and the LED should turn off.

Programming T est

The purpose of this test is to verify that the decoder correctly accepts programming commands.

1. Tur n power to the system OFF.

2. Connect the red lead of the test LED to the decoder’s orange lead.

3. Connect the black lead of the test LED to the decoder’s gray lead. Make sure no other decoder leads are shorted
to any other leads.

4. If your DCC system requires the use of a programming trac k, disconnect the red and the black lead of the decoder
and reconnect to your system’s programming track outputs.

5. Tur n on power to the system.

6. The DSD supports register, paged, and direct CV access modes. The mode you use will be entirely dependent
upon the DCC system you are using and you should refer to your owner’s manual for further information. Using
your system controller, reprogram CV1, decoder address, to an address other than 03 that is within the range of
your system’s capability. Write down the address that you select.

7. Turn off power to the system.

8. Reconnect the DSD’s red and black leads to your DCC system’s track outputs.

9. Turn on power to the system and reconfigure it to send commands to the address you programmed in step 5.

10 .Now slowly increase the throttle. The Bipolar LED should now begin to glow. This indicates that the decoder has

accepted the address change. If the LED does not light, verify that the locomotive address is programmed to the
address you selected. If it still does not light, contact Throttle Up! For a replacement.

The Functional Decoder Test is complete. You have verified that your decoder is operating as it should and you can
now proceed to locomotive installation!

40

Digital Sound Decoder Owner's Manual

BINAR Y/HEX CONVERSION CHAR T - APPENDIX C

DECIMAL HEX BINARY

(76543210)

0 00 00000000
1 01 00000001
2 02 00000010
3 03 00000011
4 04 00000100
5 05 00000101
6 06 00000110
7 07 00000111
8 08 00001000

9 09 00001001
10 0A 00001010
11 0B 00001011
12 0C 00001100
13 0D 00001101
14 0E 00001110
15 0F 00001111
16 10 00010000
17 11 00010001
18 12 00010010
19 13 00010011
20 14 00010100
21 15 00010101
22 16 00010110
23 17 00010111
24 18 00011000
25 19 00011001
26 1A 00011010
27 1B 00011011
28 1C 00011100
29 1D 00011101
30 1E 00011110
31 1F 00011111
32 20 00100000
33 21 00100001
34 22 00100010
35 23 00100011
36 24 00100100
37 25 00100101
38 26 00100110
39 27 00100111
40 28 00101000
41 29 00101001
42 2A 00101010
43 2B 00101011
44 2C 00101100
45 2D 00101101
46 2E 00101110
47 2F 00101111
48 30 00110000
49 31 00110001
50 32 00110010
51 33 00110011
52 34 00110100
53 35 00110101
54 36 00110110
55 37 00110111
56 38 00111000
57 39 00111001
58 3A 00111010
59 3B 00111011
60 3C 00111100
61 3D 00111101
62 3E 00111110
63 3F 00111111

DECIMAL HEX BINARY

(76543210)

64 40 01000000
65 41 01000001
66 42 01000010
67 43 01000011
68 44 01000100
69 45 01000101
70 46 01000110
71 47 01000111
72 48 01001000
73 49 01001001
74 4A 01001010
75 4B 01001011
76 4C 01001100
77 4D 01001101
78 4E 01001110
79 4F 01001111
80 50 01010000
81 51 01010001
82 52 01010010
83 53 01010011
84 54 01010100
85 55 01010101
86 56 01010110
87 57 01010111
88 58 01011000
89 59 01011001
90 5A 01011010
91 5B 01011011
92 5C 01011100
93 5D 01011101
94 5E 01011110
95 5F 01011111
96 60 01100000
97 61 01100001
98 62 01100010

99 63 01100011
100 64 01100100
101 65 01100101
102 66 01100110
103 67 01100111
104 68 01101000
105 69 01101001
106 6A 01101010
107 6B 01101011
108 6C 01101100
109 6D 01101101
110 6E 01101110
111 6F 01101111
112 70 01110000
113 71 01110001
114 72 01110010
115 73 01110011
116 74 01110100
117 75 01110101
118 76 01110110
119 77 01110111
120 78 01111000
121 79 01111001
122 7A 01111010
123 7B 01111011
124 7C 01111100
125 7D 01111101
126 7E 01111110
127 7F 01111111

DECIMAL HEX BINARY

(76543210)

128 80 10000000
129 81 10000001
130 82 10000010
131 83 10000011
132 84 10000100
133 85 10000101
134 86 10000110
135 87 10000111
136 88 10001000
137 89 10001001
138 8A 10001010
139 8B 10001011
140 8C 10001100
141 8D 10001101
142 8E 10001110
143 8F 10001111
144 90 10010000
145 91 10010001
146 92 10010010
147 93 10010011
148 94 10010100
149 95 10010101
150 96 10010110
151 97 10010111
152 98 10011000
153 99 10011001
154 9A 10011010
155 9B 10011011
156 9C 10011100
157 9D 10011101
158 9E 10011110
159 9F 10011111
160 A0 10100000
161 A1 10100001
162 A2 10100010
163 A3 10100011
164 A4 10100100
165 A5 10100101
166 A6 10100110
167 A7 10100111
168 A8 10101000
169 A9 10101001
170 AA 10101010
171 AB 10101011
172 AC 10101100
173 AD 10101101
174 AE 10101110
175 AF 10101111
176 B0 10110000
177 B1 10110001
178 B2 10110010
179 B3 10110011
180 B4 10110100
181 B5 10110101
182 B6 10110110
183 B7 10110111
184 B8 10111000
185 B9 10111001
186 BA 10111010
187 BB 10111011
188 BC 10111100
189 BD 10111101
190 BE 10111110
191 BF 10111111

DECIMAL HEX BINARY

(76543210)

192 C0 11000000
193 C1 11000001
194 C2 11000010
195 C3 11000011
196 C4 11000100
197 C5 11000101
198 C6 11000110
199 C7 11000111
200 C8 11001000
201 C9 11001001
202 CA 11001010
203 CB 11001011
204 CC 11001100
205 CD 11001101
206 CE 11001110
207 CF 11001111
208 D0 11010000
209 D1 11010001
210 D2 11010010
211 D3 11010011
212 D4 11010100
213 D5 11010101
214 D6 11010110
215 D7 11010111
216 D8 11011000
217 D9 11011001
218 DA 11011010
219 DB 11011011
220 DC 11011100
221 DD 11011101
222 DE 11011110
223 DF 11011111
224 E0 11100000
225 E1 11100001
226 E2 11100010
227 E3 11100011
228 E4 11100100
229 E5 11100101
230 E6 11100110
231 E7 11100111
232 E8 11101000
233 E9 11101001
234 EA 11101010
235 EB 11101011
236 EC 11101100
237 ED 11101101
238 EE 11101110
239 EF 11101111
240 F0 11110000
241 F1 11110001
242 F2 11110010
243 F3 11110011
244 F4 11110100
245 F5 11110101
246 F6 11110110
247 F7 11110111
248 F8 11111000
249 F9 11111001
250 FA 11111010
251 FB 11111011
252 FC 11111100
253 FD 11111101
254 FE 11111110
255 FF 11111111

Digital Sound Decoder Owner's Manual

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