Zmodell ZDL-MRK-VT98-B User manual

Digital Decoder
for M rklin Class VT 98ä
Rail Bus Trailing Car
User’s Manual
Art. No: ZDL-MRK-VT98-B
Suitable for:
Märklin 88167, 88168, 88171
(only for new version with interior details)
Ver 1.03

Overview
Package contents
● 1x ZDL-MRK-VT98-B digital decoder
● 2x Light boards with 20 mm pre-soldered cables
● 2x 40 mm power cables (1 red, 1 black)
● 2x Light filters
● 1x User’s Manual
Technical data
Operating mode: DCC, MM, SelecTRIX 1, SelecTRIX 2, DC Analog
Max. voltage: 14 V in digital mode, 12 V in analog mode
Power buffer: Built-in 940 µF (2x 470 µF) keep-alive module with thermal and
overvoltage protection
Functions
F0 - Directionally controlled triple warm white headlights and double red rear lights
F1 - Interior lighting
F2 - Switch off headlights/rear lights at the cabin 1
F3 - Switch off headlights/rear lights at the cabin 2
Default address: 3 (DCC), 01 (SelecTRIX)
Rear light (red) Front Light (white)
Common Return (VS)
2x Light boards 2x Power cables 40 mm2x Light filters
1x ZDL-MRK-VT98-B digital decoder board
Track 1
Track 2
Front Light 1
(LV)
Rear Light 1
(AUX1)
Common Return
(VS)
Track 1
Track 2
Front Light 2
(LR)
Rear Light 2
(AUX2)
Common Return
(VS)
Trimmer resistor for adjusting
brightness of interior lighting
2x 470 µF buffer

Installation
IMPORTANT: Soldering work required for installation of this decoder. Soldering
station with adjustable temperature control, soldering iron with thin tip (1-1.5 mm)
and good soldering skills needed for this.
1. Prior to installing the digital decoder, make sure your railbus runs perfectly in
analog mode without flickering of the light.
2. Carefully remove the housing of the railbus from the chassis.
3. Unsolder all wires from the top of the circuit board that is attached to the interior
details insert.
4. Reduce the temperature of the soldering iron down to 200 °C and heat up
pressed plastic pins which hold the circuit board. At the same time, slowly pull the
circuit board upwards, so that it will separate freely.
5. Separate interior details insert from the chassis. To do this, insert a wide slot
head screwdriver, guitar pick either a similar object into the center of the gap
between the black metal weight plate attached to the blue interior details part and
plastic chassis and carefully turn it until the parts separate from each other.
6. Unsolder four cables from to the brass parts attached to the plastic chassis.
Please do it quickly in order not to damage the chassis by overheating.
7. Turn interior details insert upside down. Carefully hock the small circuit boards
with thin slot head screwdriver. One by one, heat up pressed plastic pins that hold
the boards with soldering iron heated up to 200 °C and pry the boards upwards, so
that they will separate completely.
8. Install new light boards with pre-soldered wires that come with a digital decoder
instead of old ones and press them gently until they sit on the pins completely.
Push pre-soldered cables coming from the light boards into the holes under the
circuit boards. Press two plastic pins with soldering iron heated up to 200 °C in
order to fix the light boards in place.
9. Attach supplied light filters onto the ends of chassis with a small drop of glue
(plastic or lasercut) as shown on this picture:

10. Solder 40 mm red and black power cables that come in the package to the brass
plates attached to the chassis as shown on the picture below. Please do it quickly in
order not to damage the chassis by overheating:
11. Push both power cables into one of the holes under the light boards together
with cables coming from the light board:
12. Insert interior details part into the slot in the center of chassis and press it until it
sits on the chassis completely. No need to fix it additionally with glue.
13. Turn the chassis upside down once again. Push all cables coming from the
holes of interior details part through the appropriate holes in the circuit board of
digital decoder as shown on the following picture:
Mounting holes

14. Install the digital decoder board onto the upper pins of interior details part (see
previous picture for reference) and press them with soldering iron heated up to
200 °C in order to fix the circuit board completely.
CAUTION: Digital decoder circuit board is very thin - only 0.2 mm. Making it so thin
is the only way to fit all electronic components in a very limited space inside the
railbus without making irreversible modifications to the model. Please handle the
circuit board very carefully and never bend it!
15. Solder all cables to the pads on the digital decoder board as shown below:
16. Now the electric part of assembly is complete. At this step, do not install the
housing yet, but place the railbus on the track, turn on the command station and
check if all light functions work correctly. You may need to move the chassis
manually on the tracks in order to establish initial electric contact that may be
unstable during very first run.
You may also adjust the brightness of interior lighting at this stage (brightness of
headlights and tail lights can be adjusted later via decoder settings). To do this, use
small slot head screwdriver and adjust the trimmer resistor on the circuit board.
Turning clockwise increases the brightness, and vice versa. Please support the
circuit board with your hands during this in order not to damage it accidentally due
to excessive pressure.
17. Carefully install the housing of the railbus onto the chassis. It is recommended
to couple the railbus trailing car with another railbus with motor or with a different
locomotive and perform a break-in run at the full speed from 5 to 15 minutes in
both directions.
Important: To achieve best driving performance, please always keep the wheelsets
of the railbus and tracks clean from dust, fiber and grease.
Track 1
Track 2

Programming
This digital decoder is based on Doehler & Haass® hardware and software
technology. All functions and features are equal to those of Doehler & Haass®
FH05B multiprotocol function decoder. Programming samples shown below only
for DCC mode. For detailed information about all available features, as well as
programming in other modes (MM, SelecTRIX 1 and 2), please refer to the
complete programming manual available on Doehler & Haass official website:
https://doehler-haass.de
1. DCC Address: Default DCC address is 3. To change default address, desired value
(1-127) should be written to CV1. Long addresses (0001-9999) available; please
refer to the complete programming manual available on Doehler & Haass® official
website.
2. LED Brightness: The brightness of headlights, tail lights and interior lighting can
be adjusted. To change it, refer to the following table of decoder settings:
CV Function Range Default
52 Brightness of headlights at the both ends 0-31 31
54 Brightness of tail lights, cab 1 0-31 31
55 Brightness of tail lights, cab 2 0-31 31
N/A Brightness of interior lighting (analog) 10-100% 100%
3. Advanced light control: One of distinguishing features of this decoder is ability to
control all headlights and tail lights separately. It is useful when several railbuses
drive in consist. In this case, unnecessary lights between the cars can be turned off.
Default method to do this is to assign different DCC addresses to each of the
railbuses and switch off unnecessary lights on each car separately. It is also
possible to control all cars in consist using only one DCC address. Please see
complete programming manual available on Doehler & Haass® official website for
reference.
4. Decoder reset: The digital decoder comes already programmed; no additional
adjustments needed. To reset decoder to the factory defaults, write “8" to CV8.
After reset either a firmware update, the following settings should be restored for
correct functioning of the power buffer, motor and lights:
CV33 = 9, CV34 = 6, CV35 = 16, CV36 = 0, CV37 = 0, CV113 = 2, CV114 = 4,
CV115 = 2, CV116 = 4, CV137 = 2.

ATTENTION: This product is intended only for experienced users!
Please perform all operations with all precautions that apply to work
with ESD sensitive devices. The manufacturer is not responsible for
any damage to the train model and/or digital decoder caused by
improper installation, assembly or disassembly of the model, as well
as by exceeding the maximum allowed operating voltage.
IMPORTANT: Soldering work required for installation of this decoder.
Soldering station with adjustable temperature control, soldering iron with
thin tip (1-1.5 mm) and good soldering skills needed for this. Also, the
following tools required: M1 slot head screwdriver, small tweezers.
Digital Decoder
for Märklin Class VT 98 Rail Bus Trailing Car
User’s Manual
Ver 1.03
Art. No: ZDL-MRK-VT98-B
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Email: [email protected]
© Zmodell 2023
Made in Ukraine
Märklin® and SelecTRIX® are registered trademarks of Gebr. Märklin & Cie.
GmbH, Postfach 860, D-73008 Göppingen, Germany
Doehler & Haass® is a registered trademark of Doehler & Haass GmbH & Co.
KG, D-81249 Munich, Germany