LDT LS-DEC-NS-F Light-Signal Decoder Instruction Manual
- June 3, 2024
- LDT
Table of Contents
Littfinski DatenTechnik (LDT)
Operating Instruction
LS-DEC-NS-F Light-Signal Decoder
Light-Signal Decoder
for light-signals with LED
from the Digital-Professional-Series !
LS-DEC-NS-F Part-No.: 515012
> > finished module <<
Suitable for the digital systems:
Märklin-Motorola and DCC
For digital control of:
⇒ up to four 3-aspect signals of the Nederlandse Spoorwegen (NS).
⇒ speed sign is illuminated by slow speed.
⇒ realistic switching from stop (red) via slow speed (yellow) to proceed
(green).
Realistic operation of the signal aspects by implemented dimming function and
dark phase between the switching of the signal aspects.
This product is not a toy! Not suitable for children under 14 years of age!
The kit contains small parts, which should be kept away from children under 3!
Improper use will imply danger of injuring due to sharp edges and tips! Please
store this instruction carefully.
Label: blue point or NS
Introduction/Safety instruction:
You have purchased the Light-Signal Decoder LS-DEC-NS for your model railway
as a kit or as finished module.
The LS-DEC is a high quality product that is supplied within the Digital
Professional-Series of Littfinski DatenTechnik (LDT).
We are wishing you having a good time using this product.
The Light-Signal Decoder LS-DEC of the Digital-Professional-Series can be
easily operated on your digital model railway.
By using a connector plug bridge you can choose if you want to connect the
decoder to a Märklin-Motorola system or to a digital system with DCC standard.
The finished module comes with 24 month warranty.
- Please read the following instructions carefully. Warranty will expire due to damages caused by disregarding the operating instructions. LDT will also not be liable for any consequential damages caused by improper use or installation.
- Also, note that electronic semiconductors are very sensitive to electrostatic discharges and can be destroyed by them. Therefore, discharge yourself before touching the modules on a grounded metal surface (e.g. heater, water pipe or protective earth connection) or work on a grounded electrostatic protection mat or with a wrist strap for electrostatic protection.
- We designed our devices for indoor use only.
Connecting the decoder to your digital model railway layout:
• Attention: Before starting the installation-work switch off the layout
voltage supply (switch-off the transformers or disconnect the main supply).
The Light-Signal Decoder LS-DEC is suitable for the DCC data format as used
e.g. by Lenz-Digital Plus, Roco-Digital (switching via
Keyboard or multiMAUS only; switching via Lokmaus 2® and R3® is not possible),
Zimo, LGB-Digital, Intellibox, TWIN-CENTER, DiCoStation, ECoS, EasyControl,
KeyCom-DC and Arnold-Digital / Märklin-Digital= whenever no connector plug
bridge is inserted in position J2.
The decoder is suitable for Märklin-Digital~ / Märklin Systems or Märklin-
Motorola (e.g. Control-Unit, Central Station, Intellibox, DiCoStation, ECoS,
EasyControl, KeyCom-MM) if you insert a connector plug bridge on J2.
The decoder receives the digital information via the clamp KL2.
Connect the clamp with a rail or even better connect the clamp to an own
digital main ring supply assuring the supply of digital information free from
any interference.
Please attend to the marking on clamp KL2. The colors ‘red’ and ‘brown’ next
to the clamp are usually used by Märklin-Motorola systems (e.g. Märklin-
Digital~ / Märklin Systems / Intellibox DiCoStation / EasyControl). 
Lenz-
Digital systems are using the letters ‘J’ and ‘K’.
In case you assemble the decoder to an Arnold-Digital (old)- or Märklin-
Digital= system, you have to connect ‘black’ to ‘K’ and ‘red’ to ‘J’.
The decoder receives the power supply via the two poles clamp KL1.
The voltage shall be in a range of 14…18V~ (alternate voltage output of a
model rail road transformer).
If you do not want to supply voltage separately from a transformer to the LS-
DEC decoder you can shorten the clamp KL1 and KL2 with two wires. In this case
the decoder will get the power supply completely from the digital network.
Connecting the signals:
General:
Up to 4 signals can be connected to the Light-Signal Decoder LS-DEC.
Two signals per each 11poles clamp block. The build up of the two clamps is
identical. The following description refers mainly to one clamp only. As you
can see on the identical marking the description is also valid for the second
clamp.
Common connection:
All LED-signals of any manufacturer are designed in accordance to the same
principle. One wire of all light emitting diodes of a signal will be generally
connected to a common cable. Depending if all anodes or all cathodes are
connected together the signals will be called as common anodes- respectively
common cathodes-signal.
If you use signals with common anodes (e.g. supplied from Viessmann or
alphamodell) you have to clamp this cable to the connection marked ‘+’. In
addition you shall not insert the connection plug bridge in J1 in this case.
If you use signals with common cathodes you have to clamp this cable to the
connection marked ‘-‘. In addition you shall insert the connection plug bridge
in J1 in this case.
The second connection of each light diode is separated and mostly color marked
at the end and contains a series resistor.
Series resistor:
Light diodes have always to be operated with a suitable series resistor to
prevent that they will be destroyed. For this prevention all outputs have
already a series resistor of 330 Ohm integrated on the printed circuit board
of the Light-Signal Decoder LS-DEC. Is there no further external resistor the
diode-current will be about 10 mA.
This provides sufficient brightness.
For assigning the single cables of the light diodes to the correct clamp
connection please attend to the below signal images. The marks next to signal
light diodes are not corresponding to the actual light color but to the
marking of the connection at the Light-Signal Decoder LS-DEC.
If you do not know the correct allocation of the single wires to the light
emitting diodes you can test the function by connecting the wires to clamp RT1
or GE2. These outputs are active because the decoder switches all signals to
red after switching on.
3-aspect signal of the Nederlandse Spoorwegen (NS) with illuminated numeric
sign: 
2-aspect signal of the
Nederlandse Spoorwegen (NS):
Further sample connections are
available at the internet on our Web-Site (www.ldt-infocenter.com) at the section “Sample Connections”.
Additionally you can find detailed information about the Light-Signal Decoder
LS-DEC-NS at our Web site within the section “Digital Compendium”.
Programming the decoder address:
-
The jumper J3 has to be inserted for the programming of the decoder addresses.
-
Switch on the power supply of your model rail way.
-
Activate the programming key S1.
-
At least two light emitting diodes on a signal connected to the left clamp block (on this decoder side is the programming key S1) will be automatically switched over every 1.5 seconds in a flashing mode. This indicates that the decoder is in the programming mode.
-
Press now one key of the fourfold address-group to be assigned to the left clamp block of the decoder. For programming the decoder address you can also release a turnout switch signal via a personal computer.
Remarks: The decoder addresses for magnet accessories also to be used for the signal-aspects are combined into groups of four.
The address 1 to 4 build the first group. The address 5 to 8 build the second group etc. Each clamp block of a LS-DEC decoder can be assigned to any of these groups. It does not matter which of the eight possible keys used for programming will be activated. The decoder stores always the complete group of keys. -
If the decoder has recognized the assignment correctly the connected light emitting diode will flash a little faster. Afterwards the flashing slows down to the initial 1.5 seconds again.
In case the decoder will not recognize the address it could be that the two digital information connections (clamp2) are wrong connected.
For testing this, switch off the power supply, exchange the connection on KL2 and start addressing again. -
Press now the programming key S1 again. At least two light emitting diodes connected to the right clamp block will flash now. Repeat the programming as described above.
-
Now press the programming key S1 a third time for leaving the programming mode. All signals will be automatically switched to
Signal switching:
The opposite sample connections show how the fourfold address group can be set
by use of 8 keys of the push button panel for setting the turnouts or signals.
Between each pair of keys are e.g. the addresses 1 to 4. The two keys red and
green for each address are assigned to the turnout position round or straight
respectively the corresponding signal aspect which is indicated above or below
key.
The actual address section is related to which fourfold address-group has been
selected during the programming.
If you use a remote control LH100 of Company Lenz Electronic then red will be
the minus key and green the plus key.
The draft regards to one respective clamp bar only. As both clamp bars are
built up identical you can connect 4 signals to one decoder.
If e.g. the first home signal stays on red you can switch with address 1 and
the key green the exit signal to proceed.
The light emitting diode marked with GN will now indicate this at the signal.
You can observe the switching of the signal aspects from stop (red) via slow
approach (yellow) to proceed (green) as usual for Nederlandse Spoorwegen
signals.
If you use signals with illuminated numerical signs this sign will be
illuminated together with the yellow light emitting diode for slow approach.
Accessory:
For easy assembly of the printed circuit board below your model rail road
base plate we offer a set of assembly material under the order identification:
MON-SET. Under LDT-01 you can purchase a low price durable suitable case for
the LS-DEC.
Attention:
The Light-Signal Decoder LS-DEC switches the signal aspect not just on and off
but is dimming the light emitting diodes realistic up and down. Even between
the signal aspects a short off-phase is provided. Further digital commands
received during this switch-over-time of about 0.4 seconds will not be taken
up from the decoder. Please take care that the switching-commands are not in a
to fast sequence. The impression is absolutely realistic if the switching is
considerable slow. If the jumper J3 will be removed after programming of the
decoder addresses the memory storage of the Light-Signal Decoder LS-DEC will
be protected against any alteration.
Made in Europe by
Littfinski DatenTechnik (LDT)
Bühler electronic GmbH
Ulmenstraße 43
15370 Fredersdorf / Germany
Phone: +49 (0) 33439 / 867-0
Internet: www.ldt-infocenter.com
Subject to technical changes and errors. © 09/2022 by LDT
Märklin and Motorola are registered trade marks.