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LGB 55029 Decoder introduction:

The  LGB 55029 decoder is suitable for use in digital operation (DCC, mfx) as well as in analogue operation (DC). 

All LGB  traction vehicles built from 2014 onward can be converted with the 27-pin interface. 

Many vehicles with the old 10-pin interface can be converted using the 55529 interface adapter. 

Vehicles without an interface can be converted using the included interface board, as supplied as part of the Retrofit package.

A loudspeaker is also included, but other loudspeakers that match the impedance value ​​can also be connected.

Compared to the previous LGB 55028 decoder, the performance has been increased significantly, and it also offers significantly more functions and programming options. 

With the Märklin mdt3 Decoder Programming Software, the Marklin 60971 Programmer & a LGB 55129 Decoder Interface, the  decoder can be easily programmed and adapted to individual requirements. 

The extensive sound library can be downloaded, which has been expanded to include a large number of the well-known LGB models, which is updated regularly.

Load at the motor output < 4 Amps.

Load for the light outputs AUX 1 - 4 each 900 milliamps.

AUX 1(LV) + 2(LR) together max. 900 milliamps.

AUX 3 + 4 together max. 900 milliamps. 

Load AUX 5 - 6  each 1.75 Amps, together max 3.5 Amps.

Total Load 8.4 Amps.

Sound output at 4 Ohms 6.7 watts.

Locomotive address 1-10239 programmable.

14 or 28 (126) speed steps.

Analog and digital load control can be adapted to different locomotive types.

Parallel control for all light and function outputs.

 Programmable flashing light and short-term functions.


Acceleration and braking delay can be set separately from each other.
Alternative constant braking length.
Programming on Main (PoM), this programming must be supported by the controller. 
To do this, follow the operating instructions for your controller.
Adjustable switching range.
Braking / signal stopping section recognition in digital operation.
Especially fine motor control.
Automatic setting for the motor control with a Calibration Run.
Wide ranging function mapping. Independent combination of functions.

From the LGB 55029 decoder manual.
Note: The AUX outputs on the decoder are preset for the use of light bulbs (18 volts).
This figure may well be correct if using either a LGB 51095 or a Marklin MN 60101 power supply with an output of 19 V when connected a Marklin CS 3 Central Station.

When connected to the PIKO DCC System these and the SUSI outputs have an output voltage of 22.30 V, and connected to the Massoth DCC System of 21.40 volts.

CV's 113, 117, 121, 125, 129, 133, 137, and 141 which are the dimming CV's for the LR, LF and AUX 1 - 6 outputs are set to 255 based on the 18 V input, perhaps should be changed to a value of 198 to take into the account the higher voltage available from the PIKO 350000 and Massoth 1200T power supplies.

Upper and lower views of the decoder.

Definitions of the pins on connectors ST 1 and ST 2.

LGB 55029 Retrofit Sound and Control DCC mfx Decoder.

LGB 55529 Decoder Interface, additional Home Brew cable for connection to the 10 pin cable and direct to a motor block.