Søren's Model Railway Pages

About model railways in H0


Testing the Märklin mLD decoder

A model train

A few months back I bought a class 141 from the Trix range. I needed this locomotive for my pool of regional locomotives, which are currently dominated by class 111.

The Trix locomotives has 21-pin decoder plugs, so I needed a decoder for this purpose. I earlier had problems with installing LokPilot 21-pin decoders in Trix TRAXX locomotives (classes 185.2 and 146.2). The reason being that the headlight controls on the Trix TRAXX is located on AUX 3 and AUX 4. The LokPilot does not support this configuration. If you are not into modifying the locomotive motherboard, at that time, you had no other option than to use the Trix DCC decoder. I had no idea on who made that decoder and found it to be quite limited in what it could do, so I modified the motherboard to work with the LokPilot.

The new Märklin decoder family is a quite different story from ealier Märklin/Trix decoders. It is now fully DCC compatible and have a load full of options, all in all it looks like a quite competent decoder. So I thought I would give the new Märklin decoder family a try with my class 141.

Note: Trix has changed the light configuration on the class 141 to use AUX 1 and AUX 2 and not AUX 3 and AUX 4 as with the TRAXX class. This means that you actually can use a 21-pin LokPilot without modifying the motherboard.

The Packages

The Märklin decoder family has two main decoders

  • mLD - Märklin Locomotive Decoder
  • mSD - Märklin Sound Decoder

The decoder comes in a variety of different kits, as that may seem overwhelming, there is actually just one decoder. The many kits are different retrofit kits, that will help you retrofit almost any Märklin or Trix locomotive - or locomotive of any other brand that is - to use the mLD or mSD.

A model train

The sound decoder comes in special configurations for the Hobby locomotives (classes 185.1, 185.2, 146.1, 146.2, ER 20, ÖBB 2016 and 232, 234). You can buy a set with either electro locomotive sound (class 185) or diesel engine sound (class ER 20, Hercules). The sound decoder contains replacement motherboards for the Hobby locomotives. Replacing the motherboard and built-in decoder will greatly improve the performance of the locomotive.

There are also sound decoders to build into other locomotives. Again preconfigured with sound for steam, diesel or electric locomotives.

Last but not least, there is a standard 8-pin plug edition of the mLD as well as a 21-pin version. This article will cover the 21-pin mLD (60942).

The mLD package (60942) contains:

  • The mLD 21-pin decoder
  • A 21-pin adapter board with cables to install in the locomotive (should it not have one)
  • A plastic mount for the adapter
  • A screw

Tip: The Märklin Central Station 2 will allow you to replace the built-in sound schemes with sounds schemes from the Märklin website. Märklin is building a comprehensive library of sound schemes, so you can find a sound scheme that will fit your locomotive class. The Märklin Central Station 2 will also allow you to update the decoder firmware. If you do not have a Märklin Central Station 2, your dealer should be able to help you as well.

The Specifications

The manual specifies the features as follows.

Continuous current load at the motor output  <= 1.1 amps
Current load at the light outputs  <= 250 milliamps
Current load at AUX 1 to AUX 4 each  <= 250 milliamps
Current load at AUX + lights (total)  <= 300 milliamps
Current load for motor and AUX 5 to AUX 6  <= 1.1 amps
Maximum total load  <= 1.6 amps
Maximum voltage  <= 40 volts
Sound performance (at 4 ohms / 8 ohms) 2.3 watts / 1.2 watts

Short circuit and overload protection at the outputs lights front (LV), lights rear (LH), AUX 1 to AUX 4 and at the motor outputs. If you need a function decoder instead of a locomotive decoder, you can configure the decoder to use the motor output as two additional function outputs (AUX 5 and AUX 6).

The Verdict

With the mLD and mSD family Märklin has finally come clean an provided a good allround decoder that will work with almost any locomotive. Since Märklin now talks DCC, there is no problem for you to use the mLD or mSD on your 2-rail layout. I will be using mLD in all my 21-pin locomotives, which is not that many, but I will no longer worry about what decoder to put in them.

I have not tried the 8-pin version, but I will at some point.

The mLD are a bit more expensive than their ESU counterparts, but if you look for offers, I have seen them at around 22€ which is a very fair price.

If you have an 21-pin locomotive lying around needing a decoder, you should try out the mLD, I think you will be happy with the result.

Happy modelling!