On this page, you find information about:

  • how to build a German dwarf light signal with LEGO bricks,
  • equipping the it with lights,
  • automating the signal with a MattzoLayoutController.
Light dwarf signal showing Sh0
Light dwarf signal showing Sh0

About the signal

The signal was originally designed by Matthias Runte of MattzoBricks in 2021. Julius Brönner contributed some valueable ideas and details in 2023.

The signal indicates that the track ahead is blocked or cleared for shunting operations.

German dwarf signal showing Sh0


The signal can show two different aspects

Sh0 – Stop

The Sh0 aspect is indicated by two red lights. Vehicles may not pass the signal

Light dwarf signal showing Sh0
Light dwarf signal showing Sh0

Sh1 – Clear

The Sh1 aspect is indicated with two diagonal lights. The vehicle may pass for shunting operations.

Light dwarf signal showing Sh1
Light dwarf signal showing Sh1

Shunting clearance

Two white digital lights indicate the “shunting clearance”. This means that the train main enter the shunting area, but has no clearance to operate on the following main track.

How to build the signal

(this section will be added shortly)

Required Parts

The signal can be built with standard LEGO parts and some extra parts as described below. No printed parts are required for this signal.

Additional parts are:

  • LEDs (3mm) in white and red colour.
  • Thin copper wire with black lace to power up the LEDs (diameter 0,15 mm).
  • Basic stuff like a wire board, cables, plugs and connectors.


To equip the signal with lights, I have used 3mm LEDs in different colours. The wires are very thin, black copper wires used for model scale train layouts. The wires are led from the top of the signal through a pipe on the backside of the signal post. To prevent the LEDs from burning off and to save electrical power, you can add some resistors to limit the current through the LED. At a voltage of 3,3V, 120 Ohm should usually be a good value. Red LEDs usually require larger resistors than others. In question read the data sheet of your LEDs.


The signal is automated with a MattzoLayoutController (MLC). The MLC receives commands from Rocrail and lights up the correct LEDs for the current signal aspect.

Find more details about the MLC here.

To use the MLC with signals is described here.



Julius Brönner contributed some details to the design of the signal.

Thank you for your contribution, Julius.

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