For converting Märklin / Trix H0 locomotives with built-in high-performance motors or other DC motors. The märklin LokDecoder3 has a soldered-on cable harness with an eight-pin NEM interface plug for the individual retrofitting of many locomotives with a corresponding NEM interface and locomotives with a lack of space. The märklin LokDecoder3 supports the digital formats mfx, MM1, MM2 and DCC.