NixTrainz NTZ-501 | ScaleTrains Sound Conversion Kit - Decoder Buddy, Keep-Alive & Speaker | HO Scale

Turn your ScaleTrains diesel into a fully sound-equipped locomotive with the NixTrainz NTZ-501 conversion kit. This all-in-one HO scale package pairs the V5b Decoder Buddy motherboard with a Power Bridge III keep-alive and a Scale Sound Systems speaker, giving you flicker-free lights, uninterrupted sound over dirty track, and a clean, solder-light install. Just add your favorite 21-pin decoder and you're ready to run.

Looking for more HO DCC and sound gear? Browse our HO Track, Tools & Accessories and HO Trains & Track.

Note: A 21-pin sound decoder is required and is not included.

• Complete sound-conversion kit for ScaleTrains HO locomotives — plugs onto the factory light board footprint.
• V5b Decoder Buddy accepts any standard 21-pin (PLuX/NEM) sound decoder for a plug-and-play brain swap.
• Power Bridge III keep-alive with dual 1.0 Farad super capacitors keeps sound and lights running across dirty track and frogs.
• Includes a Scale Sound Systems Universal #1 speaker pre-mounted in an enclosure for rich, full-range audio.
• Pre-installed 1.0K LED resistors and included mounting adhesive make for a fast, tidy install.
• Scale: HO (1:87)

Which locomotives does this kit fit?
It's designed for ScaleTrains HO diesels including the EMD GP38-2, GP40, SD7 & 9, SD40-2, and SD45, plus GE Dash 8-40C, Dash 9, and ES/ET/GEVO/Tier 4 models.

Does it come with a decoder?
No. The kit provides the Decoder Buddy motherboard, keep-alive, and speaker. You supply any standard 21-pin sound decoder of your choice.

What does the Power Bridge III do?
It's a keep-alive circuit with two 1.0 Farad super capacitors that stores power to prevent sound dropouts, light flicker, and stalling on dirty track or turnouts.

Do I need to solder?
Installation is largely plug-and-play thanks to the 21-pin Decoder Buddy, though basic hobby soldering skills are helpful for the speaker and keep-alive connections.