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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. What's Included Item Qty V5b Decoder Buddy (with 1.0K resistors) 1 Power Bridge III keep-alive (two 1.0 Farad super capacitors) 1 Scale Sound Systems Universal #1 speaker with enclosure 1 Mounting adhesive 1 Note: A 21-pin sound decoder is required and is not included. Features 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) More Information Brand NixTrainz Item Number NTZ-501 Scale HO (1:87) Product Type DCC Sound Conversion Kit Decoder Interface 21-pin (decoder sold separately) Condition New UPC 0494000024003 FAQ 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.
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🇺🇸 Ship from USA · On Agora since 2026
$49.99