HO 4-6-6-4 Challenger Locomotive with Tsunami2 DCC & Sound, UP #3823 (ATHG-1031)

This HO-scale Union Pacific Challenger locomotive reproduces ALCO’s iconic 4-6-6-4 design in the CSA-2 UP class, bringing a commanding UP-era presence to an HO layout. Equipped with a SoundTraxx Tsunami2 DCC sound decoder, it delivers authentic chuffs, whistles and bells for a lifelike run as it powers heavy freight—and, on some assignments, passenger trains—across UP routes such as the Wasatch grade from the 1940s onward.

On the rails, the model features illuminated number boards and headlights, tender-mounted sound with dual cube speakers, and current pickup on all wheels for steady operation. Pivoting front and rear engines help negotiate curves, with a minimum recommended radius of 22 inches. It runs on both DC and DCC, offers full DCC function support, and supports NMRA-compatible operation with CV-based tuning (a CV chart is included) for precise slow-speed control and easy multi-unit lashups.