Athearn Genisis Big Boy DCC Sound Decoder PCB Board (HO Scale) Unboxed New athearnApril 18, 2026admin Athearn Genisis Big Boy DCC Sound Decoder PCB Board. This is Brand New and Sealed From the Athearn Factory. This it the replacement PCB for inside the tender. All payments must be in GBP (Pounds Sterling). Take a look at our other items.