You can trigger the bell and whistle/horn sounds in your LGB 6500x Sound Unit with this easy-to-install kit. It's engineered to fit most LGB Mogul locos and LGB rolling stock with "Archbar" style trucks (LGB 67402 as found on cars like the 43620, 43670 and 48720). Just attach the trigger to the truck with the included screws and plug the connecting cable into your sound unit. Use with LGB 17050 Sound Trigger Magnets.
This kit can be easily adapted to other locos and styles of trucks. However, factory support for other applications is not available. On MTS layouts, the bell and whistle sounds can be triggered remotely, and this kit is not necessary.