The automated type (9xx series) SOUND SYSTEM's were designed for the model railroader utilizing magnetic trips of the Horn and Bell. Each activation of the Horn triggers a different prototypical play pattern of the Horn. The Bell activates by a magnet tripping the Bell on and then off. This system can operate from track power and/or battery power. It will automatically adjust the diesel prime mover rpm with changes in track or motor voltage. Sounds produced are appropriate for the type unit listed. These systems can be mounted in the engine or car. They can also be utilized in a stationary mode with the Horn and Bell being triggered by either the train carrying a magnet or other momentary switch input. The sound systems are packaged with two reed switches. Appropriate speakers can be found on the 'Speaker' page. All of these sound systems have the same physical appearance as the standard DCv3 sound system shown at the top of the page.