Test Setup Every now and then I'm at shows running trains with the HOm swiss narrow gauge group of the ETE San Francisco Bay chapter . The operating scheme is straight-forward: The layout is set up with a single track main line, a couple intermediate stations, and staging at each end of the layout. The typical setup consists of staging with a return loop at one end, two intermediate stations, and a simple staging yard at the other end. Operators are positioned at the stations or staging yards and verbally hand-off trains from station to station. A typical conversation between two neighboring stations goes like this: - "Can I send you another train?" - "Yes, go ahead. Once that's here, I'll send you a train back." - "Ok." This works quite well. However, problems arise at shows with lots of visitors since the noise level makes communication, or even getting the attention of the other operator, difficult. Especially when the layout is arranged...