Don, I've been reading and studying the literature and also experimenting. Book says that the A-B line automatically gets extended .6 miles from both the A and B. It seems to work that way for me - so far.

I agree on the piano player skills for boom switches, although I finally got around to fixing mine so they're lots easier. Sprayer came equipped with ball valves for boom control. Valves were controlled with dash mounted switches. When I mounted the Raven controller, I didn't hook the controller switches to the valves because the Raven switches are just ON-OFF and the Coupe switches change polarity of the control wires going to the valves in order to open and close them. As a temporary fix (8 years ago  ), I just manually flipped sprayer and controller switches at the same time. Last week, I mounted a gang of relays to replace the sprayer switches with just the ones on the controller. That should greatly simplify the piano player skills necessary to control the booms and keep the Raven properly informed about what's on and off.