I have 3 dishes (2 motorized) and 4 LNB's.
One dish is a big 12 ft. dish with a
BSC621-2. I don't use the built in
diseqc switch on the BSC621-2, but rather I have run two coax cables back to my diseqc switch.
So I am using just one diseqc switch...
LNB 1 goes to C on the big dish.
LNB 2 goes to Ku on the big dish.
LNB 3 goes to Ku on a fixed dish.
LNB 4 goes to Ku on a small motorized dish which has a 36 volt HH positioner.
I use a separate old receiver to move the small HH dish and this receiver has no connection to the LNB on that dish - just connected to the positioner.
So to use the 2nd dish with a positioner, I just specify in set-up (main receiver) to use LNB 4 and positioner off. Then use my old receiver to move the dish to the correct satellite.
But basically the fixed dish is pointed at my most used satellite. And the 2nd motorized dish is left pointed at another most used satellite. So I don't typically have any need to move the 2nd motorized dish. But can if I need to.
So far as using an A/B switch, there are
remote control A/B switches, but I don't know if these would work OK with the high frequencies used for a satellite coax connection? I have read that the more connections you have, the more signal loss you have.
I know if I have a splice/connection in my coax cable and use a regular "hardware store" coax connector, I will get a lower quality and signal strength than if I use a "high frequency" rated (blue colored) connector.