1. Eliminate the switch. Use 1 cable from receiver to LNBF (thru motor, but see below try without it)
2. Is it possible to not use the motor, try to set your dish fixed?
Reason I say that, it's easier to locate 1 satellite, get the feel how the
aiming works, how the software works in the receiver.
Use AMC3 to line up your fixed dish, it would be a good one, lots of
PBS type stations with strong signals.
These things are very touchy for a signal. 1/8" movment in the dish will lose the signal... i'm kinda tired right now to attempt to decipher your numbers, maybe someone else can pipe in on your calcucations...
Good luck.