I am more than a little concerned about your method. Especially with DirecTV, the dish alignment on the Ka birds needs to be extremely precise. Using the very course and slow to update meters built into the receiver, is like trying to cut the steak on your plate with a hatchet. It can be done but the end result isn't always pretty.

I have seen many people complain about loosing signal with the slightest rain, when the dish was not peaked out as well as it could be.