If it's the cardless box like what I have for my bedroom, it will tune at least a basic lineup. No guide, though there is an onscreen channel scroll (no program info, just channel and station name.) They're okay for a secondary TV, like for a guest room/kids bedroom/workshop TV. They're pretty much made for those old CRTs.
Usually only a full-on cable box is capable of channel delete, and even then it sometimes varies depending on model and software interface. It's a crap shoot, IMO.All DTAs are bare bones devices solely designed to tune digital channels and convert them to an analog form for older TVs. That's about all they're good for. Anything beyond that is not in their design.
Well, you're kind of stuck, then.You need to pressure Comcast to look into improving the signal, but they really only respond to threats of defection to another provider, if that. Yes, I know it's not practical for you, but they don't need to know that part.Beyond that, you're left with what you got.
He wants more than OTA, so his alternatives short of renting/buying everything on blu-ray are going to be compressed no matter what. I was suggesting something he could view right now and compare to his current (and unsatisfactory) cable TV.
A sat dish needs line of sight to the satellites. Things like trees can block the signal, so something solid like resin or a barrel will also block it. It's a signal coming from space, after all. The alignment is pretty orientation sensitive as well.
If the dish can point to the satellites (usually south) and you can have that section uncovered, you can probably shield the rest of it so it's not an eyesore.
Would need to see pictures of where you intend to put it and...