I'd throw some 1/4 sheets (2'x4') of plywood up there to help with footing to stand on in that area.
You see those METAL FOIL wrapped ducts? Well, those are going to play havoc with you being able to receive good solid signals up there. I wouldn't do it, BUT, if it's your only option, feel free to try it. You might get lucky.I tried to put in a full panoramic photo of the attic area, but the site said that was too big. Anyway, I opted for the Televes Dat Boss Mix LR Full band antenna. I did some measurements in the space shown, and I can just squeeze in the antenna without disturbing the duct work. It's a bit of a no man's land with no flooring, so I'd probably have to sit on those thin pieces of wood while assembling the whole thing, but it's the only usable space I have without having to crawl under all of the duct work.
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