I cannot get hd channels on my hitachi 51f510 tv.

SOURCE: Hitachi 51F510

I replaced the screen on my 62 inch big screen for about $50 and the picture is very good! You simply need to purchase a piece of plexiglass from a glass shop or hardware store and have it cut to the EXACT dimensions you require for your TV. NEXT the plexiglass must be FROSTED. This can be done by a fine particle sandblaster or power sander with a fine grade paper. I used a power sander and sanded BOTH sides methodically and vertically on BOTH sides. I recommend buying a couple of 12 inch wide strips to test which method pleases you most by placing them in the path of the projected image where the old screen was removed. In any event, I recommend frosting BOTH sides.

SOURCE: Red Tint on Hitachi 51F510

sounds like image burn,try it on normal viewing size and see if its still there and in the same area if so image burn on crt from the 4:3 aspect mode .

SOURCE: Hitachi 51F510 51 in. rear

Maybe you need new batteries a-hole

SOURCE: Color Problems with Hitachi projection screen television

check the bulbs

SOURCE: PROBLEM WITH GETTING LOCAL hd CHANNELS

You need to have a set top box.

By law, as of March 1, 2007, almost all televisions should include a built-in tuner (called HDTV, digital, or ATSC tuners) that can receive high-definition programs over the air by simply connecting an antenna. Your HDTV doesn't have such a tuner, you'll need to connect an external tuner (or cable or satellite box) to watch high-definition programming. External over-the-air HDTV tuners currently cost at least $150.