Off air HDTV - Pixelization

Is getting pixelization (ie - temporary freezing) common while using an off air antenna? Is this the antenna capability? Or could it by my receiver (DirecTV HD TiVo)? Would I have better luck plugging the antenna directly into my TV (Sony KDLV40XBR1)?

Most of the time it is an annoyance. But sometimes it happens so often that I have to revert to the standard def station.

Thanks, John

All of the links in the chain can have an effect on the strength of a signal. But, all things being equal, my guess is that signal isn't coming on a straight line or that something is interfering with it. Change of location or direction of the antenna might help.

Analog transmission has an advantage over a digital one; no matter how weak it may be, something of it will survive the journey to your screen, even if it looks like hell when it gets there. Digital transmission has an all or nothing quality about it. Below a certain level, it cuts out altogether or pixellates unbearably. If the interference is temporary and chronic, it'll just come back as if nothing ever happened. A digital picture can also be a victim of multipath, a phenomenon in which the signal deflects and divides because of various obstacles, thus cancelling it out at your display.

Tuners and antennas stand or fall on how well they handle such potential difficulties, but often reorienting or relocated the antenna can help. A rotor near the TV that lets you change the antenna's direction while you check the picture is often a lifesaver. You can mark the best spot for each channel on the rotor itself. You can get a rotor at Radio Shack. Hopefully, that'll be all you need. If not, troubleshooting could be a pain in the neck.