If the program is not broadcast in HD then the picture can actually look worse.

The stations broadcasting them digitally helps some but the problem is the TV attempts to translate them into HD and interpolates the signal.

If you have ever copied an old VHS format tape into CD or DVD format you can see the "pixellation". Same thing happens to HD.

You can compensate for it, somewhat by changing the format on your set but it still will look fuzzy or somewhat out of focus.

The TV will clarify the signal but unfortunately the new technical standards don't jive with the old analog format. Kinda like playing tennis by ping-pong rules.