Well, wife switched channels to watch Jay Leno. I looked up from computer, and noted how unusually sharp the picture was. Wife agreed. I then moved closer to watch myself. It was a really clear picture, but in 4:3 without the light color side bars. I switched over to CBS HD to compare with Tonight Show. Wife and I both agreed NBC on 241 was about the same. So after watching Jay Leno a few more minutes, I decided to check the other national feeds I receive. However, only that one channel/show appeared to be in HD (or at least HD quality). After Jay Leno ended, the picture went back to normal SD appearance. I Posted this thread in hopes someone could explain what was going on. FYI, we were watching on our Loewe Aconda 38" CRT. That set does a good job even with SD feeds, but this was extraordinary for/if SD.