I have an 4:3 HS420 and my parents have one of the last monster sized 4:3 XBRs with a superfine pitched tube. Viewing 16:9 HD material with this sets is great, but the options for viewing 4:3 programming delivered via a 16:9 HD signal downright stinks on these sets. In order to get the 4:3 picture to fill the screen I have two options.

1. Set the HD STB to output a 480p signal. The TV will scan the full surface of the screen. Use the aspect feature of the STB, to switch back an forth between 4:3 and 16:9. This method works best for watching 4:3, but the 16:9 HD material will be at a reduced resolution (not very noticable with a HS420). Technically it would be EDTV and not HDTV. However, my parents can't do with their XBR because they use the internal cable card tuner.

2. Set the HD STB to output a 1080i signal. The TV will scan only a 16:9 portion of the screen. Use the internal zoom feature of the TV to switch between 4:3 and 16:9. 16:9 will look the best and be at full resolution. The zoom feature of the tv will allow 4:3 material to fill the entire screen.

HOWEVER.... The 4:3 picture quality is unacceptable. There are numerous digital artifacts, and greatly reduced color. It is like watching a VHS tape. The scaler appears to operate at less than NTSC resolution. Worse yet the set zooms in too much and cuts off material within the safe area. Because of this my parents watch 4:3 material with the TV in 16:9 mode resulting in a letterboxed and pillar boxed image which drives me nuts.

Has anyone found a solution for this problem? Such as.... An HDTV tuner that will automatically switch between 480p in 4:3 aspect for zoomed in HD, and native 1080i/720p for full 16:9. I can do this manually with my STB, but it involves fliping a switch in the back of the box and changing the aspect ratio in the menu.

Are there any service menu options that will make the set's internal zoom feature acceptable in picture quality?

You really should also consider getting an s-video cable and use that between your STB and one of the video inputs (probably need set of stereo audio cables to match the video input also).

Switch the input instead of using the zoom - the picture will be better. Alternately or additionally tune the analog channel equivalent to the HD channel when viewing 4:3 on an HD channel.

The ATSC committee recognizes the need for putting aspect ratio information in the signal - but action on that is a ways off and designed more to appease the 16:9 masses rather than avoid a postage stamp on a 4:3 HDTV. Anyway you would need a smart box to implement the signal info when available years from now.

Another alternative (at least for me) is to add the SD digital channel equivalent if its available (eg add the HD ABC channel and SD ABC channel to your favorite lineup)

I don't know about service menu adjustments to zoom other than size