Yes. The bandwidth is limited. The specs are designed for one HD subchannel with the others in SD.

In Chicago, both PBS stations do a lot of simulcasting on an SD subchannel.
It comes in handy sometimes to avoid transcoding.

Right, like I said, sub-channels are probably SD (although I have to admit I've never recorded one, I should try and see).

The problem is, not every channel offers an SD version of what they're showing on their main HD channel. In our area, of the big 4 networks, the NBC and CBS affiliate show weather on their SD subchannel, the ABC affiliate has two subchannels and shows weather and 70's TV shows (!), and Fox doesn't have a subchannel at all.

So that's fine if you want to record local weather or Magnum P.I., but not so much if you want to record anything else.

I've got an HD-5500 that I am happy with.

You really don't want to do transcodes on a slow box...

A digital converter box does actually sound like exactly what you need. They are controlled with IR remotes, just line cable and satellite set tup boxes. It should be no more difficult to get one working that a cable or sat stb. The Apex DT250 is the model I am interested in.

The US govt is giving out set top box coupons to help ease the transition to digital for those of us not buying a new TV.