Patrick, thank you! I was so sure that there was something wrong on the signal side of things I completely ignored the obvious- to make sure that there was good power to the chip. DOH! After reading your last post, and doing a quick check, I found that my soldering job on pin 7 was bad, and the chip was not getting power. A little heat, a little more solder, and I now have a 100% working tuner (and some experience).

Thanks again for all of your efforts and additional insight into what makes this thing work. I'm guessing that at least one other person with similar problems will find all of this helpful.

Cheers,
-Randy