Aww, that's too bad, because NBC is the network I watch the most, too... Law & Order, Law & Order: SVU, Law & Order: CI, The Office, Heroes, My Name is Earl, Studio 60, Dateline, etc. ...

I remembered that my old antenna was about 2.5 inches lower than this one is now, so I just lowered it 2.5 inches by taking it off its stand and putting it on a stack of books, and I'm getting a pretty steady 57% signal, and the wire is hanging off the back of my computer desk in a U-shape. This seems to work best for me when trying to get NBC, so I'll just use this wire-antenna location combination for NBC from now on.

Thanks for your advice. :)