With that antenna, you can just remove all of the metal elements and replace them with a pair of dipoles. It's easy. PM me about it.
Excellent analysis Mr 72! This is a really annoying issue for us Austinites and I think you have really nailed it. I live in South Austin (Slaughter/Manchaca) and have also gone through a series of antenna installations to try and resolve my reception issues. Same story here - I've got the 622 and a roof mounted DB2 with all my reception levels above 78 and Fox at 95 but with frequent drops. I don't want to attenuate everything because I easily lose KNVA 54 once it drops into the low 70's so the selective attenuation of KVUE seems to be the best solution. I don't mind constructing a custom antenna but I am not much of an RF engineer. Can you post a how-to for constructing your custom antenna tuned to UHF 22 & 49. I know it involves cutting and attaching metal elements tuned to specific frequencies but I would feel much more confident just following a guide written by someone who knew what the heck they were doing. I think this would help a bunch of us here in Austin.