Welcome, golfknut
Here is your tvfool report as an active link
http://www.tvfool.com/?option=com_wr...e6a49e565724aa
The only difference I see is that KSWO ABC is a VHF channel.
Do you have trees in the signal path in that direction?
The only other thing I see is that you have a very strong FM transmitter only 0.5 mi away that is probably causing interference to ABC. You need an FM filter/trap.
http://www.fmfool.com/modeling/tmp/9...3/Radar-FM.png
We need more information.