I'm a little surprised by two things:
WOLO from Columbia but not WNOK
WSOC from Charlotte but not WBTV
I also noticed that about WOLO. At that time, both WNOK (now WLTX) and WOLO were fairly low-powered stations, indeed, once you got outside of Richland and Lexington counties, viewing preferences skewed towards Charleston, Florence, Charlotte, GSAA, and Augusta CBS and ABC affiliates, with WIS being, then as now, the 600-pound gorilla for NBC programming as well as SC news.
Newberry County was part of the GSAA market for a long time, ditto Saluda County and Augusta. WRT WSOC as opposed to WBTV, it might just have been one of those sweet-spot reception things at the head end of Greenwood's cable (as may have been the case with WOLO). WSPA enjoys a similar straight shot right into Watauga County NC, I picked them up with a single rabbit ear on a small B&W TV set in Blowing Rock. There was one year when, per Television Factbook (sometime in the 1970s), WSOC was even carried on cable in Harlan County KY and showed 5-24% viewership in that county. I'm assuming it was dropped due to an extremely dodgy signal, very often in the mountains, what channels you get depends on what side of the mountain you're on. Around that time, TVFB said that WCPO Cincinnati was carried on one of the Harlan County cable systems, I have to suspect that perhaps one of the cable operators said to another, "I've got this antenna cut for channel 9, I can't get a usable signal, here, see if
you can do anything with it on your tower". People in eastern Kentucky in analog days tended to be very forgiving of snowy signals, that far out in the cut, you pretty much had to be.
