Color me impressed by today's puzzle. There are a remarkable six full theme entries, including the revealer, BACKCHANNEL. Perhaps "back channels" is more recognizable, but I think this version is definitely acceptable. And what a clever thing to find five different television or cable channel abbreviations hidden in the long answers today! Of course I like WAXONWAXOFF best, but its hidden channel the least.
You have to admire all of that theme material, and also being able to work in REDASABEET and BOBBYRIGGS. The latter amused me because not only did he lose the "Battle of the Sexes," but he's crossing over 35A: Portia de Rossi, to Ellen Degeneres (WIFE) and a sports BRA, showing how clearly his particular brand of chauvinism has lost out over the years.
In any case, I won't FRET over less than thrilling answers like ASEC, MGMT, or the peculiar plural ANNS. When the theme material comes as thick as it does in this puzzle, you have to accept some glue.
My favorite clue came at 5D: B+, e.g. (ION). I could certainly niggle a little with it, in that Boron's ion would be B+3. But the clue is certainly clever.
I found this puzzle more difficult than a typical Tuesday. Part of it was a peculiar tendency to make typos. I couldn't remember if POTSIE had an S or a Z. I tried ZIPperlok (?!) at first. In any case, all's well that ends well.