(c)1990 WGNT-CBS Corp.
(c)1988-92 Warner Bros. (program)
WGNT promo for the 1988-92 syndicated series "Superboy", which apparently focused on a younger Clark Kent (looks like Dean Cain, but I think there may be more a general "Superman" look the casting department looked for as Gerard Christopher played him by this point, replacing John Haynes Newton). The show was reportedly axed by WB management in 1992, presumably because they didn't want a second Superman series running when they were getting ready to launch the 1993-97 ABC variant (Lois and Clark).
Also notice that there's a "TV With a Bang" caption over the logo at the end. In the first "post-Pat Robertson" years, WGNT would sometimes do this with their promos.