I wonder whether Lights Out was the earliest sf anthology TV show. The first four episodes were live broadcasts on New York’s WNBT-TV (NBC) starting on 3 Jun 1946. It was renewed by NBC for three seasons of national broadcast starting 26 Jul 1949, and I spotted at least two time-travel episodes. Some episodes have found their way to Youtube, although I watched “And Adam Beget” on Disk 5 of the Netflix offering. I haven’t yet listened to any of the earlier radio broadcasts.

The episode “And Adam Beget” came from a 1939 radio episode of Arch Oboler’s Plays, and it formed the basis for a 1953 Steve Ditko story, “A Hole in His Head,” in the Black Magic comic book.