I recalled THE TIME TUNNEL after watching the first episode of TIMELESS (2016), which seems basically like a remake.
Watching THE TIME TUNNEL during the summer vacation as a kid during the 80's was nothing less than a tradition. The good old days of series like THE TIME TUNNEL and THE PRISONER. Here in Israel viewers had to call the TV line and vote which series they want to watch that day, so I don't think I ever watched any series completely or in sequence.
Anyway, in Episode 4 Doug and Tony are traveling in time to 1941, just before the Pearl Harbor attack. Tony meets his younger self and his father who died in the attack.
Admittedly, the series shows its age. The episode is a bit slow and acting is a bit wooden. But all in all, it was and still is a great series and gives a fuzzy feeling of nostalgia. Although made in the 60's, for me it takes me back to the 80's and brings very strong memories. Good score, too.
I think that one of the key differences between TIMELESS and THE TIME TUNNEL is that in the former they can change history events, while in the latter they can't (IIRC).