Here's a link to the wiki on one of the first scifi shows back in the day.
Good writeup about this show, and also mentions the many others that were done in those very early years.
I had that ring for many, many years and can remember this show as being a 'must see' for me and my family at the time, along with Tom Corbett.
The guy who played Captain Video really wrecked his career by playing that part. I remember reading how hard it was for him to get a job after the show ran it's course. First case of stereotyping I ever heard of.
Tom Corbett, Space Cadet was a good show too. The books were better, but that's usually the case.