You had to be really lucky to ever see this show because it only aired for about a year in the early 80's. While I am considerably older than I think most people on Steemit, i was only just old enough to be cognitively aware of what was going on during this thing.
It only happened on Saturday mornings and even then it was only for about 10 minutes as it was not even it's own show, it was simply an add-on to other cartoons.
I will admit that i was too young to really even know when this would air but it really wasn't important because cartoons were LIFE back in the early 80's and we would wake up at the damn crack of dawn in order to have a look.
Now, looking back, i can say that Thundarr was set in a post-apocalyptic future and while there were futuristic elements to it, for the most part everything was quite "manual" in that weapons were swords and arrows and what not.
It ended up not being popular enough to carry one beyond the 2 seasons that the story encompassed but would later be re-released a few years later in 1983. This was a precurser to He-Man, which as I am sure you are aware went on to be exceptionally popular.
I'm definitely dating myself by revealing that I really liked this show, even though i was probably still young enough to be pooping my pants on a regular basis at that time in my life. This show was just so epic, and while it never gained much fanfare, was likely my favorite show in my very early life.
I wonder if there were ever some comic books made about it. I would certainly like to get my hands on them if there were.