I was stationed JE1BQE in 1971, and JA9QZH in 1976. There were many HAM Radio Operators to enjoy 6m Band in the 1970's, who were junior high school or high school students. I used to enjoy talking with them when I was a boy, too.
My licence in 1970's was Amateur 2nd-Class Radio Operator, Output power limit is 50 watts, that there was no difference between Amateur 1st-Class Radio Operator and Amateur 2nd-Class Radio Operator.
I upgraded my license to 1st Class in 1983. Recently, the output power limit is 1000 watts for Amateur 1st-Class Radio Operator, and is 200 watts for Amateur 2nd-Class Radio Operator.
I am an active member of SMIRK (Six Meter International Radio Klub).