We do not remember these from Saturday mornings... but a bit later on from morning cartoons (then in syndication) before school of a day... (Note: often and up till the mid 70's , Te Knight was a often used voice ... especially on Batman)
I don't think I ever got to see these until the internet came along. Super Friends really eclipsed these for a long time.
That was Ted Knight ( "Ted Baxter of Mary Tyler Moore Show)
Meanwhile, at the Hall of Justice...