Jim randolph rose to fame in the 1950s and became an Los Angeles staple by the sixties. There are precious few airchecks of the man and his cuyrrent whereabouts are unknown.
He helped break the careers of R&B artists like Booker T & The MG, Larry Bright, and KoKo Taylor. This clip is from KGFJ, but he was also on WYNR and others. the was a "Big" Jim Randolph at KNOK in 1956, but I can't verify it's the same dude. KGFJ was progressive for it's day having an integrated staff. Their staff included other legends like Magnificent Montague, Johnny Magnus, Herman Griffith, Jim Wood, and Hunter Hancock.