Is it true that the voice on the radio on Gilligan's Island is the late legendary Chick Hearn, Los Angeles Lakers announcer ?

Most of the time the voice on the radio was the voice of Charles Maxwell. BUT Chick Hearn was in two episodes of Gilligan's Island as a voice on the radio. He was in the episodes "It's A Bird, It's A Plane, It's Gilligan" and "Splashdown." I checked the Internet Movie Database and, yep, it's him. :)