In the 1950s Oral Roberts got a radio fixation. Actually in 1947, he founded the Oral Roberts Evangelistic Association and started making a whole a series of radio programs. There lies the problem. Which program or programs carried the radio quartet? Who were these four nameless singers? Were they ever really on the radio or were they session singers? According to the book The Life and times of Oral Roberts he got his first Gospel radio show in 1949. The book fails to mention call letters!
It's hard to find good information today as he fell (like many televangelists) in disgrace. It was the usual problems the $1000 suits, million dollar Palm Springs mansions, the diamond rings the personal jet. But he fell. By 2007, his evangelistic university in Tulsa needed a $70 million dollar bail out to escape creditors.