Many thanks to Dave (N9EWO) who writes:
“I see a great You Tube file (it’s in 2 parts) of a WRNO Worldwide broadcast “off air” recording made on Dec 14, 1983.
Ah yes the memories[...] You can hear the very start of a Radio Earth program along with some on channel interference before (until they made the frequency change to 6185 khz) which was common.”
part1 (14:34) : http://www.youtube.com/watch?v=F4cQHkqntOU
part2 (5:44) : http://www.youtube.com/watch?v=5OaQunhtIAY