Conversation so far:
When did Johnny Carson first get on the internet?
When did Johnny Carson first get on the radio?
Johnny Carson began his broadcasting career in 1950 at WOW radio and television in Omaha.
What was Johnny Carson's first radio show called?
Johnny Carson hosted a morning television program called The Squirrel's Nest.
Was Johnny Carson's morning television program The Squirrel's Nest successful?

Question: did he leave abc
Self-contained rewrite: Did Johnny Carson leave American Broadcasting Company?