LOS ANGELES – SEPTEMBER 3: A sideline official wears a vest with the logo for the Pac 12 conference during the game between the Minnesota Golden Gophers and the USC Trojans at the Los Angeles Memorial Coliseum on September 3, 2011 in Los Angeles, California. USC won 19-17. (Photo by Stephen Dunn/Getty Images)

The rise, fall and maintenance of regional sports networks