NBC launched the NBC News and Information Service (NIS) in 1975.  It allowed local radio stations to launch all-news formats, providing affiliates with up to 55 minutes of news per hour. 

NBC aired the service on its Washington station, WRC.  It also added the all-news format on its network-owned FM stations in New York City, Chicago and San Francisco.  

Many stations signed on with the service, but by 1976, NBC was not sure if its network would ever become profitable.  Affiliates got a six-month notice that the service would end.  NIS closed in 1977.

Here’s a link to an NBC NIS sales booklet.

Source: Wikipedia (NBC)