On November 23 1947, NBC did away with the historic call letters for its San Francisco flagship station. KPO became KNBC.
The station continued to broadcast NBC network programming as well as locally-originated programs.
In 1949, a major construction project saw a new 550-foot tower installed at KNBC’s Belmont transmitter site. The project was designed to improve the station’s evening and nighttime signal, and station management would report a roughly 10,000 square mile increase in KNBC’s prime coverage area.
KNBC’s San Francisco era ended in 1962, when NBC designed to move the KNBC call letters to its television station in Los Angeles, which had been known as KRCA (Channel 4).
NBC had requested a reinstatement of the original KPO call letters but the Federal Communications Commission rejected the request.