WNBK-TV 3 was established as a Solid NBC-Owned operation by the mid-1950's, but apparently NBC wanted out. They coveted an owned and operated station in Philadelphia, which would give them the 4th largest market as an O&O..plus give them a solid string of owned stations in New York, Philadelphia and Washington. NBC convinced Westinghouse-owned WPTZ-TV 3 to move their operation to Cleveland while WNBK took over the Westinghouse Philadelphia facility. Westinghouse had built WBZ-TV 4 in Boston as their first TV station in 1948, buying WPTZ-3 in 1952 from Philco. They bought KPIX-5 San Francisco from Associated Broadcasters and WDTV-2 in Pittsburgh. from DuMont in 1954. (Renamed KDKA-TV) The Sale of WDTV effectively put DuMont out of the TV Network business.
The whole NBC-Westinghouse transaction consisted of:
Channel 3 Cleveland (Renamed KYW-TV)
AM 1100 (KYW Radio)
FM 105.7 (KYW-FM)
Channel 3 Philadelphia (renamed WRCV)
AM 1060 (WRCV Radio)
The transaction was completed by early 1956. Monday February 13, 1956 WNBK's final broadcast was a 11:45 AM special program..sort of a "changing of the guard." KYW-3's first official telecast was the Tennessee Ernie Ford Show at noon. There was also a parade and balloons and fireworks in downtown Cleveland that night in celebration though behind the scenes Westinghouse was'nt happy as we will see later. The programming was much more locally centered with several personalities coming to the forefront during the Westinghouse years..
Edit: I had originally forgotten about WBZ-Tv 4 in Boston..Thanks to Joseph Gallant for correcting me...