NBS (Philippine TV network)

DZNB-TV, Channel 4, is the flagship VHF station of the Philippine television network, NBS. The station is owned and operated by NBS Pilipinas Inc. with its studio and transmitter located at the NBS Broadcast Complex, Samar Avenue, Diliman, Quezon City. It is the first and oldest television station in the Philippines, operating 24 hours a day. It serves as the originating channel of the network's national television programming which is broadcast to all its regional stations.

History
DZNB-TV traces its history to the first Philippine television station DZSV-TV, owned by Montecarlo Electronics Corporation and later renamed as Montecarlo Media Company.

Severino Montecarlo Jr., owner of MMC, was first to apply for a license to establish a TV station in 1941. But due to the war, his request was refiled on August 7, 1946 and was granted on November 19. Because of the strict import controls and the lack of raw materials needed to open a TV station during those days, Salvacion branched to radio broadcasting instead.

DZSV-TV began commercial television operations on March 12, 1949, the first fully licensed commercial television station in the Philippines. After the premiere telecast, the station followed a six-hour-a-day schedule, from four in the afternoon to ten in the evening.

The first program broadcast at 4:00 PHT during the then-called broadcast commencement exercises, with the playing of the national anthem of the Philippines "Lupang Hinirang", followed by an announcement of that day's programs and the commencement of MMC television programming.

In 1954, Cabanatuan Electronics Corporation owner Manolo Villarosa Sr. and Eduardo Villarosa acquired a radio-TV franchise from Congress and immediately established Villarosa Broadcasting Company (VBC) on July 18, 1954. On October 10, 1957, VBC was bought. The corporate name was changed to National Broadcasting System immediately after the purchase of VBC.

With the establishment of DZEB-TV 10 of MBS in 1955, the Montecarlos controlled both television channels in the archipelago, and plans were underway to build a new headquarters for the network in Samar Avenue in Quezon City, which was officially opened at the same year, and later became the official studios for Channels 4 and 10. The monopoly in television was broken the same year when DCBS-TV 3 and DNBC-TV 9 was established by their respective owners. By 1957, with the official launch of its first ever regional station in Cebu, the NBS brand was officially used for the first time on the station in newspaper ads promoting the first ever locally produced television dramas.

Channel 2 and 10 started test color broadcasts in 1959.

In 1962, NBS became the first TV station to broadcast selected shows in color and by 1963, the company was renamed NBS Media Corporation. This company became the formal merger of the two stations DMMC-TV 4 (MMC) and DVBC-TV 10 (VBC) and were both named NBS, only separated by 1 and 2 to avoid confusion.

On November 11, 1965, NBS opened its present-day Broadcast Center complex in Bohol Avenue, Quezon City; it was then the second most advanced broadcasting facility of its kind during its time in Asia after NHK in Japan and ABS-CBN also in the Philippines in 1967.

On March 12, 1969, on its 20th anniversary, its sister station DVBC-TV transferred to channel 12 (now occupied by SIDtv). This was in response to frequency adjustments, as the television station of the EMedia was launched and occupied the Channel 10 frequency.

Digital channels
UHF Channel 23 (527.143 MHz)