The station was always in the red and Stewart was about to give up, when the program "Dancetime with Chito" suddenly became an instant hit and advertising revenues started to pour in. Canned programs from the United States further sustained its success.
In 1972, PresidentFerdinand Marcos declared martial law in the Philippines and the station was forced to shut down, though it only lasted for more than 3 months, and returned on the air in late-December of that year; the station was blocktimed by the National Media Production Center (NMPC) with limited three-month permits.[3] In 1974, RBS, including its TV and radio stations, were sold to a triumvirate composed of Felipe Gozon, Gilberto Duavit Sr., and Menardo Jimenez who introduced a programming concept catering to the new audience. The new management acquired new equipment and introduced new programs and a new name, GMA (Greater Manila Area) Radio-Television Arts with its new identity, "Where You Belong" in 1978.
In 1983, DZBB-TV broadcast the funeral of Senator Ninoy Aquino. At that time, it was a small item due to immediate censorship. But, the station bravely broadcast the coverage with a limit of 10 seconds on free TV. In response, President Ferdinand Marcos issued a warning to the station or else they will share the same fate of other networks, especially ABS-CBN.
Red: Home location of GMA 7 Manila Light red and red: Market audience of GMA 7 Manila Violet: Areas that may receive signals from GMA 7 Manila
When democracy in the Philippines was restored in the People Power Revolution in 1986, other television stations began to air, some with their original owners. The political instability of the country also added to the station's burden, when soldiers stormed into its studios for two days as part of a coup attempt to topple then PresidentCorazon Aquino.
In July 1987, GMA introduced its new dimension in television broadcasting as the network was transmitted in full stereo, dubbed as GMA StereoVision, and became the first Philippine TV station to broadcast programs in full stereo until 1998 when it switched to the current 120 kilowatt capacity.
On November 7, 1988, DZBB officially inaugurated a new 100,000 watt transmitter in Quezon City. Known as the "Tower of Power", which initially operated on a 50 kilowatt transmitting output from 1988 to 1998, the 777 ft (236.8 m) transmitter helped improve the channel's reception in Luzon, and was also the tallest man-made structure in the country at the time.[4]
By 1998, DZBB upgraded its transmission to 120,000 watt using its new solid state transmitter from Harris.[citation needed]
Digital television
Digital channels
DZBB-TV's digital signal operates on UHF channel 15 (479.143 MHz) and broadcasts on the following subchannels:
In February 2013, GMA Network conduct a digital test broadcast with the ISDB-Tb standard via its UHF channel 27 (551.143 MHz) frequency.
According to a December 2017 press release, the station's upgraded signal transmission covered the areas of Metro Manila, Rizal, Cavite, Laguna, Bulacan and parts of Pampanga, Bataan, Nueva Ecija and Batangas.
In 2018, National Telecommunications Commission released implementing rules and regulations on the re-allocation of the UHF Channels 14-20 (470–512 Megahertz (MHz) band) for digital terrestrial television broadcasting (DTTB) service. All operating and duly authorized Mega Manila VHF (very high frequency) television networks are entitled to a channel assignment from Channels 14 to 20.[5]
In 2019, the NTC, through a memorandum circular, authorized GMA to operate UHF channel 15 (479.143 MHz) as its secondary channel to expand the usage of channels 14-20 for digital TV broadcasts. Following ZOE Broadcasting Network's decision not to renew its joint venture (GMA News TV) with GMA after June 2019, and a subsequent planned reactivation of DWDB-TV's analog signal for the rest of the GNTV's analog broadcast run, third-party sources reported that the station's digital signal will move to the assigned channel 15 frequency after channel 11's blocktime deal with GMA expires.[6]
On May 15, 2019, GMA Network began to transmit its digital test broadcast on UHF Channel 15 (479.143 MHz) as its permanent frequency assigned by National Telecommunications Commission.[7]
Starting 27 February 2023, the video output of DZBB-TV, along with GMA Network's other digital stations, had been officially migrated to 16:9 widescreen format.
