Address:18 Jiuxianqiaozhonglu, Chaoyang District, Beijing, China Zip:100016
BBEF’S DIGITAL TV TRANSMITTER
Under the organization of The State Coordination Group on HDTV Development, The State Science and Technology Committee invited tenders for the project of HDTV prototype system in 1996. BBEF got the tender of transmitter sub-project and developed the China’s first HDTV transmitter which support 8VSB and COFDM standards. It passed the appraisal organized by Beijing Science and Technology Committee in February 1999 and won the Science and Technology Advance Award.
On this basis, BBEF developed 3 models of DTV transmitters for the second stage of the State HDTV Program in 1999:
- 1kW(rms) solid state DTV transmitter TVU-D312,
- 1kW(rms) single tube (tetrode) DTV transmitter TVU-D311,
- 2kW(rms) single tube (diacrode) DTV transmitter TVU-D321.
In 2001, BBEF developed 2kW(rms) solid state digital TV transmitter TVU-D322 for Beijing Digital TV Testing Station.
FEATURES OF TVU-D322
TVU-D322 digital TV transmitter is composed of two1kW amplifier cabinets . The final stage of each cabinet consists of 8 PA modules. Their outputs are composed in a composition unit. Total output is 2kW(rms). The PA modules are centralized air-cooled. Connection between PA and its PS is direct. Every PA has its own on-board protection circuit for over-current, over-heat, over-driving, over-VSWR as well as soft starting circuit of RF output. Transmitter itself is also equipped with protection circuits for over-VSWR and phase lacking.
The transmitter support 8VSB and COFDM standards.
SPECIFICATIONS:
DTV standards 8VSB/COFDM Bandwidth 6MHz or 8MH Operating frequency 470~800MHz Frequency stability ±300Hz/3 months IF 8VSB：44MHz COFDM:36.15MHz (Other IF is permitted) IF input level 0dBm ± 3dB IF input impedance 50Ω IF input connector BNC IF input reflecting loss Better than 30dB Output power 2kW (rms) RF output impedance 50Ω RF output connector 339 IEC-50-80-1 3 1/8 " (flange) RF output spectral mask: Inband smoothness: ±0.5dB ±4.3MHz（COFDM）:Better than -35dB ±3.125MHz(8VSB):Better than -35dB Rejection of adjacent channel:Better than -42dB Quadric harmonics:Better than -60dB Phase noise Better than -100dBc/Hz @10kHz Ambient temperature 5 ∽ 40℃ Relative humidity 95% Air pressure 86 ∽ 106kPa Cooling Forced air Mains power 3 phases 4 wire, 380 +19/-38 V, 50±1Hz Size（W×H×D?/sup> 2200×1900×1500mm (combiner and bandpass filter is not included)
