ClassA - tridimas electronics

AMAvailable for:ClassATRF HEADEND• Terrestrial TV reception, standard DVB-T /MPEG-2 (EN 300 744).• Digital to analogue transmodulationprocess (COFDM - AM) that presents theclear TV programmes transmitted in CO-FDM terrestrial TV channels on conventionalVHF/UHF channels (VBS vestigial sideband; any TV system and colour system).• A TRF headend includes:- As many TRF receiving modules as freeto-airTV programmes to be distributed.- One HPA amplifier that amplifies the sumof the combined output TV channelsfrom the receivers.- One or more CFP power supply.- One or more rack-frames or wall fixingbase plates. The base plates can bejoined horizontally.- Usually, one housing unit- If the headend is voluminous, one ormore AMX-400 combiners.The TRF headends provide a TV multichannelsignal whose level is appropriate tofeed the distribution network. With a TRFinstalled in the headend, the end user doesnot require a Set Top Box or any additionaldevices to view the clear digital TV programsbeing distributed. An extension inputat the HPA amplifier allows easy coupling ofthe wideband 47-862 MHz signal providedby another existing headend.FUNCTIONAL DESCRIPTION OF THETRF RECEIVERSA TRF receiving module carries out thecomplete channel processing from the inputto the output:- tunes a COFDM digital channel within theBIII or UHF bands,- selects a TV programme from the multiplexbeing received, and- directs it to a conventional TV channelwhich is selectable throughout the 45-862MHz band..Range includes different models for VSBoutput channel spectrums; for B/G, D/K, I,or L TV systems; and for mono sound, or A2or Nicam stereo/dual sounds.Mains features:- Central Input Frequency (125 kHz increments).- Bandwidth (7 or 8 MHz).- Hierarchy Level (high or low priority).- TV Programme and Audio Service.- Parameters of the output TV channel(video carrier frequency, TV system, coloursystem, video modulation depth, audiomodulation index, carrier level ratio, outputlevel).- Image Format. Possible conversions are16:9 to 4:3 Pan&Scan and 16:9 to 4:3Letter-Box.Simple cabling of TRF headendsThe TRF receiving modules features twodirectionally coupled input and output ports.Antenna signal can therefore be directlyfed into the input port of the first module,which in turn passes in through the couplerto the next and so forth. On the output side,the same procedure is repeated whichforms the channel couplign. The sum of thecombined channels is turn connected in thesame way to the drive amplifier _the HPAmodule or an external wideband amplifier_which then feeds the distribution network.For power connection, each module has twoDC banana sockets that allow to build a +12VDC cascade. A third banana socket is availableto connect the power for an optionalmast-head pramplifier.An external video/audio loop, which is switchedunder control software, is available onmodel TRF-112.Local programming is carried out eitherwith the SPI-300 unit, which is connected toeach module individually. Remote programmingmay by carried out only if the HMScontrol unit is installed in the headend.2HeadendsIKUSI · CATALOGUE 201361