Specifications

Maxiva UAX
October 17, 2013
4‐7
888‐2693‐004 WARNING:Disconnectprimarypower priortoservicing.
Copyright©2013,HarrisBroadcast
Note
The table above provides only a rough estimate of the resulting power level. It does not take into account
any minor shifts in DRIVE due to compensating action in the LPU RF power control circuit.
4.3 LowPowerUnit(LPU)
Inadditiontothecontrolfunctionsdiscussedpreviously,theLPUalsoprovidesthemainexciterfunctionsforthe
UAXfamilyoftransmitters.Itconsistsofamodulatorsection(top2RUofLPU)andanamplifiersection(lower2RUof
LPU).TheLPUcanproduceupto100W(average)COFDMTVorATSCTVpower
,and150W(peakvisualwith10%
aural)analogTVpower.
TheLPUperf
ormsthefollowinggeneralfunctions:
• Inputsignalconditioningandswitching(inthecaseofredundantinputsignals)
• Channelencoding/modulation
• Linearandnonlinearpre‐correction
• UpconversiontothefinalRFchannel
• AmplificationtothefinalRFpowerlevel
TheLPUmodul
atorsectioncontainsuptosevencircuitboardsincluding:
• Signalproces sorboard.
• Precisefrequencyreferenceunitboard(PFRU).
• Up‐downconverterboard(UDC).
• Lowvoltagepowersupply(LVPS)board.
• Batterybackupboard.(option)
• TransmitterI/Ointerfaceboard.
• Analog,satellitereceiver,orASIoverIPinputboard(options)
4.3.1 LPUModulationOverview
Figure4‐5isanoverallblockdiagramoftheLPUmodulatorsection.Notethatthepowersupplyandbatterybackup
boardsha
venotbeenshownforthesakeofclarity.Thesewillbediscussedinasubsequentsection.
UAX16PA ‐0.6dB ‐0.6dB
UAX24PA ‐0.4dB‐0.4dB
UAX32PA ‐0.3dB‐0.3dB
Table4‐1PowerOutputwithSingleModuleRemoved
FailedModule