Specifications

Maxiva UAX
October 17, 2013
5‐7
888‐2693‐004 WARNING:Disconnectprimarypower priortoservicing.
Copyright©2013,HarrisBroadcast
Figure 5-4 Cabinet Pre-Filter Directional Coupler
Note
Refer to Figure 5-4. Coupler and sample configurations will vary with transmitter size and configuration.
5.4.1 ForwardCalibrationOverview
Factoryforwardpoweriscalibratedat10dBbelowmodelpowerandat1dBabovemodelpower(e.g.,100Wand
1.25kWfora1.0kWdigitalsystem)toensuregoodmeteringlinearityoverthe fulloutputpowerrange.
Th
eforwardpowerreferencesampleistypicallytakenfromadirectionalcouplerbeforethemaskfilterinthe
systemandregulatesthepowerofthetransmitteroutputbeforeanyfilterlosses.
Thesy
stemforwardpowersampleistakenfromaforwardportonthepre‐filterdirectionalcoupler(showninFigure
5‐4).Theco
upledportwillhaveanattenuatorpadandassociatedcabling(andalsoatwo‐waysplitterifusedina
dualLP
Uconfiguration).TheintendedoperatingconfigurationhastheFWDsamplepadselectedsothatatfull
systemoutput(e.g.1.0kWforaUAX‐1000ATsystem,)thesample(s)attheLPUFWDinput(seeFigure5‐5)wi
llbe
approximately0dB
mafterfactoringincouplervalue,cablingloss,splitterloss(ifinstalled),andpadvalue.
Figure 5-5 LPU SYS FWD & REF Sample Inputs