Specifications

Maxiva UAX
October 17, 2013
5‐9
888‐2693‐004 WARNING:Disconnectprimarypower priortoservicing.
Copyright©2013,HarrisBroadcast
Caution
DO NOT DEPRESS THE POWER RAISE BUTTON FOR EXTENDED PERIODS
OF TIME WHILE RAISING POWER TO THE SPECIFIED CALIBRATION LEVEL.
HOLDING THE RAISE BUTTON IN CAN RESULT IN LARGE POWER
OVERSHOOTS THAT COULD DAMAGE THE PA MODULES. ADJUST POWER
SLOWLY BY MAKING DISCRETE BUTTON PRESSES WHILE CLOSELY
MONITORING THE EXTERNAL POWER METER FOR CHANGE. USE THE
DOUBLE UP ARROW GUI ICON TO RAISE POWER IN LARGER STEPS. USE
THE SINGLE ARROW ICON FOR SMALLER STEPS.
STEP 8 Lowpointcalibration:UsetheapplicableRaise/Lowerbutto ns(depending
onwhetheryouarecalibratingfromthefrontpanelorWebGUI)toadjust
thetransmitter’soutputuntilthepowermeterindicatesthevaluerequested
onthecalibrationscreen.Thisvaluewillbe10dBbelowthespecificmodel
power(e.g.50dBm[100W]ina1.0kWdi
gitalsystem).Onceastablereading
hasbeenobtainedonthepowermeter,pressSa vetoproceedtohighpoint
calibration.
Note
It is helpful to check the RF DAC value displayed (in Hex) on the calibration screen. In a system which is
properly configured and operating correctly, the low point power level should be obtained at a DAC value
of < 0x300. If you reach a DAC value 0x300 but are not close to the desired target for this step, please ver
-
ify the system is configured correctly, especially if this is a first time turn-on or other service work has
been perfo
rmed.
STEP 9
Highpointcalibration:AgainusetheappropriateRaise/Lowercontrolsto
adjustthetransmitteroutputuntilthepowermeterindicatesthevalue
specifiedonthecalibrationpage,whichwillbeatmodelnameplatepower
(e.g.61dBmina1.0kWdigitalsystem).Onceastablereadingis obtainedon
themeter,presstheSa
vebutton.
STEP 10 Youwillbepromptedtorestorethesystemtonormalconfiguration(thisis
mostlyapplicabletocalibrationswheresamplesar eswappedasapartof
theprocedure)beforeproceeding.
STEP 11 Proce dur ecomplete.
5.4.2.1 CalibrationErrors
If,uponcompletionofthecalibrationsequence,them essage’CalibrationError’isdisplayed,repeatthe procedure
andnotethedisplayeddetectorADCvalue.Ifyouareabletoobtainthespecifiedpowerlevelsasindicatedonyour
meter,buttheADCisindicatingnear‐zerovalues,oriftheADCvalueatthehi
ghpointequals(orislessthan)the
valueatthelowpoint,thesystemwilldiscardthecalibration.Themostlikelycauseofthisisamissingorincorrectly
connectedforwardsampletotheLPU.Pleaseensurethesampleisproperlyconnected:thetwosamplecablesare
labeledFWDandRFLDonthehe
atshrink.
Ifan
yPAsarefaultedduringthecalibration,thesystemwillconsideritinvalidanddiscardit.ReplaceanyfaultyPAs
andrepeatthecalibration.
5.4.3 SystemReflectedCalibrationOverview
Systemreflectedpoweriscalibratedoverarangecorrespondingto30dBto10dBreturnloss(1.05:1to2:1VSWR)
relativetofullsystemforwardoutput.Thesystempre‐filterdirectionalcouplerreflectedportsampleroutesthrough
apad,cables,andasplitter(inthecaseofadualLPUsystem)totheref
lectedinput(s)oftheLPU(s).Thepadvalueis
selectedpersystemsuchthatafterfactoringincouplingvalue,pad,cableandsplitterlosses,thesampleintothe
LPU(s)willbeapproximately0dBmwitha10dBreturnloss,and‐20dBmwitha30dBreturnloss,relativetofull
systemoutputpo
wer.