Specifications

Section-3 Operation
October 17, 2013
3‐76
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3.8.2 RTACStatusScreens1&2
Figure 3-70 LPU RTAC Status Screens 1 & 2
Note
(RTAC Levels pre and post-filter bargraphs) The signal level range is -20dBm to +5dBm, but, if possible,
it is better to keep the RF sample levels at -5 dBm. Since the RTAC sample levels at are usually too high,
the RTAC sample level is adjusted by adding appropriate attenuation at the exciter sample input connec
-
tors.
Table3‐68XmtrHome>ExciterHome>Status>RTACStatus
Field Explanation
Levels SeeNote
sonLevelsfollowingthisTable
Pre‐Fil
ter Thisisabargraphindicationwhichgivestherelativepre‐filterRTACRFsamplelevel.
Post‐Fil
ter Thisisabargraphindicationwhichgivestherelativepost‐filterRTACRFsamplelevel.
SummaryEr
ror
LinearFa
ult Green=OK,Red=HPFfeedbackinvalid
LinearRFLev
el Green=OK,Yellow=levellow,Red=levelhigh
Non‐Linea
rFault Green=OK,Red=HPAfeedbackinvalid
Non‐Linea
rRFLevel Green=OK,Yellow=levellow,Red=levelhigh
DownconverterA
ttenuation
IF
Theam
ountofIFattenuationisgivenindB,whichshouldbegreaterthan6.5dB.Theattenuation
valuedisplayedhasaYellowbackgroundifthevalueis<6.5dBasawarningindication.
RF
TheamountofRFattenuationisgivenindB,whichshouldbegreaterthan6.5dB.Theattenuation
valuedisplayedhasaYellowbackgroundifthevalueis<6.5dBasawarningindication.
Mode(R
TACscreen2)
Switch
Thedo
wnconvertermustSwitchbetweenthevariousRFsampleinputssothattheRTACcircuits
canproperlycorr ectforlinearandnonlineartransmitterdistortions,thechoices:
>>Automatic(Aut
o):Thisisthenormalmode.Inthismode,thedownconverterinputsampleis
automaticallyswitche d betweenPostHighPowerFilterorPreHighPowerFiltertoaccommodate
theneedsoftheRTAC(RealTimeAdaptiveCorrector)circuit.
>>Manual:Thisisatestmodeinwhichthedownconverterinputislockedtothepresentinput.
ManualSe
lect SelectionsarePost‐FilterorPre‐Filter.
DownConverter
ASta
tusreadoutofwhichinputispresentlyselectedbythedownconverter:
Post‐Fil
terorPre‐Filter.