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PerlormanceCheck procedure_ 4g4A/494ApServiceVol. 1

8.Check Marker Accuracy

Accuracywith the 1st LO untockedis * {(20%of the Span/Div or Resolution Bandwidth,whichever is greater)+ (CF x ReferenceFrequencyEnor) * 15N kHzl.

Accuracy with 1st LO tocked is * ((20% of the Span/Divor ResolutionBandwidth,whicheveris greater).+(CF x gglsr.nce FrequencyError)+ (2N + 25)Hz).

(A markeraccuracyis 1% of the measuredspan)

The 1st LO is not phas€-lockedin Fre_ quency Span/Div settings >200 kHz. For Span/Divsettings (200kH2, the lst LO may be unlocked by first going to an unlockedSpan/Divsettinganddisablingfre_ quency corr€ctions (Btue_SHtFT1OdB),

then-spanningdown to a Span/Divsettint (200 kHz.

QuantityN is the lst LO harmonicnumber used for the first conversion.press HELp and <Blue-SHIFT>BANDV for the value of N.

a.Checkslngle markeraccuracy.

(1)Applythe CAL OUTsignattothe RF tNpUT.

(2)Set the SpectrumAnalyzercontrolsas follows:

CENTERFREOUENCY 600MHz

sPAN/DlV	500kHz
AUTORESOLN	On
REFLEVEL	-20 dBm
VERTICALDISPLAY	10dB/Dtv
TrME/DtV	AUTO
TRlGGERING	FREERUN

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(3)Disable frequency corrections by pressing <Blue-SHIFT>10dB/DlV.

(4)R_€setthe spAN/Dtv to 100 kHz white keeping the 600 MHz harmonicof the calibratorsignalneai center'screenwith the CENTER/MARKERFRE_ OUENCYcontrol. The 1st LO is now unlocked.

(5)Enablea single marker, and positionit on the signalbypressing<Green-SHIFT>PEAKFND.

(6)Checkthat the markerreadoutis within35 kHz of the centerfrequencyreadout.

(7') Press <Blue-SHtFT> 1OdB/DtV to enabte phaselock.

(8)Use the CENTER/MARKERFREQUENCYcon- trol to reposition the calibrator harmonic near center-screen.

(9)Press <Green-SHIFT>PEAK FNDto position the markeron the signal.

(10)Check that the marker frequencyreadout is within47 kHz of the centerfrequencyreadout. The factor(CF x ReferenceFrequencyError)is canceled whenihe CALOUTsignatis used.

b.CheckA markeraccuracy.

(1) Setthe SpectrumAnalyzercontrolsas follows:

CENTERFREQUENCY 0-60GHz

sPAN/DtV100MHz

AUTORESOLN On

REFLEVEL-20dBm

VERTICALDISPLAY 10dB/Drv

TtME/DtVAUTO

TRIGGERING FREERUN

(2)EnableA markersby pressing<Green-SHIFT>

A MKR, and tune one marker to a harmonicof the calibrator signal. Press <Green-SHIFT> MKR1*MKR 2, and tune the second marker to anotherharmonicof the catibratorsignal.

(3)Check that the A marker frequencyreadoutis within17oof the measuredspan.

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