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PerformanceCheckprocedure- 4g4Al4g4ApServiceVol. 1

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SPAN/DIVto 50 Hz and RESOLUTTONBANDWIDTHto 10 Hz .

h.Tunethe CENTERFREQUENCYcontrotto posi- tion the signalso its slope can be determined.Again, slope determinationrnay be made easier by switching VIEW B off, and usingSINGLESWEEPand SAVEA to treezethe displayat a convenientpositionon the grati- cule. The slope should calculate to approximately 2 Hzldivision.

i.DeactivateSAVE A and SINGLESWEEPand switch the TIME/DIVto 20 ms. ActivatezERo spAN and positionthe displaynear centerscreenso the verti- cal excursionsper horizontaldivision(20ms) can be measured.ResidualFM must not exc€ed12 Hz within anyonehorizontaldivision.

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Figure 4-5.Typical display for measuriag residual FM.

f.lf SAVEA was usedin part e, de-activateSAVEAand vtEW B. Activate zERo spAN, set TtME/Dlv to 20 ms, and set CENTERFREQUENCYcontrotto posi- tion the displaynear centerscreenas shown in Figure 4-58. Use SAVE A to freeze the display for easl in measuringFM. The peak-to-peakamplitude of the display (numberof verticaldivisions)within any given horizontaldivision, scaled to the vertical deflections accordingto the slope estimatedin part e, is the FM. ResidualFM mustnot exceed7 kHzover20 ms (1 divi_ sion).

S.Press <Blue-SHIFT>10 dB/DlV to re_enable the phasetock,then set the FREQUENCYto 100MHz and switchthe TIME/DIVto AUTO. Reducethe FREQ

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7.Check Frequency Span/Div Accuracy (Within5% of the selectedspan/div)

(Measuredoverthe centerI divisionsof a 10 divi- siondisplay)

Span accuracyis checked by noting the displace- ment of calibratedmarkersfrom their respectivegrati- cule lines over the centereight divisionsof the screen. The frequencyspan/div accuracy is checked,for all SPAN/DIVsettingson band 1, at 100kHz/Divon band

2, {2nd LO check)and at 500 MHz/Divon band4. The accuracyof the 1 GHz, 2 GHz. 5 GHz, and 10GHz spanldiv of the upper bands is directlyrelatedto the 100 MHz/Div and 200MHz/Div spans. Therefore,the 1 GHzlDiv, 2 GHz/Div, 5 GHz/Div, and 10GHz/Div spansare not includedin this procedure.

FREOUENCYSPAN/DIVrangeis 20 Hz to 100MHz for the 0 to 7.1 GHz bands,in a in a 1-2-5 s€quence when selected via the SPAN/DIV control, or up to

400MHzwhenselectedvia the DataEntrykeyboard. a. Setthe SpectrumAnalyzercontrolsas follows:

CENTERFREOUENCY 1 GHz

SPAN/DIV100MHz

RESOLUTIONBANDWIDTHAUTO

REFLEVEL-30dBm

TME/DVAUTO

VERTTCALDTSPLAY 10dB/DtV

b.Applythe CAL OUTsignalto the RF INPUTand set the CENTERFREQUENCYto align the 100MHz markersso the 100MHz/divaccuracycan be measured over the centereightdivisionsof the display.lt maybe necessaryto changethe REFLEVELto obtainadequate markeramplitude.Maximumdeviation(seeFigure4-6) mustnot exceed5 MHz/Div,

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