Tektronix 494AP Rhi, LO0, Vehticaldisplay, Peaiaverage, TIME/DIV Auto Triggering Freerun

Changestepll as follows:

6. CheckReslduatFM

[Within7 kHz over20 ms withthe 1st LO unlocked (SPAN/DIV>200kHzfor band1 andbands5 rhrough

12andSPAN/DIV>100kHzforbands2 rhrough4)1.

[Within(5 + N)Hzover20 ms withrhe 1stLO locked (SPAN/DIVs200kHzforband1 andbands5lhrough 12andSPANiDIV<100kHztorbands2 rhrough4)1.

Change'f-"

to readas follows:

f, ll SAVEA wasusedinparte,de-activateSAVEA and VIEWB.ActivateZEROSPAN,setTIME/DIVro20ms,and set CENTERFREQUENCYcontrolto posirionthedisplay nearcenterscreenasshowninFigure4-5BUse.SAVEAto freezethedisplayforeaseinmeasuringFM.Fortheexample in Figure4-5,theverticalamplitude(gp) overeach20 ms sweepinleryal(1div.)canvarybynomorethan7 kHz(O-7 div)

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Flgure 4-5. Typlcal dlsptay for measurlng resldual FM

Replaeestepl7 wtth the tollowlng:

11.CheckResolutlonBandwldlhand ShapeFactor (bandwidlhis within2O%ot lhe selectedbandwidth exceptfor10Hz.Shapefactoris7.5:1or lessexceptlor 10 Hz. 10 Hz bandwidth<150Hz@ -60dBc.

a.ApplytheCALOUTsignaltotheRFINPUTSet.the Spec{rumAnalyzercontrolsasfollows:

CENTERFREOUENCY	'lO0
	MHz
SPAN/DIV	l MHz
RESOLUTIONBANDWIDTH 3 MHz
REFLEVEL	-20 dBm
VEHTICALDISPLAY	2 dB/DIV
MINNOISE	Activated
PEAI(AVERAGE	FullyClockwise
TIME/DIV	AUTO
TRIGGERING	FREERUN

b. Measure6 dB bandwidthfor each ResolulionBand- widthas follows:

(1)ActivateMARKER MENUpushbutton.

(2)Select'7- ENTER BANDWIDTHNUMBER"

(3)Enter "6" with the keypadand terminatewith "dB'.

(4)ActivateBAND WIDTHmode pushbutton(<green- sHtFT>BANDWTDTH).

(5)Fromthe inlormationdisplayedon lhe CRT, record the 6 dB bandwidthin Table44.

NOTE

Span Arcurary is not a lactor when usingthe bandwidthmode.

(6)Check that the recordedvaluefor the 6 dB bandwidthis within the limitsas specifiedin Table 44.

(7)Using the values in Table 4A, measurethe 6 dB bandwidlhlor all remainingRESOLUTIONBAND- WIDTHsettings(except10 Hz).

c.Measurethe 60 dB bandwidthfor each Resolution Bandwidthas follows:

(1) Set the Spectrum Analyzercontrolsas follows:

SPAN/DIV	l MHz
RESOLUTIONBANDWIDTH 3 MHz
VERTICALDISPLAY	1OdBIDIV
WIDE VIDEO FILTER	Activated

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