Tektronix 494AP service manual Range, FREQSPAN/DIV MAX Autoresoln Reflevel, Minrf Atten, Timeidv

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Maintenance- 4g4Al4S4ApServtceVot. 1

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SWEEP OSCILLATOR		TO RF OT'TCOi.NECTOR			SP€CTRUT AIIALYZER U}IDER IEST	(
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Figurc 6-28. Baselinelevefingtert setup.

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(6)Adjust R1069for a triangular waveformacross the screen. SeeFigure6-g1b:

f/) ResetRl0tg throughRl061 to midrange.

(8) Sweep Band4 in 2 GHz increments. Set the Spectrum Analyzer as foltows for th€ first 2 GHz portionof Band4.

FREQUENCYRANGE 5.4-18.0 GHz

FREQUENCY6.4GHz

FREQSPANiDtv200MHz

RESOLUNONBANDWIDTH 1 MHz

REFLEVEL-20 dBm

VERTICALDISPLAY 10dBiDtv

TrME/DVAUTO

PEAK/AVERAGEFully Counter-

clockwise

MAXHOLDOn

(9)	Check that flatness is	within +g.S dB. tf
flatnessis out of limits,activateSAVEA and WIDE
MDEO FILTER,and deactivateMAX HOLD. Reset
REFLEVELso the baselineis on the screen.
(10)	potEntiometers
	.Adjust-leveling	to compensate
for abnormalities
	in tha SAVEA disptay.

(11)Recheck the 2eHz window for flatness. Proceed checking the Band5 flatness in 2 GHz increments.

l. Adjustthe slop€ of band5 as follows:

(1)-Resetthe Sweep Oscillatorso it sweepsfrom

15 GHz to 21 GHz (MarkerSweepland set the out_

Plt 9o the power meter reads approximately -10dBm.

(2)Set R1070(Band5 Stope)on the Mdeo proces- sor board,fullycounterclockwise.

(3)Setthe SpectrumAnalyzercontrolsas follows:

FREQUENCY	15-2i GHz
RANGE
FREQUENCY	15GHz
FREQSPAN/DIV	MAX
AUTORESOLN	On
REFLEVEL	-1OdBm
MINRF ATTEN	OdB
VERTICALDTSPLAY	10 dB/Dtv
TIMEIDV	50 ms

The UNCALindicatorwiil tight.

(4)Selecta 15 GHz markeron the SweepOscillator andsettheoutputfor --10 dBm.

(5)Activate2 dBiDlV and set the REFLEVELsuch that the signal amplitudeis approximatety6 divi- sions. Set MANUALPEAKfor maximumresponse or activateAUTOPEAK.

(6)Changethe SweepOscillatorto AutomaticInter- nal Sweepand set the SweepTimefor 100s or its slowestsweep.

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