Tektronix service manual A o O o, O o o, 494A/494APServtceVot.1

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494A/494APServtceVot.1

LISTOF ILLUSTRATIONS(Conr.)

Figure					Page	Flgure				Page
5-21	PreseleetorDriver						constructiondetails.	..................		6-gg
	adjustment
	setup			............	5_22	6-23	2182MHz2nd LO PhaseLock
5-22	Preselector
	Drivertest point						adjustmentsetup	..............		6_39
	and adjustmentlocations			...........		6-24	Tuneand SweepRange
5-23	Test equipment				S_Zg
	setupfor band						adjustments	............		641
	levelingadjustment.		,			6-25
							3rd Convertertest points
5-24	Bandlevelingadjustment				S-24
	gaindiodelocations.		and				andadjustments	............		6_43
				...-	.....,,,....5-24	6-26	FirstConvertersetupfor adjustment			6-45
5-25 Test equipment
	s€tupfor adjusting					6-27 1st LO Driverboardadjustment
	the phaseLockassembly
							andtestpointlocations
5-26	PhaseLockassemblyadjustment				5 26	6-28				646
							Baselinelevelingtest setup,
	andtestpointlocations			,						.....647
						6-29	Typicalbaselinelevelingresponse			,
5-27	Option42 adjustment				S_27
										649
	equipment	test				6-30	Baselinelevelingadjument
	setup			.............			andtestpointlocations
					S_g0	6-31				649
							Typicalbaseline
6-1 Surface-mountedcomponents							compensationresponse.	...........		6_49
						6€2 A15throughA12in
	leadconfiguration.		....................
6--?							microcomputertest mode.		.......	6-52
	Diodepotarity				6 16
	markings.				..........	6-33	Fourmainbloackselectoutputs
	Multipin(harmonica)				6-18
9-9	Servicing	connectors					of addressdecoderU2045.		......	6_59
					6_1g
9-1	thevR assembty.				......6_19	6-34	RAMselectoutput
	Topdeckassembties
9-9	RFdeckassemblies				,-...6-20		in relationto O'XXX.	...................		6-53
6-6				................		6-35	RAMsetectoutput
6-7	Removing				6_2.1
	the 1st LO						in relationtoTffi.	...................6-5g
	Interfaceboard.
					.....6-25	6-36	-UOand
	Fanassembtymounting.						S1050setecttines
9-9				..........	6-26		in relationto oxxx			6-53
	110MHzlF returnloss
6-9						6-37	ChipselectsY0,Y1,yS,
	adiustment			............	6-2T			...........		6-54
	setup						andY7 in retationtoT/O-.
6-10 110MHztFtestpoints						6-38	ChipselectsY2,Y4,andy6
	andadjustments			............
						in retationtd:IIO.			.. 6-54
6-11	2072MHzConverterbias				6-2g		6-39
						Instrumentbuscheck.		..............		6-55
_	adjustments.			..........	6_2g
6-12 829MHzLO test points
	andconnectors			............		7-1	Crosssectionof
6-13	829MHzamptifiertest				6-29
							a four-cavityfilter		..........7-g
	iackandjumper.				....6_30	7-2
6-14							Equivalentcircuitof
	829MHzfiltertest
							thefour-cavityfilter.	..................		7-g
	equipment
	setup			.............		7-3	Simplifieddiplexerdiagram.			.....7-19
6-15	829MHz Converterfilter				6-gi
						7-4	Equivalentac circuitof
	tunetabs.			.............
6-16	Correctresponsefor 929 MHz				6-32	7-S	an 829MHzamplifier			7-14
							Equivalentdc circuitof
					.... 6-92
	first and secondresonators.						an 829MHzamplifier			7,.......-'t4
6-17	Correctresponsefor 829 MHz					7-6
							Blockdiagrarnof the phaselock loop
	thirdandfourthresonators						in the829MHz2ndConverter			7-16
6-18	2182MHz2ndLO frequency				6 9g	7-7
							Bridged'T"attenuator
	accuracy
-	testsetup				.........		equivalentcircuit			7-lg
6-19	2182MHzphase	Locked2nd LO				7-8	Blockdiagramof a three
	adjustment			............	6_96
6-20	setup						stagelog amplifier			7-29
	16-20 MHzphaseLock		circuittest			7-g	Logamplifiergaincurve
	pointandcomponent
		locations				showingbreakpoints	.................		7-90
6-21	2182MHz2ndLO adjustment				6_32
						7-14 Curveshowingend-of-range
6-22	Coaxialtest probe					7-11	for a log amplifier			7-gO
							Simplifieddetectorcircuit.		........,2-gz

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