Tektronix 494AP service manual O o o o, Maintenance- 494l4g4Ap ServlceVot

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Maintenance- 494[l4g4Ap ServlceVot. I

Test Osciltoscope

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				J231
			829 MHz Converter	I
	Tracking Generator		lF Section	Y
I	lo	. O
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	IRF	Aur.
__a^	Out

Return Loss Bridge

(Device Under Test)

2 7 2 7 - 1 5 7

Flgure 6-14. 829 MH: filter test equlpment setup.

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g. .With the adjacent resonator (second) shorted to ground, adjust the series capacitance by benOing tne tab so the response on the_spectrumanalyzer display is

centered at 829 MHz (see Figure 6_16A).

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h.Now move the shorting strap (screwdriver)to the next resonator and adjust the tab of the second resona_ tor for a responseas indicatedin FigureOiOe.

i.Remove the short from the third resonator and short the fourth resonator. Adjust the third resonator for a response similar to that snown in Figure 6-17A.

j.Repeatthe procedurefor the final(fourth)resona- tor for a responsesimilarto that shownin Figure6-178.

k.Checkthat the return loss is equalto or greater than12 dB.

l.Disconnectthe return loss DeviceUnder Test leadto the pettotajackJ1029on the g29MHzAmptifier board, then unsolderand r€connectthe jumperto the amplifieroutput.

m.Replacethe 829 MHz Convertercoverand rein- stallthe assemblyin the SpectrumAnlyzer.

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