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Troubleshooting
3 - 20
68P02963C70-O
Closed Loop Power Test
This test should be carried out only after the successful completion of the previous tests.
No
Yes
No
No
Yes
Yes
Tune the radio on PATS.
Is the
radio close loop
output power <28dBm
or >31 dBm?
OK
OK
Check the elements: coupler U806, R815, R818,
R825, R826, C817. Replace if faulty and repeat the
Close Loop test.
Does the
close loop power
problem still
exists?
Measure the LO power on pin 24 MVCO
of the LNODCT U803 (800-400 mVp-p
(single ended) swing into a 50Ohm load).
Is the LO power OK?
Replace LNODCT, perform
Open Loop Power test and
Close Loop Power test.
Check R838, C814 replace if faulty, repeat
Close Loop Power test. If the problem still
exists replace LNODCT U803 and repeat
Open Loop Power test and Close Loop
Power test.
Содержание MTH500
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Страница 14: ...Foreword xiv 68P02963C70 O THIS PAGE INTENTIONALLY LEFT BLANK ...
Страница 18: ...Overview 1 4 68P02963C70 O THIS PAGE INTENTIONALLY LEFT BLANK ...
Страница 50: ...Theory of Operation 2 32 68P02963C70 O THIS PAGE INTENTIONALLY LEFT BLANK ...
Страница 76: ...Troubleshooting 3 26 68P02963C70 O Offset VCO Test ...
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Страница 82: ...Programming the Radio 4 4 68P02963C70 O This page left blank intentionally ...
Страница 100: ...Maintenance 5 18 68P02963C70 O Figure 23 Exploded View 1 2 3 4 5 7 6 X6 8 ...
Страница 101: ...Maintenance 68P02963C70 O 5 19 Figure 24 Exploded View of Chassis Assembly 9 12 13 10 11 14 ...
Страница 102: ...Maintenance 5 20 68P02963C70 O ...
Страница 103: ...MTH500 Detailed Service Manual COMPONENT BOARD LAYOUTS 68P02963C70 O 6 1 Component Board Layouts ...
Страница 104: ...MTH500 Detailed Service Manual COMPONENT BOARD LAYOUTS 6 2 68P02963C70 O This page intentionally left blank ...
Страница 109: ...MTH500 Detailed Service Manual Schematic Diagrams and Parts Lists 68P02963C70 O 6 7 Schematic Diagrams and Parts Lists ...
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Страница 140: ...Replacement Parts and Kits 6 68P02963C70 O ...
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