2. Service
Assembly/Module Diagnostic Trees (Diagnostic Section 3)
119
3.8.4.0 A18J4 Signal Input Test
1
Disconnect cable from A18J4 and reconnect that cable to the input of a 2-
way 3-dB. power splitter.
2
Connect one of the power-splitter outputs to A18J4 and the other to a
spectrum analyzer.
3
Verify the frequency of the signal on the spectrum analyzer to an accuracy of
100 kHz.
QUESTION: Is
frequency
<
87.3 MHz?
Yes, Go to, 3.8.4.1.
Is
frequency
>
87.4 MHz?
Yes, Go to, 3.8.4.2.
Is frequency between 87.3 and 87.4 MHz? Yes, Go to, 3.8.4.3.
3.8.4.1 A18 Mon Voltage Test
1
Measure dc voltage on the A18 mon terminal with a scope.
2
Verify that the average voltage is less than +0.05 Vdc?
QUESTION:
Is the average voltage less than +0.05 Vdc?
If Yes:
Go to, A15 diagnostic tree.
If No:
Remove power, replace A18, and retest.
3.8.4.2 A18 Average Mon Voltage Test
1
Measure dc voltage on the A18 mon terminal with a scope.
2
Verify that the average voltage is more than +0.45 Vdc.
QUESTION:
Is the average voltage more than +0.45 Vdc?
If Yes:
Go to, 3.6.1.0 (A15 diagnostic tree).
If No:
Remove power, replace A18, and retest.
3.8.4.3 Mon Signal AC-Content Test
1
Examine voltage on the A18 mon terminal with a scope.
2
Observe the signal and measure its ac content.
QUESTION:
Is the ac content more than 10 mV?
If Yes:
A18 is probably at fault, (although A15 is suspect).
Remove power, replace A18, and retest.
If No:
A18 is nominally operational.
Содержание 5071A
Страница 2: ......
Страница 40: ...1 Performance Tests Verifying Specifications 5071A Complete Performance Tests 24 ...
Страница 48: ...2 Service Pre Troubleshooting Information 32 Figure 2 1 Instrument Top View ...
Страница 147: ...3 Theory of Operation Functional Block Descriptions 131 Figure 3 2 5071A Overall Block Diagram ...
Страница 148: ...3 Theory of Operation Functional Block Descriptions 132 Figure 3 2 5071A Overall Block Diagram Continued ...
Страница 164: ...3 Theory of Operation Functional Block Descriptions 148 Figure 3 3 A1 Power Supply Distribution Schematic Diagram ...
Страница 166: ...3 Theory of Operation Functional Block Descriptions 150 Figure 3 4 A1 Slot Module Interconnect Diagram ...
Страница 168: ...3 Theory of Operation Functional Block Descriptions 152 Figure 3 5 Power Supply Block Diagram ...
Страница 171: ...3 Theory of Operation Functional Block Descriptions 155 Figure 3 7 Opt 048 A1 Slot Module Interconnect Diagram ...
Страница 172: ...3 Theory of Operation Functional Block Descriptions 156 Figure 3 8 Opt 048 Power Supply Block Diagram ...
Страница 173: ......
Страница 175: ...3 Theory of Operation Functional Block Descriptions 159 Figure 3 9 A1 Component Locator Diagram ...
Страница 194: ...5 Replaceable Parts How To Order A Part 178 ...
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