External Test Failure Troubleshooting - Agilent Technologies E4991A Service Manual

External Test Failure Troubleshooting

When the external test fails, replace the faulty assembly as shown in Table 4-2.
Table 4-2 Troubleshooting Information for External Test Failure
Test First Failed Test
No.
1
*1
FRONT KEY & LCD
SOURCE
2
3 OUTPUT ATT
4 INPUT ATT
5 IF GAIN
6 FRONT ISOLATION
7 TEST HEAD
8 DC BIAS TEST
9 Z MEAS
*1.If "FRONT KEY &LCD" test fails, verify A22 Front Panel Keyboard, A51 LCD, A21
Analog Interface Board and A26 Display Board.
: Most suspicious assembly
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: Suspicious assembly
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: There is some possibility of a fault
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Chapter 4
External Tests Failure Troubleshooting
Probable Faulty Assembly
A1 Ref A3 A4 A2 DC
OSC Source Reciever Bias(001)
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Troubleshooting
A5 Freq A6 Test
Ref(1D5) Head
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