Agilent Technologies 89410A Service Manual page 95

operating correctly. This is caused by the ADC dither function.
The noise floor should settle after about 3 minutes and should
not affect the self-test results.
3 Step 3. Exchange channel 1 and channel 2 A/D Converter assemblies,
then check for failing tests.
a
Set the power switch to off ( O ).
b Exchange the channel 1 A21 A/D Converter assembly with the
channel 2 A/D Converter assembly.
c
Reconnect the cables as follows:
Channel 1:
Channel 2:
d
Set the power switch to on ( l ).
e Press the following keys:
]
[
System Utility
[ ]
auto cal off
]
[ more cal setup
[ off]
auto zero cal
]
[
Return
]
[
more
[ ]
diagnostics
[
service functions
1125
[ ]
enter
[ ]
test log
]
[
Return
[ ]
functional tests
[ ]
ADC
(wait for test to finish)
[ ]
more
[ ]
input
(wait for test to finish)
[ ]
calibration
f If the channel that failed before the exchange still fails, the A10
Analog Input assembly in the failing channel is probably faulty.
g
If the other channel now fails, the A21 A/D Converter assembly in
the failing channel is probably faulty.
To troubleshoot two channel analyzer failures
A10 J2 to A21 J4
A10 J3 to A36 J2
A21 J1 to A60 J3
A10 J2 to A21 J4
A10 J3 to A36 J5
A21 J1 to A60 J2
]
Troubleshooting the Analyzer
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