Agilent Technologies 89410A Service Manual page 88

Troubleshooting the Analyzer
To troubleshoot source and calibrator out failures
8
Check DAC signals.
a
Press the following keys:
]
[Preset
[ ]
Source
[ source on]
b
Using a logic probe, check that the TTL signals listed in the
following table are toggling.
c
If any of the signals are incorrect, the A30 Digital Source assembly
is probably faulty.
d
If the signals are correct, the A35 Analog Source assembly is
probably faulty. Before replacing the A35 Analog Source
assembly, go to
and do Step 7 to check the -8 V power supply.
1-70
Test Location
A91 J6 pin 4A
A91 J6 pin 4C
A91 J6 pin 5B
A91 J6 pin 6A
A91 J6 pin 6C
A91 J6 pin 7B
A91 J6 pin 8A
A91 J6 pin 8C
A91 J6 pin 9B
A91 J6 pin 10A
A91 J6 pin 10C
A91 J6 pin 11B
page 1-15, ''To troubleshoot the power supply,''
Signal Name
DAC[0]
DAC[1]
DAC[2]
DAC[3]
DAC[4]
DAC[5]
DAC[6]
DAC[7]
DAC[8]
DAC[9]
DAC[10]
DAC[11]