Keysight Technologies X Series Service Manual page 243

Front End Control Troubleshooting
A15 Front End Control Assembly Troubleshooting
Power Supply Verification
Looking at the test board, verify power supply green LED's DS5, DS6, DS7 and
DS8 located under the J2 connector are turned on. Additionally red LED's DS9
and DS10 should also be on. The power supply voltages are listed in the table
below.
If any of the power supply LED's are not turned on, see
and Initialization
Input Attenuator A Control Logic Verification (Option 503, 507, 513,
526)
Press AMPTD, Attenuation 0 dB on the analyzer.
Attenuation LED's DS15-20 on the test board should be off.
When the input attenuation is changed from 0 dB to 2 dB, the 2 dB Step LED
DS15 should illuminate. When the input attenuation is changed from 2 dB to
4 dB, DS15 and DS16 should be illuminated as per
2 dB and 4 dB settings are only available on analyzers with Option FSA, Fine
Step Attenuator.
If this is incorrect, the most probable cause is the A15, Front End Control
assembly.
Keysight N9010A EXA Service Guide
Table 6-4
LED
DS5
DS6
DS7
DS8
DS9
DS10
Troubleshooting".
Table 6-5 Input Attenuator A LED's
Attenuator Setting (dB)
0
a
2
a
4
a. These settings available only if analyzer has Option
FSA, Fine Step Attenuator.
Power Supply Voltages
Power Supply
+15 VDC
+9.0 VDC
+5.2 VDC
-15 VDC
+25 VDC
+25 VDC
Chapter 2, "Boot Up
Table 6-5. Note that the
DS15 DS16
OFF OFF
ON OFF
ON ON
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