Keysight Technologies X Series - Page 327

Keysight N9010A EXA Service Guide 327
L.O. Synthesizer/Reference Troubleshooting
A16 Reference Assembly Troubleshooting
Serial Prefix < MY/SG/US5648
The diagnostic LEDs are located near the oven oscillator near the right side of
the board. Refer to Figure 8-10. Table 8-5 lists the diagnostic LEDs and what
their status indicates.
Table 8-5 LED Activity
LED Number Description Status
DS1 When Program Code is Loading On=Loading code from EEPROM
Off=Ready
DS2 When 4.8 GHz Frequency is Low On=Fault (Output Frequency too low)
Off=Normal
DS3 When 4.8 GHz Frequency is High On=Fault (Output Frequency too high)
Off=Normal
DS4 Is the 4.8 GHz Reference PLL Locked? On=Normal
Off=Fault
DS5 Is the 4.8 GHz Vtune Optimized? On=Vtune centered in range
Off=Vtune off center. No real fault
DS6 Is the 100 MHz PLL Unlocked? On=Fault
Off=Normal
DS7 Is the 100 MHz PLL Locked? On=Normal
Off=Fault
DS8 Is the 100 MHz Out being properly
Detected?
On=Normal
Off=Fault
DS9 Opt. PFR Out Enabled On=Internal PFR enabled
Off= Internal PFR disabled (Ext. Ref. Mode)