Keysight N5264A Service Manual page 44

Troubleshooting
Power Up Troubleshooting
1. Unplug the A19 test set motherboard ribbon cable from the A19 test set
motherboard (refer to
Motherboard" on page
2. Unplug the A19 test set motherboard to A20 IF multiplexer board ribbon
cable from the A20 IF multiplexer board (refer to
the A20 IF Multiplexer Board" on page
3. Unplug the front panel interface cable from the A1 front panel interface
board (refer to
Assembly" on page
4. Remove the A12 board (refer to
and A12 Boards (For analyzers with serial numbers prefixed
MY/SG/US5144 and below.)" on page
5. Remove the A11 13.5 GHz synthesizer board (refer to
Replacing the A10, A11, and A12 Boards (For analyzers with serial
numbers prefixed MY/SG/US5144 and below.)" on page
6. Remove the A10 frequency reference board (refer to
Replacing the A10, A11, and A12 Boards (For analyzers with serial
numbers prefixed MY/SG/US5144 and below.)" on page
7. Remove the A18 GPIB board (refer to
GPIB Board" on page
the A17 CPU board assembly.
8. Unplug the A51 hard disk drive from the A17 CPU board (refer to
"Removing and Replacing the A51 Solid State Drive (SSD)" on page
The minimum required assemblies to power up the analyzer are:
— A16 power supply
— A15 midplane board
— A14 system motherboard
— A17 CPU board
To further isolate the failure in the three remaining assemblies, measure the
resistance (with the power turned off) from the power supply test points to
either ACOM or DCOM.
Make sure that the only assemblies plugged in are the four minimum
required assemblies listed above.
Check for shorts (zero ) or very low resistance (approximately 1 ). If a short
or low resistance is measured, isolate each of the remaining four boards in the
following order, and recheck the shorted test point after each board is
removed. You should be able to determine if the shorted condition has
changed.
Isolate the remaining three assemblies:
4-12
"Removing and Replacing the A19 Test Set
7-28).
"Removing the A1 Front Panel Interface Board and Keypad
7-9).
"Removing and Replacing the A10, A11,
7-26). Reinstall the A16 power supply assembly and
"Removing and Replacing
7-30).
7-13).
"Removing and
7-13).
"Removing and
7-13).
"Removing and Replacing the A18
Keysight N5264A Service Guide
7-34).