Keysight Technologies N5290/1A PNA Series Service Manual page 93

N5290/91A Troubleshooting
N5292A Test Controller Troubleshooting
d. Ensure the TSMB DC Supply indicator LEDs are on. If not, suspect
e. If the voltages on the power supply voltages are not correct:
f. If the fan is not working and all +3.3V are OK and the DC Supply
Keysight N5290/1A Service Guide
power supply (0950-0516) or front panel Standby switch. Using a
DVM measure the power supply terminal connections. Refer to the
label on the power supply for voltages on the terminals screws.
Refer to "Verifying the A1 power supply" on page
i. Turn off the power switch.
ii. Then lift the TSMB.
iii. If the DC Supply LEDs were on, disconnect bias cables (J60 &
J61) and amp cables (J10, 11, 12 and 14) to the TSMB and
re-install the board.
iv. If the indicator LEDs are on, suspect the A3 LODA.
the A2 LOPA, A3 LODA, and A4 Phase Compensation Boards"
on page 4-22 .
LEDs are on, replace fan. Refer to TP20, F6, and
page 4-11, Figure 4-3 on page
4-17.
Table 4-1 on
4-12, and Figure 4-4 on page
"Verifying
4-13.
4-7