Tektronix RSA3408B, Service Manual

Page: 196 / 250

Troubleshooting
5- 68
RSA3408B Analyzer Service Manual
Use this procedure to determine
if an analyzer problem is caused
by the low voltage power supply.
Connect the analyzer to the correct
power source. Turn on the Principal
Power Switch on the rear panel, and then
the On/Standby Switch on the front panel.
Yes
NOTE. Turn off the analyzer using the:
H
On/Standby Switch when Windows XP is running.
H
Principal Power Switch when Windows XP is not booted.
Are
the two fans
on the left side
working?
Is
the fan on
the CPU board
working?
Do
the twelve
power indicators (LED) on
the A70 DC power board
light? (See Figure
5--39.)
Yes
Yes
The power supply is OK.
Yes
Check the power supply voltages on
the power supply 1 , 2, and 3 modules
(See Table 5--6 and Figure 5--38).
Yes
Replace the A70 DC power board.
Check the test point voltages on A70
(see Table 5--7 and Figure 5--39).
Are
the voltages
OK?
Yes
Check the test point voltages on A70
(see Table 5--7 and Figure 5--39).
Yes
Are
the two fans
on the left side
working?
Is
the fan on
the CPU board
working?
Yes
Replace the fan.
No
Replace the fan.
No
No
Are
the voltages
OK?
Are
the voltages
OK?
Replace the failed power supply module.
Check the power supply voltages on
the power supply module
(See Table 5--6 and Figure 5--38).
Yes
Are
the voltages
OK?
No
Remove short circuit on the loading side.
No
No
No
No
No
Figure 5- 34: Troubleshooting procedure 1 — Power supply system