Tektronix RSA3408B, Service Manual

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Troubleshooting
RSA3408B Analyzer Service Manual
5- 69
This procedure helps you
determine whether the LCD display
or the CPU module is bad.
Turn on the analyzer.
Does
the initial screen
appear correctly?
Does
the analyzer
respond correctly when
the front-panel keys
are pressed?
Yes
Yes
Change the reference level (AMPLITUDE
→
Ref Level) in one dB step by rotating
the general purpose knob.
No
Can you
hear the relays
working?
Is
the analyzer
shut down correctly when
the On/Standby switch
is pressed?
Yes
Yes
Display and CPU system is OK.
No
No
Unplug the coaxial cable W611 on
the RF6 module (See Figure 5--37).
Using another spectrum analyzer,
measure the output at the connector.
Is
the spectrum
measured as follows?
Frequency: 102.4 MHz
Amplitude: +6.5 dBm
±
3 dB
Connect an external display to the VGA
output connector on the side panel.
Then reboot the analyzer.
Is
the screen
shown normally on
the external
display?
Replace
LCD display,
LCD inverter, or
A62 Front connection board
Replace
A42 DIFP board or
A50 motherboard
No
Yes
Yes
Did
the BIOS setup
screen appear when
starting up the
analyzer?
No
No
Unplug the coaxial cable W611 on
the RF6 module (See Figure 5--37).
Using another spectrum analyzer,
measure the output at the connector.
Is
the spectrum
measured as follows?
Frequency: 102.4 MHz
Amplitude: +6.5 dBm
±
3 dB
Replace
Hard disk drive or
A62 Front connection board
No
Yes
Replace the CPU board.
Yes
Replace RF6 module.
Replace RF6 module.
Figure 5- 35: Troubleshooting procedure 2 — Display and CPU system