Tektronix RSA3408B, Service Manual

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Troubleshooting
RSA3408B Analyzer Service Manual
5- 79
Table 5- 8: Symptoms and faulty modules
Symptom (other functions are assumed to be normal) Possible faulty module
No trigger signal is output from the TRIG OUT connector on
the rear panel.
A42 DIFP board
Cannot triggered with an external trigger signal. A42 DIFP board
No reference signal is output from the REF OUT connector on
the rear panel.
RF5 module
Displayed signal frequency shifts for an external reference
source.
RF5 module
An external IQ signal is not displayed, or the signal level is
incorrect.
A10 A/D board
Signal is not displayed or signal frequency shifts when you set
up a specific (or in a specific range of) center frequency.
RF3 module or
RF4 module
Noise floor excessively increases or spurious signal appears at
specific span setting.
A42 DIFP board
Noise floor intermittently jumps high regardless of span or
center frequency settings.
A10 AD or
A42 DIFP board
Correct signal frequency and/or level are not displayed when
span is set to a value greater than 20 MHz.
RF3 module or
RF4 module
Acquisition freezes when you set a specific span. A42 DIFP board
Error message is displayed when you execute self gain-calibra-
tion.
A100 Cal generator board or
RF4 module
GPIB does not work. A50 motherboard or
A70 DC power board
Cannot turn off power using the On/Standby switch. CPU board or
Windows hangs up.
Cannot turn off power using the On/Standby switch while the
power LED is not illuminated.
Power supply 3
Cannot turn off power using the On/Standby switch while the
power LED is illuminated.
CPU board
A front-panel key does not respond. A60 Front key board,
CPU board, or
Windows hangs up.
The frequency trigger does not work. A42 DIFP board
Baseband mode does not work. A10 A/D board
RF1 band does not work. RF2 or RF3 module
RF2 or 3 band does not work. RF3 module,
Bandpass filter, or
A100 Cal generator board