Keysight Technologies N5221A, Руководство по обслуживанию

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4-42 Keysight N5221A/22A Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
4. If the 800 MHz signal is not present and the analyzer does not have
mechanical switches, replace the receiver coupler. Refer to “Removing
and Replacing the A25–A28 Receiver Couplers and Mounting Brackets” on
page 7-39 .
5. If the 800 MHz signal is present and the analyzer has source attenuators
and bias tees, reconnect the cable to the receiver coupler and continue
testing at “Checking the A34, A35, A36, and A37 60-dB Source Step
Attenuators” on page 4-42
6. If the 800 MHz signal is present and the analyzer does not have source
attenuators and bias tees, replace the test port coupler. Refer to
“Removing and Replacing the A29–A32 Test Port Couplers” on page 7-41 .
Checking the A34, A35, A36, and A37 60-dB Source Step Attenuators
1. Locate the appropriate semirigid cable at the output of the source step
attenuator to be checked:
— Options 219 and 419
— Port 1; W72 of A34
— Port 2; W84 of A37
— Port 3; W76 of A35
— Port 4; W80 of A36
2. Using a 5/16-inch torque wrench, disconnect the semirigid cable at the
step attenuator.
3. Connect the spectrum analyzer to the open step attenuator connector. Set
the spectrum analyzer to measure a signal at 800 MHz.
4. If the 800 MHz signal is not present, replace the source step attenuator.
Refer to “Removing and Replacing the A34–A37 Source Attenuators, the
A38–A41 Bias Tees, and the A42–A45 Receiver Attenuators” on page 7-45 .
5. If the 800 MHz signal is present, replace the associated bias tee. Refer to
“Removing and Replacing the A34–A37 Source Attenuators, the A38–A41
Bias Tees, and the A42–A45 Receiver Attenuators” on page 7-45 .