Keysight N5227B, Service Manual

Page: 122 / 415

4-44 Keysight N5227B Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
Perform the following checks in the order presented.
Checking the A29, A30, A31, and A32 Receiver Couplers
1. Locate the appropriate semirigid cable at the output of the receiver
coupler to be checked:
— Options 200 and 400
— Port 1; W19 of A29
— Port 2; W31 of A32
— Port 3; W23 of A30
— Port 4; W27 of A31
— Options 219, 224, 419, and 423
— Port 1; W81 of A29
— Port 2; W93 of A32
— Port 3; W85 of A30
— Port 4; W89 of A31
2. Using a 5/16-inch torque wrench, disconnect the semirigid cable at the
receiver coupler.
3. Connect the spectrum analyzer to the open receiver coupler connector.
Set the spectrum analyzer to measure a signal at 800 MHz.
4. If the 800 MHz signal is not present and the analyzer has mechanical
switches, continue testing at “Checking the A50, A51, A52, and A53
Mechanical Switches” on page 4-45 .
5. 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 A29 –A32 Receiver Couplers and Receiver Coupler
Mounting Brackets” on page 7-41 .
6. 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 A38, A39, A40, and A41 60-dB Source Step
Attenuators” on page 4-44
7. 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 A33–A36 Test Port Couplers” on page 7-43 .
Checking the A38, A39, A40, and A41 60-dB Source Step Attenuators
1. Locate the appropriate semirigid cable at the output of the source step
attenuator to be checked:
— Options 219, 224, 419, and 423