Keysight Technologies N5244/5B Service Manual page 145

Troubleshooting
Measurement System Troubleshooting
5. If the 800 MHz signal is not present and the analyzer does not have
mechanical switches, replace the reference coupler. Refer to
and Replacing the A29–A32 Reference Couplers and Reference Coupler
Mounting Brackets" on page
6. If the 800 MHz signal is present and the analyzer has source attenuators
and bias tees, reconnect the cable to the reference coupler and continue
testing at
Attenuators" on page 4-51
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
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:
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
the A46–A49 Receiver Attenuators" on page
5. If the 800 MHz signal is present, replace the associated bias tee. Refer to
"Removing and Replacing the A38–A41 Source Attenuators and the
A46–A49 Receiver Attenuators" on page
Checking the A50, A51, A52, and A53 Mechanical Switches
1. Locate the appropriate semirigid cable at the output of the mechanical
switch to be checked:
Keysight N5244B/45B Service Guide
"Checking the A38, A39, A40, and A41 60-dB Source Step
— Options 219, 224, 419, and 423
— Port 1; W82 of A38
— Port 2; W94 of A41
— Port 3; W86 of A39
— Port 4; W90 of A36
"Removing and Replacing the A38–A41 Source Attenuators and
— Options 224 and 423
— Port 1; W106 of A50
— Port 2; W120 of A53
7-51.
7-57.
7-57.
"Removing
7-53.
4-51