Keysight N5227A Service Manual page 108

Troubleshooting
Measurement System Troubleshooting
Equipment Used for These Tests
Equipment Type
Spectrum analyzer
a. Must be capable of measuring a signal at 1 GHz.
To determine which assembly is defective, check the signal at each available measurement point in the
signal path from the output of the source board to the output port.
Set the network analyzer for an S
frequency of 800 MHz.
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
5. If the 800 MHz signal is not present and the analyzer does not have mechanical switches, replace the
receiver coupler. Refer to
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 receiver coupler and continue testing at
Step Attenuators" on page 4-39
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
4-38
Model or 
Part Number
8565E
S S or S measurement for Port 1, 2, 3, or 4 respectively, with a CW
11, 22, 33, 44,
"Removing and Replacing the A29 –A32 Receiver Couplers and Receiver
7-32.
"Removing and Replacing the A33–A36 Test Port Couplers" on page
PNA Series Microwave Network Analyzers
Alternate Model or Part
Number
a
856xE
4-39.
"Checking the A38, A39, A40, and A41 60-dB Source
N5227A
7-34.
Service Guide N5227-90001