Keysight N5224B, Руководство по обслуживанию

Страница: 134 / 614

4-50 Keysight N5224B/25B Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
— “Bottom RF Cables, 4-Port, Option 420 (Ports 3 and 4), S/N Prefix <6021”
on page 6-198
Trace loss in the signal separation group is due to one or more of the following
assemblies being defective:
— A29, A30, A31, or A32 receiver coupler
— A38, A39, A40, or A41 source step attenuator
— A42, A43, A44, or A45 bias tee
— A33, A34, A35, and A36 test port coupler
— A71, A72, A73, and A74 bias tee combiners
Equipment Used for These Tests
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
11, S22, S33, or S44,
measurement for Port 1, 2,
3, or 4 respectively, with a CW 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 and 419
— 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.
Equipment Type Model or
Part Number
Alternate Model or Part
Number
Spectrum analyzer 8565E
856xE
a
a. Must be capable of measuring a signal at 1 GHz.