Chapter 4 — Troubleshooting
4-6 Troubleshooting
Directivity and Test Port Match Failure
MN469xC Series Multiport Test Set MM
PN: 10410-00730 Rev. D
4-5
4-6
Troubleshooting
Directivity and Test Port Match Failure
This section provides the test procedures to isolate the cause of failure when the test set fails either the
directivity and test port match tests. Refer to
Section 3-6 “Directivity and Test Port Match Verification”
above for VNA setup information.
Equipment Required for VNA System with MN4694C
•
Calibration Kit, K Connector, Anritsu Model 3652A
•
Phase Equal Adapter, K(m) to K(f) Anritsu Model 33KKF50B (Qty 2)
•
Air Line, K Connector, Anritsu Model T2023-2
•
20 dB Offset Termination, K(f) Connector, Anritsu Model SC4808
Equipment Required for VNA System with MN4697C
•
Calibration Kit, V Connector, Anritsu Model 3654D
•
Phase Equal Adapter, V(m) to V(f) Anritsu Model 33VVF50C (Qty 2)
•
Air Line, V Connector, Anritsu Model T2025-2
•
20 dB Offset Termination, V(f) Connector, Anritsu Model SC5727
Directivity Failure Troubleshooting Procedure
1.
Use a different Termination from the Calibration Kit to perform an One Port Cal on Port 1 of the
VectorStar Multiport VNA System.
2.
Verify if the system passes the directivity test.
3.
If the system passes, the cause of the failure is caused by a defective termination in the Calibration Kit.
4.
If the system fails, do the following:
a.
Separate the test set from the 2-port VectorStar VNA.
b.
Re-install the front panel and rear panel loop cables to the VectorStar VNA.
c.
Perform an One Port Cal on Port 1 of the VectorStar VNA.
d.
Verify that directivity of 2-port VNA configuration are the same as those of 4-port VNA
configuration.
e.
If yes, the failure is caused by the termination in the calibration kit.
f.
If no, replace the respective b Channel RF Switch (Low Band Switch or High Band SPDT Switch,
depending on frequencies that the failure occurs).
Test Port Match Failure Troubleshooting Procedure
1.
Separate the test set from the 2-Port VectorStar VNA.
2.
Re-install the front panel and rear panel loop cables to the VectorStar VNA.
3.
Perform an One Port Cal on Port 1 of the VectorStar VNA.
4.
Verify that test port match of 2-port VNA configuration are the same as those of 4-port VNA
configuration.
5.
If yes, the failure is caused by the Open and Short in calibration kit.
6.
If no, do the following:
a.
Replace the Diplexer.
b.
Replace the respective Source Channel RF Switch.