Roos Instruments recommends that the following Preventive Maintenance Procedure be carried out once every twelve months to keep the Cassini System operating at peak performance.
1) Perform the regular (daily) Maintenance: Visually inspect all of the Microwave connectors between the Test Head and Fixture. Look for any physical damage, bent pins or fingers, and contamination such as dirt, metal flakes, etc. Also check the physical interface between the Fixture and Handler for signs of wear.
2) Inspect all the cable connections in the Test Fixture, rack and auxiliary rack if applicable, and check all the 10-pin round RIFL III cable connectors for looseness. If a connection is loose, check the connector for damage and replace if needed.
3) Clean the air filters on the back of all the 20 GHz sources (if applicable).
4) Connect the Diagnostic Fixture to the RI Test Head, make sure it is seated correctly, then press the Fixture downward on to the Test Head and press the Fixture lock button.
5) Perform all of the "System Diagnostic Procedures". If there are any failures, rerun that specific Diagnostic and verify the failure. If you have sufficient resources, replace the most likely defective component and rerun the specific diagnostic.
20 GHz Source Preventative Maintenance and Cleaning procedure
The 20 GHz RF sources have filters on the fans that are located on the rear of the unit, and they require periodic inspection and cleaning. Even in a clean-room environment, the filters can become clogged with dust and debris. If this gets too thick, it can cause the source to run too hot, affecting the performance of the tester.
1) Open the back door of the tester or auxiliary rack, and inspect the fans on all the 20 GHz sources. If there is dust or debris in the filters, proceed to step two.
2) With the system stopped (not running any tests), unplug the AC power cords at the sources to stop the fans.
3) Using a strong vacuum, vacuum the filters. Try to disturb the RF cabling as little as possible, to prevent performance changes in the tester.
Note: NEVER use compressed air to clean the filters. This will embed the dust into the filter.
4) Using a soft-bristle brush, carefully brush dust off the plastic fan shield.
5) Plug the AC power cords back into the sources and perform a 'CHECK' on the system. Starting the sources in this warm condition ( only having been off for short while, causes the internal open heaters to overshoot and you must allow at least 10 minutes for the temperature to stabilize inside the sources before attempting to confirm that the system is operating properly by running a test.
Note: The LEDs on the sources will be red when the source is plugged in. After the system startup, they should be green. This is not an indication of stability, just that they have been programmed and initialized.