N5511A Phase Noise Test System User’s Guide 359Preventive MaintenanceUsing, Inspecting, and Cleaning RF Connectors— Never bend a cable at a sharp angle.— Do not bend cables near the connectors.— If any of the cables will be flexed repeatedly, buy a back-up cable. This willallow immediate replacement and will minimize system down time.Before connecting the cables to any device:— Check all connectors for wear or dirt.— When making the connection, torque the connector to the proper value.Proper Connector Torque— Provides more accurate measurements— Keeps moisture out of the connectors— Eliminates radio frequency interference (RFI) from affecting yourmeasurementsThe torque required depends on the type of connector. Refer to Table 19-1. Donot overtighten the connector.Never exceed the recommended torque when attaching cables.Connector Wear and DamageLook for metal particles from the connector threads and other signs of wear(such as discoloration or roughness). Visible wear can affect measurementaccuracy and repeatability. Discard or repair any device with a damagedconnector. A bad connector can ruin a good connector on the first mating. Amagnifying glass or jeweler’s loupe is useful during inspection.2.92 Connector Precautions2.92 connectors are used on the front RF In connector on the test set. Theseconnectors can be used with 2.92 mm and 3.5 mm connectors.Table 19-1 Proper Connector TorqueConnector Torque cm-kg Torque N-cm Torque in-lbs Wrench P/NType-N 52 508 45 hand tighten3.5 mm 9.2 90 8 8710-1765
