Agilent Technologies 85052C, User'S And Service Manual

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3-4 85052C
Use, Maintenance, and Care of the Devices
Cleaning Connectors
Inspect Female Connectors
Inspect the contact fingers in the female center conductor carefully. These can be bent or
broken, and damage to them is not always easy to see. A connector with damaged contact
fingers will not make good electrical contact and must be replaced.
NOTE This is particularly important when mating nonprecision to precision devices.
The female 3.5 mm connectors in this calibration kit are metrology-grade, precision
slotless connectors (PSC). Precision slotless connectors are used to improve accuracy. With
PSCs on test ports and standards, the accuracy achieved when measuring at 50 dB return
loss levels is comparable to using conventional slotted connectors measuring devices
having only 30 dB return loss. This represents an accuracy improvement of about 10 times.
Conventional female center conductors are slotted and, when mated, are flared by the
male pin. Because physical dimensions determine connector impedance, this change in
physical dimension affects electrical performance, making it very difficult to perform
precision measurements with conventional slotted connectors.
The precision slotted connector was developed to eliminate this problem. The PSC has a
center conductor with a solid cylindrical shell, the outside diameter of which does not
change when mated. Instead, this center conductor has an internal contact that flexes to
accept the male pin.
Cleaning Connectors
Clean connectors are essential for ensuring the integrity of RF and microwave coaxial
connections.
1. Use Compressed Air or Nitrogen
WARNING Always use protective eyewear when using compressed air or
nitrogen.
Use compressed air (or nitrogen) to loosen particles on the connector mating plane
surfaces. Clean air cannot damage a connector or leave particles or residues behind.
You can use any source of clean, dry, low-pressure compressed air or nitrogen that has
an effective oil-vapor filter and liquid condensation trap placed just before the outlet
hose.
Ground the hose nozzle to prevent electrostatic discharge, and set the air pressure to
less than 414 kPa (60 psi) to control the velocity of the air stream. High-velocity streams
of compressed air can cause electrostatic effects when directed into a connector. These
electrostatic effects can damage the device. Refer to
“Electrostatic Discharge” earlier in
this chapter for additional information.