Keysight Technologies 85054B, Руководство пользователя и сервисное руководство

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General Information
Precision Slotless Connectors
Precision Slotless Connectors
The female type-N connectors in this calibration kit are metrology-grade, precision slotless
connectors (PSC). A characteristic of metrology-grade connectors is direct traceability to
national measurement standards through their well-defined mechanical dimensions.
Conventional female center conductors are slotted. When mated, the female center conductor
is flared by the male pin. Because physical dimensions determine connector impedance,
electrical characteristics of the female connector (and connection pair) are dependent upon the
mechanical dimensions of the male pin. While connectors are used in pairs, their male and
female halves are always specified separately as part of a standard, instrument, or device
under test. Because of these facts, making precision measurements with the conventional
slotted connector is very difficult, and establishing a direct traceability path to primary
dimensional standards is nearly impossible.
The precision slotless connector was developed to eliminate these problems. All PSCs are
female. A PSC incorporates a center conductor with a solid cylindrical shell that defines the
outside diameter of the female center pin. Its outside diameter and, therefore, the impedance in
its region does not change. The inner part provides an internal contact that flexes to accept the
allowed range of male pin diameters.
The calibration of a network analyzer having a conventional slotted female connector on the
test port remains valid only when the device under test and all calibration standards have
identical male pin diameters. For this reason PSC test port adapters are supplied in most
calibration kits.
Precision slotless connectors have the following characteristics:
• There is no loss of traceable calibration on test ports when the male pin diameter of the
connector on the device under test is different from the male pin diameter of the calibration
standard.
• The female PSC and its mating male connector can be measured and specified separately
as part of the device either is attached to.
• All female connectors can have a known, stable impedance based only on the diameters of
their inner and outer conductors.
• Female calibration standards can be fully specified. Their specifications and traceability are
unaffected by the diameter of the male mating pin.
• A fully traceable performance verification is made using a precision 50 ohm airline having a
PSC.
• Measurement repeatability is enhanced due to non-changing connector characteristics with
various pin diameters.
With PSCs on test ports and standards, the percentage of 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.