Keysight Technologies 85055A, Руководство пользователя и сервисное руководство

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1-4 Keysight 85055A User’s and Service Guide
General Information
Precision Slotless Connectors
1-
Precision Slotless Connectors
The female type-N connectors in this verification 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 Keysight Technologies 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
Ω
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.