Anritsu 37 C Series, Operation Manual

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Evaluating the Calibration The 37XXXC provides an accurate representation of complex data.
However, it can only provide accuracy to the extent of the supplied cal-
ibration data. For this reason, it is necessary to periodically verify the
calibration data and the 37XXXC system performance.
Calibration verification reveals problems such as a poor contact with
one of the calibration components, improper torquing, or a test port
out of specification. Problems like these can easily occur during a cali-
bration procedure. Anyone who has experienced one of these problems
and stored bad data—after having performed a complete calibration
procedure—knows the frustration it can cause. Additionally, it can be
very costly to use incorrectly taken measurement data for design or
quality assurance purposes.
The best way to confirm a calibration is to measure a precision,
known-good device and confirm its specifications.
Verification Kits ANRITSU has developed several precision-component kits: for 3.5 mm
connectors, for GPC-7 connectors, K Connectors
â
and V Connectors
â
.
These are, respectively, the Models 3666, 3667, and 3668 and 3669
Verification Kits.
Each of the kits contain 20 dB and 50 dB attenuators, an airline, and a
Beatty Standard. A Beatty Standard is a two-port mismatch similar to
a beadless airline. It consists of a center conductor with a discontinu-
ity in the middle providing the mismatch (Figure 7-7).
Typically, these verification kits will be used by calibration or metrol-
ogy labs. Each of the kits contain several precision components, all of
which have been characterized at specified frequencies. The data on
these components is stored on a disk provided with the verification kit.
The verification of the kit components is straight forward. The compo-
nents are first measured with the 37XXXC, then they are compared
with the data recorded on the disk. If the measured data compares fa-
37XXXC OM 7-11
MEASUREMENT CALIBRATION DISCUSSION
VERIFICATION KIT
Used by Calibration and Metrology
Labs
S
1 1
5 0
9
2 5
9
5 0
9
5 0
9
Figure 7-7. The Beatty Standard