HP 8712C, User Manual, Page: 256 / 559

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Calibrating for Increased Measurement
Accuracy
Choose an Appropriate Calibration Method
A reflection calibration removes systematic directivity, source match and
frequency response errors. This type of calibration is also for narrowband
measurements only.
For an example of performing a reflection calibration for a transmission
measurement refer to “Measuring Reflection Response” in Chapter 3.
Otherwise, follow these general steps when performing a transmission
calibration:
1. Setup the analyzer for your measurement:
l
select or
l
enter operating parameters other than the default
2. Press and then one of the following softkeys:
Restoring the default calibration recalls error correction arrays that the
network analyzer previously generated by an adjustment test and stored
permanently in memory. This calibration was performed at the factory or
during servicing using full band (entire frequency span) and 401 frequency
points. It is quick and convenient but not as accurate at narrow frequency
spans. This calibration is also known as the default calibration.
A one-port calibration prompts you to connect three measurement standards:
an open, a short, and a load. The analyzer measures each standard across
the frequency band you have
using the number of points you have
defined. The measurements of these standards are used to remove systematic
errors caused by directivity, source match, and frequency response.
Reflection Calibration
Interpolation
Widening the frequency span after performing this calibration will invalidate
it, and restore the default calibration. You may narrow the span and the
analyzer will interpolate correction for the narrower span.
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