Power Loss Correction List; Power Sensor Calibration Factor List; Speed And Accuracy; Test Equipment Used - Agilent Technologies 8719D User Manual

Power Loss Correction List

If a directional coupler or power splitter is used to sample the RF power output of the analyzer,
the RF signal going to the power meter may be different than that going to the test device. A
directional coupler will attenuate the RF signal by its specified coupling factor. The difference
in attenuation between the through arm and the coupled arm (coupling factor) must be entered
using the loss/sensor list menu. Non-linearities in either the directional coupler or power
splitter can be corrected in the same way.
Power loss information is entered in much the same way as limit line parameters. Up to 12
segments may be entered, each with a different attenuation value. The entered data will not
be lost if the instrument's power is cycled.

Power Sensor Calibration Factor List

Two power sensor calibration data lists can be created in the analyzer. No single power sensor
covers the entire frequency range of the analyzer, therefore the calibration data for two
different power sensors must be available. The entered data will not be lost if the instrument's
power is cycled.

Speed and Accuracy

The speed and accuracy of a power meter calibration vary depending on the test setup and the
measurement parameters For example, number of points, number of readings, if the power is
less than -20 dBm, continuous versus sample and sweep mode. Accuracy is improved if you
set the source power such that it is approximately correct at the measurement port. Power
meter calibration should then be turned on. With number of readings = 2, very accurate
measurements are achieved.
test setup for continuous correction or for the first sweep of sample-and-sweep correction.
The typical values given in 'lhble 6-7 were derived under the following conditions:
HP 8720D network analyzer
n
HP 436A power meter
n
HP 8485A power sensor
n

Stimulus Parameters

The time required to perform a power meter calibration depends on the source power and
number of points tested. The parameters used to derive the typical values in 'lhble 6-7 are as
follows:
number of points: 51,50 MHz to 20.05 GHz
n
test port power: equal to calibration power
n
Sweep time is linearly proportional to the number of points measured. For example, a sweep
taking 49 seconds at 51 points will take approximately 98 seconds if 101 points are measured.
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