Giga-tronics 8003, Руководство по эксплуатации

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Operation
Manual 20791, Rev. C, June 2001 2-97
The [ ABSPWR/PATHCAL ] softkey controls whether the analyzer makes a complete ABSolute PoWeR
measurement (including Cal Factor correction), or ratio’s the measurement with a previously stored
PATH CALibration. If it ratio’s with a PATH CALibration, the analyzer will not apply Cal Factor
corrections since the measurement is already a ratio. This characteristic allows you to see the Cal Factor
correction applied to a sweep. Figure 2-54 shows two traces made with the same sensor. The channel 1
trace shows an ABSolute PoWeR measurement with Cal Factor correction. The channel 2 trace shows
exactly the same measurement without Cal Factor correction. As you can see, with Cal Factor
corrections, the analyzer correctly shows the true flatness of the sweeper.
To set up the analyzer to make Absolute Power measurements on a channel, press
[MEAS]
. Toggle the
[ ABSPWR/PATHCAL ] softkey until [ ABSPWR/ ] is in light blue and [ PATHCAL ] is in dim, dark blue.
All measurements will now be fully corrected with Cal Factor corrections, and will be displayed in units
of dBm.
To set up the analyzer to ratio with a path calibration, press
[MEAS]
and toggle the [ ABSPWR/
PATHCAL ] softkey until [ PATHCAL ] is in light blue. Now the analyzer will ratio with the stored path
calibration data, but will not use Cal Factor corrections. All measurements will be relative to the stored
path calibration data and displayed in dB.
Figure 2-54: 8003 Swept Power Measurements with CAL Factor Correction
NOTE:
In either of the above cases, the cursor reads absolute power levels or power ratios
at the selected frequency.
CONT
AUTOSCL
REF
POSN
AUTO-
SCALE
SCALE
FACTOR
SCALE
STRT 2.000 GHz
STOP
SCALE FACTOR
0.1 dB/DIV
CH1: SW C
0.1 dB/
REF -10.03 dBm
CH2: SW C -PC
0.1 dB/
REF 10.03 dB
18.000 GHz
REF
LEVEL
21
CH 1
CH 2
CH1 - WITH CAL FACTORS
CH2 - WITHOUT CAL FACTORS
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