NARDA 8718B, Руководство пользователя

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25 Chapter 4 Making a Measurement
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When there are multiple emitters with frequencies that
are close to each other and the nearest calibration
frequencies have very similar correction factors.
Correction factors should NOT be used:
•
When the frequencies of the emitters are diverse.
Correction factors may vary considerably and there is no
way to determine the distribution of energy from the
various emitters. It is more accurate not to use a
correction factor under these conditions. See
Measurement Uncertainty on page 27.
To use a correction factor for a probe in memory...
1. Press F4 ( FREQ ) from the measurement screen. A
new screen will appear to allow you to enter a
frequency.
2. Enter the frequency for which you want to correct
readings. Make sure you fill in all four positions. If you
make a mistake just enter more digits until correct. For
greater accuracy, use the units that allow the larger
numbers. For example, enter 10kHz, not 00.01 MHz.
3. Change the units (if needed) by pressing either
F1 ( kHz ), F2 ( MHz ), or F3 ( GHz ).
4. Press F4 ( SAVE ). The meter will automatically
calculate the correction factor for the frequency you
have entered from the two closest correction factors
that were stored when you put the probe in memory.
The calculated numeric value will be displayed briefly
before the meter automatically returns to the
measurement screen. See page 64 for a more
complete description.
5. The frequency that you are correcting for will be
displayed on the right side of the third line of the
display.
Do not use correction
factors in a broadband,
multi-emitter environ-
ment.
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