Keysight E6640A, Руководство пользователя и программиста по приложениям измерений

Страница: 212 / 2870

4 Input/Output Functions
Input/Output
correction for all amplitude corrections which are currently on, although the total, accumulated correction
for all corrections which are turned on is still applied to the data traces.
Because corrections data is always in dB, but the Y-axis of the analyzer is in absolute units, it is necessary
to establish a reference line for display of the Corrections data. The reference line is halfway up the display
and represents 0 dB of correction. It is labeled “0 dB CORREC”. It is drawn in blue.
Corrections data is always in dB. Whatever dB value appears in the correction table represents the
correction to be applied to that trace at that frequency. So if a table entry shows 30 dB that means we ADD
30 dB to each trace to correct it before displaying it. By definition all points are connected. If a gap is
desired for corrections data, enter 0 dB.
Note that a well-designed Corrections array should start at 0 dB and end at 0 dB. This is because whatever
the high end point is will be extended to the top frequency of the instrument, and whatever the low end
point is will be extended down to 0 Hz. So for a Corrections array to have no effect outside its range, you
should start and end the array at 0 dB.
The table editor will only operate properly if the analyzer is sweeping, because its updates are tied to the
sweep system. Thus, you should not try to use the editor in single sweep, and it will be sluggish during
compute-intensive operations like narrow-span FFT sweeps.
When exiting the edit menu (by using the Return key or by pressing an instrument front-panel key), the
editor window turns off and the Ampcor trace is no longer displayed; however, Apply Corrections remains
On, any correction that was on while in the editor remains on, and the amplitude scale returns to its
previous setting.
Corrections arrays are not affected by a Preset, because they are in the Input/Output system. They also
survive shutdown and restarting of the analyzer application, which means they will survive a power cycle.
When editing a correction, the editor remembers which correction and which element in the correction
array you were editing, and returns you to that correction and that element when you return to the editor
after leaving it.
Key Path
Input/Output, Corrections
Initial S/W Revision A.02.00
Navigate
Lets you move through the table to edit the desired point.
Key Path
Input/Output, Corrections, Edit
Notes There is no value readback on the key
Min 1
Max 2000
Initial S/W Revision A.02.00
212 W-CDMA & HSPA Measurement Applications Reference