WILLTEK 4400 Mobile Phone Tester Series, Руководство пользователя

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Chapter 3 GSM Asynchronous Mode Operation
Spectrum measurements
156
4460 GSM System Option and 4468 EDGE System Option Version 12.20
Display markers
The 4400 offers two markers for easy reading of the graphic spectrum displays:
Modulation spectrum
measurement
On the kHz entry fields, you set the markers to the required horizontal positions
(= offset from the carrier in kHz).
The corresponding result fields (
dBm
) show the measurement values obtained for
the two positions in dBm.
The third row shows the difference between the selected frequencies and the
difference between the two corresponding measurement values.
ACPM modulation spectrum
measurement
On the
MHz
selection fields, you set the markers to the required horizontal posi-
tions (= offset from the carrier in MHz).
The corresponding result fields (
dBc
) show the measurement values obtained for
the two positions relative to the RF power level of the carrier.
The third row shows the difference between the selected frequencies and the
difference between the two corresponding measurement values.
To freeze the current display for further or detailed analysis
(or for printing), push this softkey.
The softkey will change to
|Unfreeze|
.
Note: After the
|Freeze|
softkey has been pushed, all mea-
surements (and any ongoing peak-hold process) continue in
the background, but the display is not updated.
This means that even when the live display has been frozen, a
reset of the peak-hold process is possible, pushing the
|Reset|
softkey.
To unfreeze the current display, push this softkey.
The softkey will change to
|Freeze|
.
A push on this softkey resets the peak-hold process of the
“ACPM transient spectrum measurements” .