Tektronix NetTek YBT250, Руководство пользователя

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Taking Measurements
3- 136
YBT250 Field Transmitter & Interference Tester User Manual
below 0.1 dB is desirable, although measurements can be made
above this level. MP values above 0.4 dB indicate that the signal
quality is not adequate for accurate OTA measurements.
When making cdma2000 or 1xEV-DO OTA measurements, the goal
is to find a location that provides both high PD values and low MP
values. It may be necessary to walk or drive around the measurement
site, monitoring the OTA Signal Quality icon until both PD and MP
indicators are green. Once a good location is found, you can take
cdma2000 or 1xEV-DO OTA measurements.
Multiple Measurements Sequencer
On the Sequencer screen (tap button 4), you can view the current
readouts for multiple measurements at the same time. These
measurements include the numeric results that you could otherwise
view one at a time on the Measurement screen (button 1). The
YBT250 application sequences through each of the measurements
that you designate and it summarizes the results on the Sequencer
screen.
To select which measurements to take and display on the Sequencer
screen:
1. Select a signal standard.
2. Tap the Sequencer button.
3. Tap the Select Measurements... button. The Select Measure-
ments dialog box appears. The list of available measurements
depends on the standard you selected.
4.
Select or clear the measurements in the list to display only the
measurements of interest to you.
5. Tap OK . See Figure 3--68.
The Sequencer screen shows each measurement type you selected
(such as RF Power and Carrier Frequency) in a gray bar. Beneath
each measurement type, the measurement readouts are displayed.
As each measurement type is updated, the measurement type
heading is highlighted in reverse video.