Tektronix NetTek YBT250, Руководство пользователя

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GPS
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YBT250 Field Transmitter & Interference Tester User Manual
Figure 2- 21: The GPS Satellite Signal Strength field
Saving GPS Data with Measurements
The YBT250 automatically saves location, time, and date informa-
tion with measurements whenever the GPS receiver is active and
acquiring accurate location data. For accurate measurement records,
make sure to save or export your results at the location where you
made the test.
If you take a measurement, move the instrument, and then save your
results, you will not be saving the coordinates of where you took the
test. You will be saving the coordinates of your new location.
Troubleshooting Your GPS Receiver
If the application is unable to read position information from the
GPS receiver, then check or do the following:
H
If the message ”Invalid Position” appears, then the communica-
tion connection to the receiver has been successfully established,
and the NMEA sentence is being successfully read from the
receiver, but the position supplied in that sentence is not valid.
An invalid position is normal while the GPS receiver is initially
attempting to locate and receive data from 4 satellites. When the
GPS receiver is first turned on, it typically requires about 90
seconds to lock onto satellites. If the Invalid Position message
lasts longer than a few minutes, check the GPS signal strength
and DOP values.