Anritsu MS2722C, User Manual

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Setting Up GPS (Option 31)
6-2 PN: 10580-00277 Rev. E Spectrum Master UG
6. When the GPS receiver is tracking at least 3 satellites, the GPS icon changes to green.
After GPS location Fix is attained, the internal reference oscillator begins to correct its
frequency to match the GPS standard. After the internal frequency is adjusted to match the
GPS standard, the status is indicated by “GPS High Accuracy” showing in the Status menu,
which is displayed on the left side of the measurement display. When the GPS feature is not
enabled, the reference source displays either “Internal Standard Accuracy” or a user-selected
external reference frequency in the Status menu.
Within three minutes of satellite acquisition, the reference oscillator will have an accuracy of
better than 25 ppb (parts per billion). The OCXO internal standard accuracy is ±0.3 PPM.
The correction factor applied to the internal OCXO allows the instrument to maintain GPS
frequency accuracy for three days at better than 50 ppb, even when the instrument is
obstructed from receiving signals from the GPS satellites.
In order to acquire data from the GPS satellites, you must have line-of-sight to the satellites,
or the antenna must be placed outside with no obstructions.
Option 31 requires a GPS antenna, Anritsu part number 2000-1528-R.
Figure 6-2. GPS Icon, Green
Note
As long as 3 minutes may be required for the Ref Freq status to change to GPS
High Accuracy in the Status menu, which is displayed on the left side of the
measurement display.
To reset the GPS, press the Reset submenu key. The green GPS icon with a red
cross appears when GPS satellite tracking is lost (refer to
Figure 6-3 ). This occurs
after being active (tracking three or more satellites).
Figure 6-3. GPS Icon, Green with Red Cross