Keysight FieldFox B Series User Manual page 522

Direction Finding (Option 390 Time Difference of Arrival (TDoA)) – Requires Spectrum
Analyzer Mode (Option 233), and GPS Receiver (Option 307)
Troubleshooting
Troubleshooting
GPS lock Errors
— GNSS receiver must be locked for a successful test, but it may take some
— The following error message is displayed when the GNSS receiver is
Figure 17-1 GPS Error Messages
522
time to achieve lock condition. Allow enough time for the GNSS receivers to
achieve lock after activating them on all FieldFox units.
unlocked.
Possible solutions:
— Running the test again after this error is usually successful because
the GNSS receiver would have enough time to lock.
— Alternatively, check the GPS state directly on each FieldFox unit
before proceeding with the test.
Keysight N9938-90006 User's Guide