Furuno FAR21x7 & BB FAR28x7 Operator's Manual BB FAR28x7 Operator's Manual page 245

7. Press the [F1] key to change the display. The buzzer stops and the screen
shows the sentences being input to the radar, under the categories of GPS1
and GPS2 (position), speed, heading and nav data. Below is an example.
(The sentences shown depend on your system settings.)
<GPS1>
GGA
GLL
RMC
RMB
VTG
ZDA
DTM
BWR
BWC
<GPS2>
GGA
GLL
RMC
RMB
VTG
ZDA
DTM
BWR
BWC
<SPEED>
VBW
VHW
VDR
<HEADING>
HDT
<NAV DATA>
WPL
RTE
MWV
VWT
VWR
DPT
DBT
DBS
MTW
VDM
Sentence input display
8. To terminate the test, press the [F1] key.
6. MAINTENANCE, TROUBLESHOOTING
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