TeeJet LH665 VRT - Manual (Page 54)

DGPS LH 665 VRT O PERATORS MANUAL
9.4 LH A GRO
Differential Status:
ON or OFF shows whether differential signals are being received or not.
Beacon/Sat. Frequency:
Displays the frequency that differential signals are being received from when
beacon or geo-stationary differential receivers are used.
Differential SNR:
The Signal to Noise Ratio shows the strength of the differential signal in relation to
background interference. A suitable SNR is between 10 to 18 (the higher the
better).
HDOP/PDOP:
HDOP expresses the quality of the horizontal GPS position. PDOP expresses the
distance between the satellites signals are being received from. When the
satellites are close to each other the PDOP value will be high and the positional
data is not as accurate as a low PDOP.
Receiver Voltage:
If this shows 5 volts or higher then the antenna is not connected to the DGPS
receiver (only if an ADD-ON GPS module is fitted). When the antenna is fitted
correctly 0.5 or less is displayed.
RAW NMEA
Step Key Procedure
1
RAW NMEA
The following screen is displayed when the RAW NMEA key
is pressed:
NMEA DIAGNOSTICS DG
Valid GGA and VTG strings…
$GPGGA, 162021.00, 4849.91914,N, 01112.1394
$GPVTG, 178,T,178, M, 006.46, N, 011.97, K*44
EXIT
The NMEA strings are not shown if an ADD-ON GPS module
is connected.