User's Manual Part 3

GeoExplorer 2008 Series User Guide 121
Troubleshooting 7
GPS receiver issues
Problem Cause Solution
The handheld is not
receiving GPS positions.
The integrated GPS
receiver is not activated.
Use the Connect or Activate GPS command in the GPS
field software to open the GPS COM port and activate
the integrated GPS receiver. For more information, see
Using the GPS receiver, page 61.
Incorrect configuration of
serial COM port.
When supplying GPS data to an external device using
the COM1 serial clip, set the baud rate to the high-
speed TSIP setting: 38400, 8, 1, Odd.
The GPS COM port is
already in use. Only one
application at a time can
have the port open.
Do the following:
• Exit the software that is using the GPS COM port
and then retry in your application.
• Check that a GPS application is not running in the
background. Tap / Settings / Memory, select
Running Programs, and then select and close any
GPS applications you are not using.
• Make sure that connections are not left setup in the
GPS Connector application. Set NMEA to Internal -
COM2 and TSIP to Internal - COM3, and then
disconnect GPS Connector when you not using the
connections.
The GPS field software is
using the wrong GPS COM
port.
Connect to COM2 if the GPS field software uses NMEA
messages, or COM3 for TSIP messages. For information
on which protocol to use, check the documentation for
the application.
Not enough satellites are
visible.
Move to a location where the receiver has a clear view
of the sky and ensure the antenna is not obstructed.
Alternatively, adjust the GPS settings to increase
productivity. For more information, refer to the Help
provided with the GPS field software.
The DOP (Dilution of
Precision) value for the
current position is above
the maximum DOP
setting.
Wait until the DOP value falls below the maximum DOP
specified.
Alternatively, adjust the GPS settings to increase
productivity. For more information, refer to the Help
provided with the GPS field software.
Wait for real-time is
selected in the GPS field
software and the
integrated receiver is
waiting to receive
real-time corrections.
If you are collecting data for postprocessing, clear the
wait for real-time selection.
Check that the real-time correction source is setup
correctly (see Connecting to a real-time differential
correction source, page 68).
External antenna
connected but not
receiving data.
The handheld can take up to two seconds to detect
that an external antenna has been connected or
disconnected.
NMEA data includes
autonomous positions.
The integrated GPS
receiver outputs
autonomous positions
when real-time
corrections are
unavailable.
Configure the NMEA application to filter out non-DGPS
positions.