Clear Gtrek; Position - GTrek II User Manual

Errors can occur when downloading data from your GTrek especially if your PC is short of memory
(see recommended PC configuration) or many other applications are also running. In this event it is
possible for data records to be lost, if there are only one or two then these can be ignored. Before
clearing down the GTrek memory try again after closing other
programs.

3.7.1 Clear GTrek

Either from the completion of the data Download sequence or when
selected from the Download dialog the user is given the option to
erase the data stored on GTrek data logger.
Selecting Cancel will leave the data intact and any additional data
will be added until the memory is full at which point logging will
cease.
Selecting OK will start the memory initialization sequence. This
process can take up to 26 seconds.
An elapsed timer is displayed indicating process time. When the
process completes the dialog box will be deleted automatically.
If your GTrek battery is in an extremely discharged state it is
advisable to charge the battery for 15 to 20 minutes before starting
this process.

4. Position

GPS status and positional data is shown here. Latitude and longitude are shown in degrees and
minutes to four decimal places.
Universal Co-ordinate Time (UTC) is equivalent to GMT or BST -1 hour. Speed is in km/h and course
is degrees from true North. Altitude is in meters above
mean sea level as measured by the WGS84 standard.
This standard determines that the earth is a pole-
flattened (oblate) spheroid where the North/South
radius is approximately 21Km less than the equator.
The satellite data received provides information from
which position can be calculated. Three good signals
are required for a 2D Fix and four are required for a 3D
fix. PDOP, HDOP and VDOP are indications of the
Dilution of Positional information representing probable
errors in the data.
The image in the centre is of a representation of the
visible sky from horizon to horizon and indicates the
position of all visible satellites and their allocated numbers. Blue circles indicate satellites which are
providing reliable data. The vertical bar graph below indicates the satellites signal strength.
Reset GTrek, for GPS to work the receiver needs to have to hand detailed information on each
satellite in view, this data is stored on your GTrek and updated during the normal course of operation.
If your GTrek is switch on some distance away (over a 100 miles) from where it was switched off then
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