Product specifications

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The other information shown includes:
• the Velocity (Speed and Direction)
• the Position (Latitude and Longitude) except that altitude is
missing.
The rest of the text is concerned with the quality of the fix itself.
The Status reports that the GPS has a 3D solution which means it
is computing a solution in all three axes which requires at least 4
satellites.
In addition it is showing a HDOP, Horizontal Dilution of
Position and a PDOP (Point DOP). Dilution of Position is a
unitless number that represents how good the solution is based on the current satellite positions.
For horizontal DOP any number less than 2.0 is very good.
PDOP provides a number that includes both horizontal and vertical accuracy and 3.0 as shown
above is a good number for this. This computation is based strictly on the arrangement of
satellites as shown on the screen. Numbers above 6.0 would indicate a poor arrangement that
might not lead to very accurate results.
The bar chart at the bottom of the screen shows the S/N ratio of each satellite (signal strength)
and the blue bar indicates the satellites that are contributing to the current solution. The numbers
at the bottom of the bar are the same numbers as the one on the map so that the two charts can
be tied together. The receiver is getting a signal from satellite 6 but does not have the data yet to
use it as part of the solution.
By the way, the map of the earth shown on the upper chart is bogus since the satellite view is
looking up, not down with the center of the circle representing the current location and North at
the top. The map itself is only a graphic and provides only misinformation but looks nice.
TrafficWatch and Weather Underground
There is a copy of TrafficWatch and Weather from Weather Underground already built in to
your WayPoint
tm
PDA. These are trial executables that can be used to explore this subscription
service. You will need to subscribe to continue to use these applications. WayPoint 200 owners
have a free year’s subscription to this service.
The data is provided via an internet connection from a Mobile Crossing server. If you are hooked
to a computer via ActiveSync you can take advantage of the computer’s internet link to provide
this data. It is also possible to use a direct internet connection via a LAN card or even a cell
phone providing real time data while traveling. After the data has been collected it can be
displayed even if you are off line.
• TrafficWatch provides live traffic data for selected cities. This includes freeway speed
information and data about potential bottle necks.