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GPS
HOW GPS WORKS
Currently, the GPS constellation consists of 26 orbiting satellites (including 3 spares), but this nu
mber will increase in the future.
The GPS receiver computes an accurate position by calculating the distance to the GPS satellit
es that orbit the earth. Signals are required from 3 satellites for two dimensional (2D) position
calculation whilst 4 satellites are required for three dimensional (3D) position calculation.
As mentioned earlier, GPS satellites are not geostationary, but they are orbiting the earth as illu
strated on the following figure:
[The GPS constellation]
Note that position is repeatedly fixed through the following three steps while any 3 satellites are
in line of sight.
Summary of Contents for HD-1000C
Page 8: ... 8 ...
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Page 15: ... 15 2 Specification of the connectors 2 1 Metal connectors ...
Page 16: ... 16 2 2 Plastic connectors ...
Page 19: ... 19 3 3 Navigation Data page 3 3 1 Navigation Data Type1 3 3 2 Navigation Data Type2 ...
Page 34: ... 34 10 Memory Card Inserting the SD micro SD USB OTG as Fig 1 7 1 Fig 1 7 1 ...
Page 39: ... 39 ...
Page 46: ... 46 2 9 Move to vessel Call the cursor and move the WPT and Enter Choose Move to vessel ...
Page 47: ... 47 2 10 Sorting MENU Userdata WPT List 4 Sort Sorting the order of WPT on the list ...
Page 57: ... 57 Long press where you want to start erasing the track 1 should show on the left top ...
Page 74: ... 74 2 2 Detail Choose the AIS target and press ENTER ...
Page 75: ... 75 2 3 Goto Choose the AIS target and press 4 Find ...
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