Sony HKDW-704, Руководство по эксплуатации

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1
Chapter 1 Using GPS Data
1-5
1-2-3 Errors
Errors by the GPS Receiver
This board determines automatically the current location utilizing radio
waves from at least 3 satellites. The error that GPS satellites generate is
about ±10 m. However, depending on circumstances in a given a survey
location, an error of several hundred meters may be generated.
When this board cannot receive radio waves from
satellites
When you are shooting in a location where the board cannot receive
radio waves from satellites such as those listed below, this board may not
be able to determine the correct location.
• Underground
• Among crowded trees
• Under high objects such as bridges
• inside or in the shade of a building
• In a tunnel
• At a multi-level crossing
• Among tall buildings
• On a narrow road among buildings
• near a place where magnetism is generated, like high-voltage cables
• near a place where electromagnetic waves in the same frequency range
as those of satellite are generated, like those from 1.5 GHz portable
communications devices
Note
GPS radio waves are managed by the U. S. Department of Defence.
There may be a case where the Department of Defence changes the
accuracy on purpose.