IMPORTANT
The first time that the unit is used, it may take up to 10–15 minutes to fully acquire satellites. After this, it will
usually take 1–2 minutes to acquire satellites.
Antenna Placement
Placement of the GNSS antenna is crucial to the quality of the data recorded by VBOX Sigma. Any metal close to a
GNSS antenna can disturb the signal in an unpredictable way due to interference from reflections of weak
GNSS signals.
For the best results, use the antenna in the centre of a metal roof at least 5 cm away from any roof bars or radio
antennas. Do not mount the antenna close to the edge of the roof as reflections from the ground may interfere with the
signals. Avoid the edges as reflections from the A-pillars will cause problems.
Mount the antenna as high up as possible and keep above any roll bars. Pieces of metal close to and above an antenna
will badly disrupt the GNSS signal.
If the vehicle being used does not have a metal roof, then place the GNSS antenna on a flat piece of metal at least 10
cm in diameter. If this is not possible, copper or aluminium foil can be used to create a shaped ground plane underneath
the antenna. For example, on a fibreglass roof, mount the antenna on top of the roof, and place some adhesive backed
metal foil underneath, on the inside of the roof.
https://en.racelogic.support//Product_Info/VBOX_Data_Loggers/VBOX_Sigma/VBOX_Sigma_User_Guide/03_-
_VBOX_Sigma_Getting_Started
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