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SL1 DATALOGGER User Manual Rev.AA
ENGLISH
3.1 GPS ANTENNA INSTALLATION
3.2 GPS FIXING
In order to install properly the GPS antenna please refer to the following instructions:
• Be really careful during GPS antenna movement: Avoid shocks and verify that connector and
cable are in a perfect shape
• Fix the antenna outside the vehicle: obstacles near to the antenna could cause a reduction to
the receiving capabilities of the sensor. A wrong position could cause an incorrect lap timing,
wrong data acquisition and wrong trajectories
• Do not twist the antenna cable around other cables (especially around high voltage plugs
wiring): this could cause inductive interferences and cause problems during the functioning
• Let pass the antenna cable as far as possible from spark plugs and other electromagnetic
field. In motorbikes it is preferable to run the cable out of the chassis but in any case in a
protected zone
• Fix the GPS connector to the ANTENNA input in MD40 without use excessive torque: do not
use tools
Some suggestions to fix the antenna:
• Speed bikes: fix the antenna in the far back part of the motorbike away from heat sources
(exhaust) or in cockpit area (on top of it).
• Off-road bike: fix the antenna on handlebar handle pad.
• Car: fix the antenna on top of the roof.
• Kart: fix the antenna on the higher part of front number plate, if needed manufacture a support
to address the sensor in the proper direction.
You need to “fix” satellites in order to get trajectories and lap times in analysis software.
The minimum number of satellites to get a correct acquisition is 5.
In fixed application (e.g. dyno sessions) you do not need GPS.
NOTE: SL1 will continue to search satellites during logging. This permit to start the acquisition
also without GPS data. In this case it will be probable that trajectories visualization (done via
software) could be compromise.
The evidence of this phenomena are fast variations on the position of vehicle (spike), up to
some kilometres!!!!