Nexus RACE BOX, Инструкция по установке и эксплуатации

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English RaceBox
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timer will be started at 5:00.
Viewing the time remaining on the Race Box timer
You can view the time remaining on the Race Box timer in the CFD field by setting the
configuration file like this:
TIMER_CFD=Y
This will cause the time remaining on the Race Box timer to be displayed in the CFD
field. The time will only be displayed until the Nexus network timer is started. After that
point, whatever you have set in CFD_IS will then take over.
If you start the Race Box timer and the Nexus network timer at the same number of
minutes (that is, either 5:00 or 10:00), then the CFD field will never display the Race
Box timer value simply because it will never be running when the network timer is not.
Conversely, if you set TIMER_CFD to Y but you do not use the network timer
(set USE_NEXUS_TIMER to 0) then the Race Box timer will always display the time
remaining during the starting sequence, and the CFD_IS data will never be displayed.
The advantage of this is that you'll be able to sync down right to the last minute.
5 Interpreting the data. What does it all mean?
The algorithms used by the Race Box for start line timing are straightforward, but it is
important to understand what it is doing so that the crew can make the best possible
use of the information presented. This section will explain how the Race Box derives
the numbers it presents.
At the most basic level, the Race Box is calculating your position, speed and heading
relative to that of the starting line. All the data for start line timing calculations comes
from the GPS receiver connected to the Race Box. Because the starting line is
anchored to the ground, the Race Box needs to use ground relative data to do its job.
So, it uses position, course over ground (COG) and speed over ground (SOG) from the
GPS receiver.
The Race Box “targets” a position somewhere along the starting line and calculates the
distance to that position
from your bow along a particular path. For the crew, using the
data effectively requires that you understand both (1) where the target point is and (2)
what the path is to the point being targeted.
5.1 How does the Race Box choose its target?
Imagine a line running along the center of your boat, extending exactly forward and aft
from your mast and that this line extends off the boat, both forward and aft. This line
either intersects the starting line or it does not.
If this line intersects the start line, the the
intercept point of your centerline and the start line is the target. If this line does not
intersect the starting line, then whichever end of the line is closer to the bow becomes
the target.