Displays
Following are details on the various displays.
Speed
Speed is calculated by the GPS unit by measuring the Doppler shift in GPS signals. Speed is displayed in
Knots (Nautical Miles per Hour).
Heading
Course Over Ground (COG), or GPS Heading, is calculated by the GPS unit by measuring the Doppler shift
in GPS signals.
In firmware version 1, your COG is displayed in degrees True. Degrees True is referenced to true north.
The SpeedPuck displays heading only when your speed is greater than 0.5 knot, otherwise it will show a
heading of “- - -“ degrees regardless of which direction you are actually moving.
The difference of the SpeedPuck to a conventional magnetic compass is that the SpeedPuck measures
the direction the device is moving in rather than the direction it is pointed in. A major benefit of the
SpeedPuck over a conventional magnetic compass is that it will give you accurate heading information,
regardless of the orientation in which it is mounted on your boat. SpeedPuck 's compass reading
depends only on the direction you are moving, not the direction the device is pointing.
Max Speed
Instantaneous max speed displayed is a best two second average. Using the SpeedPuck’s high-speed, 18
Hz, GPS module.
The max speed is stored on a session-by-session basis and it is reset when the SpeedPuck is turned off.
Lift/Header Bar Graph Indicator
The SpeedPuck automatically detects when a sailor is trimmed to a heading then provides the header/lift
indication. When the device detects that the sailor is trimmed at a heading the trim angle is set. Then
header/lift indication is given off of that trim angle. Once a tack or a jibe is detected the indicator
resets and nothing is indicated until another trim angle is set. Each bar segment represents 3 degrees
of wind shift.
