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Calibration Details

Kn=value

Performs soft adjustment of sensor and calculated functions, to improve the accuracy of the system Some of these commands override interface cal screws, for convenience sake. The argument <n> identifies the calibration to change, and <value> is the new value for that calibration.

K calibrations are maintained by battery backup. For maximum reliability,
set the calibrations into the screw cals after establishing what they should be.
How to do this is covered in the manual.
DeWiggler includes an audible helper tool.

Boatspeed Master

K1=0.5 to 1.5
Calibrates boatspeed on both tacks equally. When issued, the cal screw on the boatspeed interface is disabled.
  • Readout of Cal Boatspeed Master is on tag 'I'.
  • T1 Status1 displays Cal Boatspeed Master on K1:
  • Autocal will modify this function if enabled.
  • To restore the screw cal, issue K1=D

Boatspeed Offset

K2=-0.125 to 0.125
Calibrates boatspeed differentially on opposite tacks. A positive value increases port tack and reduces starboard tack by the same percentage. When issued, the cal screw on the boatspeed interface is disabled.
  • Readout of Cal Boatspeed Offset is on tag 'i'.
  • T1 Status1 displays Cal Boatspeed Master on K2:
  • To restore the screw cal, issue K2=D

Leeway

K3=0.0 to 16.0
Used to calculate Leeway. Leeway = -K3 * Heel / Boatspeed2
When issued, the cal screw on the boatspeed interface is disabled.
  • Readout of Cal Leeway is on tag 'K'.
  • T1 Status1 displays Leeway Master on K3:
  • To restore the screw cal, issue K3=D

Apparent wind angle offset

K4=-16.0 to 16.0
Calibrates the apparent wind zero. When issued, the cal screw on the boatspeed interface is disabled.
  • Readout of Cal Windangle Offset is on tag 'J'.
  • T1 Status1 displays Cal Windangle Offset on K4:
  • To restore the screw cal, issue K4=D

Apparent windspeed

K5=0.5 to 1.5
Calibrates apparent windspeed. When issued, the cal screw on the masthead interface is disabled.
  • Readout of Cal Windspeed is on tag 'j'.
  • T1 Status1 displays Cal Windspeed on K5:
  • Autocal will modify this function if enabled.
  • To restore the screw cal, issue K5=D

Upwash

K6=-16.0 to 16.0 (Cal Upwash)
K9=0.00 to 0.350 (Cal Upwash Slope)
Upwash modifies apparent windangle to cancel the bending effect sails have on the wind near the mast. These calibrations are modified by the 'Hazen rolloff function' which is has a value of 1.0 at |30| and reduces to near zero downwind.
Upwash = (K6 + K9 * Min(Vt,35) - 12) * Sign(Ba) * Sin2.5(0.6 * (180 - |Ba|)) * Reef2 * Flat
where Reef and Flat are Options 5 and 6 respectively.
  • Readout of Cal Upwash is on tag 'k', Slope on tag "k'".
  • T1 Status1 displays Cal Upwash on K6:, Slope on K9:.
  • Autocal will modify this function if enabled.
  • To restore the screw cal, issue K5=D or K9=D.

Magnetic variation

K7=-50 to 50
Overrides GPS magnetic variation. When issued, GPS magnetic variation is disabled.
  • Readout of Magnetic Variation is on tag 'o'.
  • T1 Status1 displays Magnetic Variation on K7:
  • To restore the GPS magnetic variation, issue K7=D

Polar & Target

K8=0.5 to 1.5
Calibrates polar and target values.
  • Polar calibration does not have a readout of its own.
  • T1 Status1 displays Polar Calibration on K8:

Apparent windspeed offset

K10=0.0 to 1.0
Overrides the programmed windspeed offset, set by the signature switch on the masthead interface.
  • AW speed offset does not have a readout of its own.
  • T1 Status1 displays Polar Calibration on K10:

KwikCal™

K11=±degrees (Upwind KwikCal angle)
K12=±degrees (Downwind KwikCal angle)
K13=±knots (Upwind KwikCal speed)
K14=±knots (Downwind KwikCal speed)
For angle, these commands override the control-code incremental adjustments. For speed, these commands provide the only means of change.

T1 Depth

K15=feet (Transducer depth)
K16=feet (Keel depth)
Since the T1 has no cal screws, when depth is input via the NMEA port, these commands set parameters allowing display of surface and keel depth.
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