Geometrics G-877, Operation Manual

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check the Do not enter calibration coefficients now button and the scale will be set as 1 and bias
as 0. Do this if you don’t know calibration coefficients at this time.
Note that this screen will not appear if you do not have depth or altimeter sensors in your system.
Real time lay back calculations.
MagLog has a feature called "Interpolator" which allows you to calculate the position of the
magnetic sensor based on the GPS position and the system geometry in real time. This function
saves time and effort because the final data will be logged in a format ready to be loaded into
many popular programs (like Surfer, for example) with the position of the fish (not the boat) in
the file. In order to use this feature, you will need to know the geometry of the magnetometer
array (boat size, GPS antenna, tow winch locations, the tow cable length) as well as the
geographical position of the survey area. Be ready to enter all these values and the central UTM
meridian if you want this feature enabled.
Hint: If your GPS is reporting correct positions and you "auto detected" it during the GPS
configuration step, the central meridian will be computed and entered automatically.
G–877 MARINE MAGNETOMETER OPERATION MANUAL
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