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8. Offset Mode
Offset function is designed to obtain coordinate information
of the measured point when prism cannot be place at the
measured point or when distance measuring cannot be done. It
includes five functions which are Angle Offset, Single/ Double-
distance Offset, Plane Offset and Column Offset.
Before operating these functions, please set „STA‟ ,
orientation, instrument height and target height firstly.
Mention that when selecting any measurement mode
including repeated, continue or tracking mode (beside single
mode) for offset , you must first press the key „ESC‟ to stop
measuring before any followed operations.
8.1 Angle Offset Mode
This mode is specifically useful when setting up prism
difficultly ,e.g. in the center of a tree. Set up the prism at the point
„P‟ which is the same horizontal distance away from the
instrument .The diagram for angle offset is as followed.
When measuring the coordinate of the earth point„A1‟
which is the projection of „AO‟, set up the height of instrument
and the height of target.
When measuring the coordinate of „AO‟, set up the height of
instrument only (and the height of target should be set to 0). Enter
the page „1.Offset (Angle)‟ which is as followed:
