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During a traverse the data logger will display the current gradiometer readings and the Grid,
traverse and position numbers.
The data logger prompts the operator to start each new traverse. When the last line is
completed, the operator will be prompted to save the Grid or go back one line. If the Save option
is selected then a summary will be displayed showing the mean, minimum and maximum values
together with the battery voltage. The summary values always reflect the measurements of
sensor 1. The ENTER key clears the display and returns to the main menu.
Note: During traverses, maintain the sensors in a vertical position to minimise rotational
errors. If the instrument is tilted in the traverse direction then the data will be biased in
that direction, and a significant stagger may appear between traverses when a zigzag
pattern is used.
18.1. Interrupting a Survey
Dummy values outside the normal range are used to fill the data pattern over inaccessible areas.
When operating in a zigzag pattern, an obstruction may prevent the end of the current traverse
and the start of the next traverse being completed.
Pressing the ESC key at any time during a traverse will halt the data collection process. A menu
will appear offering the following choices:
Menu option Function if selected
Finish and mirror
The remainder of the current traverse is filled with the dummy value
(32702) and an equal number of dummy values are inserted at the
start of the next traverse. Data can then be collected normally for the
remainder of the traverse. If the selected pattern is parallel rather
than zigzag, then the instrument will simply give an audible bleep to
indicate an invalid command.
Finish Grid
The remainder of the Grid is filled with dummy values. The operator
will then be prompted to save the Grid or return to the start of the
last line.
Finish traverse
Inserts dummy values up to the end of the current traverse, and
prompts the operator to start the next traverse. This is used
to complete a line where an obstruction prevents a line being
completed.
Change pace
The current pace is displayed and the operator is prompted to use
the arrow keys and ENTER to set the pace required.
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