Leica Builder T User Manual page 62

Configuration Mode
Field Option
Builder
Description
The key beep is an acoustic signal after each keystroke.
The sector beep is an acoustic signal which sounds if
horizontal angle is 0°, 90°, 180°, 270° or 0, 100, 200,
300 gon.
The sector beep is useful for staking out right
angles.
Example for sector beep:
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