Pentax W-1502N Series Instruction Manual page 57

Operation steps
①Under
distance
measurement,
"MLM" key to activate
Missing
Measurement.
②Select method (A-B,
A-C) with stylus.
③Collimate
A,click "M.Dist"
Horizontal distance
between instrument and
prism A will be shown.
Keys
click
【MLM】
Line
prism
key.
【M.Dist】
Display
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