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A. Setting instrument up for use
Extend tripod legs to desired length, stamping leg points into
ground. In doing so, see that tripod head is already as
horizontal as possible. Take level out of protective case,
putting it on tripod head. While holding level with one hand,
tighten tripod screw connecting level with tripod head.
B. Levelling instrument
Turn instrument until circular spirit level is in a central
position above two of the three foot screws [10]. Then turn
said two foot screws in opposite directions, until bubble rise
to centre. After that, adjust opposite third, foot screw until
bubble is well within etched circle.
Instrument is ready for taking readings if bubble is well
within etched circles.
D. Correcting circular spirit level
Usually this operation will turn out to be necessary very
seldom. This correction will also be unnecessary if, on the
instrument levelled as per B and turned by 180 degrees,
bubble is slightly out of centre, but still within the etched
circle. If deviation is greater, one should proceed as follows:
Pull off protecting cap of circular spirit level. Level instrument
as per B. Now turn it by 180°. The bubble displacement has
then to be corrected half by the foot screws and half by the
two adjusting screws.
Now and again make sure that compensator is in good
working order, by moving one of the foot screws
slightly. Image must then oscillate back to previous
position.
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C. Adjusting the telescope
Adjust the telescope while it is turned towards a bright
background. Turn eyepiece ring [8] until cross lines appear
sharp. So as not to have to repeat this operation after each
fresh setting-up, remember adjusted number.
For rough sighting levelling staff, use optical sight [6] on
telescope body.
To achieve this, place the eye close to the sight and extend
this white line, which is surrounded by a black field, up to the
target (see picture).
Employ tangent screw [3] to move staff to centre of field of
view. By means of focussing knob [7], image is now made to
appear sharp.
E. Measuring distances
The rod section between the upper and lower cross hair
short lines, given in terms of com, is multiplied by 100 to yield
the distance to the rod in terms of meters.
Example:
upper line:
lower line:
difference:
distance:
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160
136,5
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23,5 cm
23,5 m
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