7
Angle measurement
To measure the angle, aim the vertical line of the reticle at target A and read α on the
graduated scale of the horizontal circle. Aim at target B and read β on the dial. As a result,
the sought angle between A and B will be equal to the value of α-β (see Fig. 8).
Fig. 8
6. Checking and adjusting
We make sure that all levels are fully adjusted and ready for use, but nevertheless, the
following checks and adjustments must be made periodically.
Checking and adjusting the circular level
Using the leveling screws, place the bubble in the center of the circular level and
rotate the telescope 180°. The bubble should remain in the center (Fig. 9). Otherwise, it is
necessary to carry out an adjustment.
Fig. 9 Fig. 10
Adjustment is performed as follows: turn the leveling screws until the bubble is half
close to the center of the circular level (Fig. 10).
Then, using a hex wrench, bring the bubble to the center of the circular level by turn-
ing the two adjusting screws (Fig. 11).
Fig. 11
