Horizontal axis
- seotskpak
- Dec 7, 2016
- 2 min read
It is the axis of rotation of the telescope in the vertical plane. It is also known as the turning axis. Temporary adjustment; the setting of the theodolite over a station at the time of taking any observation is called temporary adjustment. This adjustment is necessary for every set up of the instrument. Permanent adjustment; when the desired relationship between the fundamental lines of theodolite is disturbed, then some procedure are adopted to establish this relationship. This adjustment is known as permanent adjustment. Technical Data used in the field explained in civil surveyor course in rawalpindi. Last count of the vernier; this is the difference between the value of the smallest division of the main scale and that of the smallest division of the verneir scale. It is the smallest value that can be measured by a theodolite.
The diaphragm; the diaphragm is a brass ring consisting of cross-hairs, or one containing a glass disc with fine lines engraved on it . It is placed in position by turning four capstan-headed screws and can be moved up, down or sideways when required. It is fixed in front of the eye-piece. The cross hairs may be made of spider we or fine platinum wire; they may also be in the form of a fine scratch mark engraved on glass. Some more details of civil surveyor course in rawalpindi are as under. The vertical hair or hairs are meant for checking the vertically of the staff or target. The middle horizontal hair corresponds to the collimation line. The upper and lower short horizontal lines are called the upper and lower stadia.
Sensitiveness of bubble tube; the ability of bubble tube to show a very small deviation of the bubble from its horizontal position is termed as the sensitiveness of the bubble tube. It depends on the following factors; (a) the radius of curvature of the bubble tube. (b) The diameter of the bubble tube. (c) The length of the bubble tube. (d) The viscosity of the liquid used inside the tube. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join civil surveyor course in islamabad.
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