TM 5-6675-312-14
(2) If necessary, install the battery box assembly (fig. 3-1).
(3) If necessary, install the handlamp (fig. 3-2) or the plug-in lamp (fig. 3-3).
(4) If necessary, install black eyepiece filter (fig. 2-23).
(5) Center and level theodolite (para. 2-8a).
(6) Install circular compass assembly (fig. 3-5).
(7) Aline theodolite with known magnetic bearing using horizontal drive screw (19, fig. 2-1).
(8) Loosen clamp assembly (3, fig.2-2).
(9) While looking into eyepiece assembly (5, fig. 2-2), rotate eyepiece assembly to focus circular compass
assembly heading indication.
(10) Rotate spring loaded knob (2, fig. 2-2) counterclockwise and hold.
(11) Rotate compass housing (4, fig. 2-2), while viewing compass heading through eyepiece assembly (5, fig.
(12) Release spring loaded knob (2, fig. 2-2).
NOTE
In order that the circular compass assembly pivot friction will always act in the same direction
the last half turn of the horizontal drive screw (19, fig. 2-1) should always be made in the
clockwise direction.
(13) All subsequent reading will be magnetic bearings.
(14) The metal circle (6, fig. 2-2) around the base of the circular compass assembly carries a short scale. This
metal circle can be moved independently of both the compass base and housing, provided that the three
screws underneath the compass base are loosened. With the three screws loosened, rotate the metal
circle so that the zero of the scale or the amount of local declination is alined with the index mark
underneath the
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