FOR
M2
OR
M2A2
AIMING
CIRCLE
DECLINATION PROCEDURES
3 Point elbow telescope in the general direction of NORTH.
NOTE
The aiming circle magnetic compass cannot be used near iron
or steel masses as inaccurate readings will result.
4 Unlock magnetic compass needle.
5 Turn orienting knobs until magnetic compass needle is centered on the middle reticle.
Look through magnifier.
6 Turn azimuth knob until elbow telescope reticle alines with a point of known azimuth.
Record this indication. Do this process four times and record the average of these four
indications. Subtract this average from the known Grid-Azimuth (add 6400 roils to the
Grid-Azimuth, if necessary). This is the declination constant of the instrument.
7 If more than one point of known Grid-Azimuth is visible, repeat the computation for each
point and take the average of these computations as the declination constant.
8 Lock magnetic compass needle.
