TM 5-6675-250-20
2-16. DETERMINATION OF AZIMUTH VALUE FOR REFERENCE MIRROR (Continued)
L O C A T I O N / l T EM
A C T I O N
R E M A R KS
SERVICE (Continued)
al.
Adjust the micrometer control (38) to position
the fixed index mark of the horizontal scale to
the center of the nearest double line.
a m.
If the vernier scale does not appear under the
fixed index, adjust the micrometer control to
position the fixed index mark of the horizontal
scale to the center of the second nearest dou-
ble line.
a n.
Record the horizontal scale reading as
f o l l o w s:
(1) if the fixed index is
over a three-digit
number, record the
number as it ap-
pears and add a
zero as the fourth
d i g i t.
(2) If the fixed index is
over a number 5,
record the
preceding three-
digit number and
add a 5 as the
fourth digit.
2-86
