Abrams SC-1, Техническое руководство

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INSPECTION
AND
MAINTENANCE
(5) Using the Sun Compass
before
6
A.M.
and after
6
P.M.
The sun compass can
be used
during
the hours
of
sun
light
before
6
A.M.
and
after
6
P.M.
;
however,
it
is necessary
to
make
a
mental change
beyond the
6
o'clock positions
in
the
numbers representing the hours
on
the solar plate.
That
is,
the numbers should progress
from
6
P.M.
to
7, 8,
etc.
and from
6
A.M.
to S, 4, 3, etc.
The
numbers are reversed at the
6
o'clock
position
so
that
the
solar plate
will
apply
to
both north and
south latitudes.
SECTION
V
INSPECTION
AND
MAINTENANCE
1.
INSPECTION.
a.
The
instrument should
be
periodically
inspected
to de
termine the condition
of
the parts and
to
determine
if
any parts
are missing.
6.
Check the moving
parts of
the
gimbal mounting for
free
movement
and
see
that they
can be
securely clamped
in
a
rigid
position
by
turning
up
on the
wing
nuts.
o.
Check
the
level
vial
and
the etched
surfaces
of
the pro
tractor, date bar, and solar plate
for legibility.
d.
Check the gnomon rod, sighting rods, and shadow bar
for
straightness, and
see
that the luminous
tips of
the gnomon
and sighting rods are not broken.
2.
MAINTENANCE,
a.
Very little
maintenance
is
required
for this
instrument.
b.
The parts
are
light
and consequently should
be handled
with
care.
The
gnomon and sighting rods should
be
carefully
installed
to
prevent bending
them.
c.
The instrument should
be
kept clean at
all
times, for
upon
this
depends
its legibility
and consequent usefulness.
It
should
be
properly packed away in the
carrying
case
when not in
use.
SECTION
VI
DISASSEMBLY, INSPECTION,
REPAIR, REASSEMBLY
1.
DISASSEMBLY.
{See
Figure
9.)
a.
Remove
the
Gnomon and sighting rod
from
the compass.
6.
Unscrew
the
clamping nut (item 2) from
the
pivot bolt
21