M-6 later-model forward view
RESTRICTED
M-6 Later
Models 20
Degrees
Fig. 38
permits the quadrant to be rotated 7 degrees.
While the seven
extra
degrees
are
set in,
the
quadrant cannot be rotated because the stud
hits
the projection and the camway is above the stud.
The auxiliary search knob must
be held in position
sighting angle is utilized because
the quadrant return spring will force the quadrant
back to maximum position, or 70°
sighting angle.
It must be remembered that in the M-6 series
with 7 degrees
extra sighting angle
the entire
quadrant is rotated 7 degrees and that the extra
degrees can be set
in only when the telescope quad-
is at 70 degrees sighting angle and
auxiliary search
knob must be
rotated and held in
place if the 7°
is obtained.
later models of the M-6 series has a 20
degree forward view mechanism.
This mechanism
consists of an auxiliary search knob, spring anc
intermediate
gears.
The
construction of this mechanism permits
setting in of the
additional 200 independently of
the position of
telescope quadrant.
The 20°
extra sighting
angle is set.
follows. Push in on the auxiliary
search knob
and
turn clockwise.
When the auxiliary knob is
pushed in the forward view engaging gear is pushed
in and the projectic on that gear is disengaged
from
the notch
in the cable operating shaft col-
lar. Rotate the auxiliary search knob clockwise.
The
eccentric clamp is notched
for the project-
ions on
the engaging gear and the two are always
engaged.
The
eccentric clamp is slotted and
in
the operating shaft.
This pin acts as a stop if
the collar becomes worn and no longer stops the
forward movement of the auxiliary search knob.
The notches in the cable operating shaft col-
lar are spaced
so that as the engaging gear and
cable operating sheave are rotated the mirror is
turned through an angle of 20 degrees.
A spring
inside the
engaging gear keeps it engaged once the
arciection
sir themetches of the operating shaft
sor as on
the aux! lary search knob
shaft
is for positive disencagement of the auxiliary
search
knob sraft cinion
and the engaging gear on
the cable operating
shaft.
The additional
20 degrees sighting angle
gives
a
total sighting angle of 90 degrees.
87