TM 11-2323
C4
Page 7, paragraph 5. Make the following changes :
Subparagraph b(1).
Delete the heading and Substitue:
Head-support post, Projectors PH-637/PFP and PH-637A/
PFP, and Projector, Still Picture PH-637B/PFP.
Add subparagraph (1.1) after subparagraph (1):
(1.1) Head-support post, Projector, Still Picture PH-637C/PFP
(fig. 2.2). The support post has a rack secured to the upper
end by two screws. The lower end of the support post fits
through two adjustable locating brackets in the yoke. T h e
projecting studs of a locating pin in the support post fit
in two notches cut into the flanges of the upper locating
bracket on the top of the yoke. The support post is locked
into position by a clamping knob located on the rear plate
of the yoke.
Subparagraph b( 2 ) . Delete the heading and substitute:
Projection head assembly,. Projectors PH-637/PFP and PH-
637A/PFP, and Projertor, Still Picture PH-637B/PFP.
Page 8, paragraph 5b (2). A d d S u b p a r a g r a p h ( 3 ) a f t e r s u b p a r a -
graph (2):
(3) Projection head assembly Projector, Still Picture PH-
637C/PFP (fig. 2.2). The projection head assembly consists
of a mirror housing, a projection lens, and a support arm.
The mirror housing contains the front surface mirror and
a window. An elevation knob at the back of the mirror
housing is used to adjust the vertical angle of the front sur-
face mirror. The support arm houses a pinion gear (which
engages the rack on the support post), that is controlled by
the focusing knob; it also houses a 14-inch focal length pro-
jection lens, which is secured in position by a retaining ring
that engages the upper portion of the lens barrel. A lens cap
is provided to protect the exposed lens element.
Subparagraph d, next to the last line. After "PH-637A/PFP",
add : and the PH-637C/PFP.
Subparagraph e (1). Delete the heading and substitute:
Aperture plate holder, Projectors PH-637/PFP and PH-
637A/PFP, and Projector, Still Picture PH-637B/PFP.
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