Right-hand side of pro-
Locks poet in position.
Head-support post lock-
jector housing near
Racks projection head up
Focusing knob (fig. 2) - - - On split tube at end of
or down for focusing
projection head sup-
Varies vertical angle of
Mirror elevation knob On back of projection
front surface mirror;
moves i m a g e u p o r
down on screen.
ON-OFF switch (fig. 2) - - On front of housing - - - - -
Turns projector power ON
or OFF; controls lamp
On rear of housing (PH-
Winds up used cellophane
Take-up roll attachment
637A/PFP) ; left side of
on take-up spool.
On front of housing (PH-
Rewinds cellophane ma-
Supply roll attachment
637A/PFP); right side
terial back on supply
of housing (PH-637/
13. Placement of Projector
a. Set the projector, on its support, in front of the audience so that
the window in the projection head faces the screen. Exact placement
of the projector and the screen depends on the following :
(1) Size of screen image desired (par. 11 a).
(2) Height of screen.
(3) Height of projector from floor.
(4) Rest viewing angle for audience.
b. If the lecturer is to sit at the projector, adjust the height of the
screen so that it will be viewed over the projector head. If the lecturer
will stand, adjust the position of the screen so that viewing will not
be obstructed by either the lecturer or the projector. If a large image
is required in a low-ceiling room, adjust the relative positions of the
projector and screen for an oblique viewing angle to insure maximum
After the best possible placement of the projector and screen has
been determined, proceed as follows-
a. Remove the lens cap, and throw the ON-OFF switch to the ON