16-mm film. The 16-mm films are used exten-
sively for training, briefings, and entertaining
The 16-mm motion picture projectors can be
operated virtually anywhere that 105-125V
(50-60Hz) alternating current is available. Most
of these projectors will project silent or sound
motion pictures. There are some projectors
however, that project either silent or sound but
Most projectors are equipped with built-in
sound systems capable of working with or
without separate amplification equipment.
Usually, a speaker is supplied with the projector.
In many models the amplifier-loudspeaker com-
ponents are mounted in the projector case.
Principles of Operation
The operation of the various makes and
models of motion picture projectors is very
similar. Read the instruction manual for each
different projector before operating that par-
SETTING UP THE PROJECTOR.When
using a portable screen, set it up relative to the
audience size. Position the projector stand or
sturdy table at the approximate correct distance
from the screen. Place the projector on the
stand. It must be high enough so that the pro-
jected light will be above the heads of the
audience to prevent shadows on the screen. Con-
nect the power cord to a three-prong outlet. If
the presentation is with sound, turn on the
volume control to warm up the amplifier tubes.
(NOTE: All transistor amplifiers require very
Most reel arms are permanently mounted to
the projector requiring only that you raise and
lock them into place. In older models however,
the reel arms must be assembled; if so, remove
them from the carrying case and secure them to
Place the reel holding the film on the front
arm and an empty reel on the rear arm.
Figure 7-15 is a side view of a manual
threading projector and is typical of many pro-
jectors in use. Study this figure to become
familiar with the important parts of the projec-
MANUAL THREADING.Most projec-
tors have a threading diagram displayed
somewhere on the projector body. Find detailed
threading instructions in the manufacturers
instruction manual for the particular make and
model projector you are using. Be sure that the
sprocket holes are engaged with the sprocket
teeth. It is also important that you form proper
sized loops above and below the film gate. The
upper loop permits intermittent movement of
the film. The lower loop prevents this irregular
motion of the upper loop from affecting the
smooth feeding of film through the sound head.
threading greatly simplifies your task of prepar-
ing for a presentation. The following steps are
used to thread a projector with the automatic
threading feature: First, ensure that the end of
the film leader is squarely cut. Move the
threading control lever to the load position.
Insert the end of the leader into the input chan-
nel, engaging it with the upper sprocket. Switch
the projector to run. The projector will thread
automatically. When the leader exists at the rear
of the projector, turn the projector off. Tug
gently on the end of the leader. This action
releases the automatic threading mechanism.
Wrap the film to the takeup reel. This completes
the threading operation.
STILL PICTURES.Some projectors are
designed to stop on individual frames, per-
mitting them to be shown as still pictures. To
show a single frame, rotate the still picture con-
trol to STILL or depress the STILL button,
whichever is appropriate for the specific projec-
tor. Frequently you must refocus to bring out a
sharp still picture.
A heat shield will
automatically drop into position protecting the
film from heat damage. This shield blocks off
much of the light and dims the picture. (Full in-
tensity of light from the projector lamp would
heat the film to its melting point in just a few
seconds.) Turning the control switch to STILL
or depressing the STILL button removes power
from the the drive motor, stopping the main
drive shaft. The heat shield is then pulled into
the optical path by the return spring.