111. Selecting audio-
visual equipment
Development and Exchange of Instructional
Resources in Water Quality Control Programs
Charles County Community College
La Plata, Maryland
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Development and Exchange of Instructional
Resources in Water Quality Control Programs
111. Selecting audio-
visual equipment
Environmental Protection Agency
Charles County Community College
1974
-------
The mention of trade names or commercial products in this manual is for illustration purposes,
and does not constitute endorsement or recommendation for use by the Environmental Protection
Agency.
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Project funded by
Manpower Development Staff
Office of Water Program Operations
Environmental Protection Agency
Grant Number 900253
Awarded to
Charles County Community College
La Plata, Maryland
Carl M. Schwing, Project Director
Report prepared by
Donald K. Moon
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Preface
To meet proposed federal and state water quality standards, both for drinking water and waste-
water treatment plant effluents, the treatment plants of this country must have qualified
personnel continually upgraded with the latest technology. The broad spectrum of competencies
required of such personnel, coupled with the wide geographic distribution of trainees (existing
operating personnel, as well as new entries), suggests the need for high quality instructional
systems. To be effective, these systems need improved instructional materials and qualified
instructors. This series of reports (Volumes I-IV) reviews the present status of available
instructional materials and equipment and offers suggestions about how to select equipment.
Guidelines are given for the production of instructional materials which should lead to maximum
flexibility and economy.
The initial four volumes in this report are:
Volume Title
I Audio-Visual Equipment on Hand
II Instructional Materials Available
III Selecting Audio-Visual Equipment
IV Selecting Instructional Media and Instructional Systems
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Acknowledgements
This report series is a cooperative effort between persons with technical competence in the water
quality control field and instructional technologists with competence in instructional system
development. The overall administration of the project has been under the direction of Carl M.
Schwing. The preparation of Volume III: Seleating Audio-Visual Equipment was directed by
Donald K. Moon. The following have served on the advisory committee for the project:
Representing the Environmental Protection Agency:
Joseph Bahnick, Acting Chief, Direct Technical Training, Manpower Development Staff,
OWPO/EPA
Kenneth M. Hay, Education Specialist, Direct Technical Training, Manpower Development
Staff, OWPO/EPA
Harold L. Jeter, Director, National Training Center, Manpower Development Staff, EPA
George H. Ziener, formerly Chief, Instructional Development Section, Air Pollution
Training Institute, EPA
Representing Charles County Community College:
Walter J. Bojsza, Audio-Visual Coordinator, Learning Resource Center
Carl M. Schwing, Chairman, Pollution Abatement Technology Department
Consultants:
John H. Austin, Professor and Head, Environmental Systems Engineering, Clemson University,
Clemson, South Carolina
Ross J. Comwell, Assistant Director of Public Relations, Clemson University, Clemson
South Carolina
W. Harry Durham, Director, University Comnunications Center, Clemson University,
Clemson, South Carolina
Robert A. Gearheart, Division of Environmental Engineering, Utah State University,
Logan, Utah
Donald K. Moon, Director, Educational Media Services, Drake University, Des Moines,
Iowa
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Table of Contents
Page
Summary 1
Recommendations 2
Introduction 3
Glossary 4
General Criteria for Audio-Visual Equipment Selection
(Usefulness, Operability, Performance, Safety, Comparability, Sturdiness, Repairability,
Reputation of Manufacturer, Reputation of Dealer, Warranty, Cost) 7
Snecific Equipment Criteria 9
16mm Motion Picture Projectors 10
8mm Silent and Sound Projectors 12
2"x2" Slide Projectors (Automatic, Semi-automatic, and Manual) 14
Sound Filmstrip Projectors and Viewers 16
Overhead Projectors " 18
Tape Recorders (Reel-to-Reel and Cassette) . 20
Video Tape Recorders 22
References 25
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SELECTING AUDIO-VISUAL EQUIPMENT - 1
Summary
The selection of audio-visual equipment must be
preceded by the establishment of performance
objectives for trainees and the correlation of
the attainment of these objectives with appro-
priate media (instructional materials and audio-
visual equipment). Each piece of audio-visual
equipment should be evaluated thoroughly prior
to purchase by investigating each of the follow-
ing: usefulness, operability, performance,
safety, compatibility, sturdiness, repairability,
portability, reputation of manufacturer, reputa-
tion of dealer, warranty, and cost. The following
types of equipment are discussed, and worksheets
given for use in evaluating each piece of equip-
ment: 16mm motion picture projectors, 8mm silent
and sound projectors, 2"x2" slide projectors
(automatic, semiautomatic, and manual), sound
filmstrip projectors and viewers, overhead pro-
jectors, tape recorders (reel-to-reel and
cassette), and video tape recorders.
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2- VOLUME 111
Recommendations
1. Methods of evaluating audio-visual equipment
and selecting the appropriate equipment for
each training situation should be continually
updated and made available to training organi-
zations in the water quality control field.
2. Professionals in the water quality control
training field should establish standards for
audio-visual equipment in order to promote
compatibility of the instructional materials
being produced for this equipment.
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SELECTING AUDIO-VISUAL EQUIPMENT - 3
Introduction
Selecting audio-visual equipment can be a difficult
and time consuming task because of the multitude of
models and formats and wide ranges of costs from
which one may choose. However, there are some
guidelines which can assist in selecting audio-
visual equipment to meet particular needs. This
report will present and analyze these guidelines
as they relate to general criteria applicable for
selecting all equipment, and special criteria
applicable to particular types of equipment. No
attempt is made to compare one brand or model with
another. Brand comparison has much merit and
should be made before any equipment is purchased,
but it can be made fairly only after one has
determined which features are desirable in the
equipment needed and which models can be compared
adequately. An evaluation form is included which
provides criteria for making performance compari-
sons.
The initial step in audio-visual equipment selec-
tion is a careful determination of the task, goal,
or objective to be accomplished. There is some
evidence that certain equipment may have higher
correlation than other equipment with the accom-
plishment of certain types of learning objectives.
It is suggested that the communication ^unctions
of (1) gaining and controlling attention, (2) pro-
viding a model for expected learning outcomes,
(3) stimulating recall of prerequisite capabilities,
(4) presenting stimuli for learning, (5) providing
guidance for learning, and (6) appraising learner
performance, may be performed by any medium during
the course of instruction. Many combinations of
objects, devices, and verbal coinmmications may be
employed to establish suitable conditions for
learning. There are usually several available
alternatives for accomplishing the same function.
For any given function, certain means of inter-
acting with the learner may be more effective
than others, thus the characteristics of the
various media for instruction in performing these
functions need to be considered carefully in
making the best choice from the alternatives
available.
In most cases a given learning task may best be
approached in a multi-media learning environment.
In this kind of environment, sound (narration) is
used to accompany motion pictures or still pic-
tures (oral or recorded, e.g., sound slide series
or sound filmstrips), and demonstrations are
accompanied by oral presentations and the use of
objects, still pictures, and motion pictures.
This multi-sensory learning environment capitalizes
on the strength of each particular medium and at
the same time attempts to reach each student in a
way which most nearly corresponds with his learning
style, reading skill, and possession of prerequisite
knowledge.
The proceudres to use in establishing learning ob-
jectives and correlating these with instructional
materials and audio-visual equipment are covered
in Volume IV: Selecting Instructional Media and
Instructional Systems of this report series. This
volume will concern itself only with the selection
of the equipment.
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4-VOLUME III
Glossary
(Definition of terms used in this report)
Term
Affective
Audio Tape
Audio Tape Recorder
Audio-Visual Equipment
Cognitive
Curriculum
Diazo Process
Filmstrip
Instructional Materials
Instructional Medium
Instructional Package
Definition
A type of learning that pertains primarily to values.
A polyester or mylar base tape with a magnetic oxide
coating capable of recording and reproducing sound
when used with an audio recorder/player. Audio tape
is available in a number of different sizes (widths)
and formats: 1/4-inch reel, 1/8-inch cassette, or
1/4-inch cartridge.
A piece of equipment capable of recording and repro-
ducing sound using a magnetic oxide tape.
Equipment which presents materials either aurally,
visually, or both. Audio-visual equipment is often
referred to as hardware.
A type of learning that pertains primarily to facts.
A course of study involving a number of different
subjects.
A method of producing images on a treated paper or
an acetate base. Ultraviolet light exposes a drawing
or lettering on the treated film or paper. Anmonia
vapor develops the unexposed portions of the image.
The color of the image is determined by the special
coatings on the paper or film. This process is used
to produce blueprints and overhead transparencies.
Images on a clear acetate base which are viewed by
having light projected through them. Several images
are on one piece of film. Usually the film is 35rm
in width and the images, either black-and-white or
color, are normally arranged vertically on the film.
Printed matter, slides, tapes, models, films, or
actual objects which are used as a direct paTt of
the teaching/learning process. Instructional mate-
rials are often referred to as software.
The combination of instructional materials and
audio-visual equipment. A 35mm slide used in a
slide projector establishes the medium of the 35nm
slide.
Materials necessary to accomplish a selected portion
of training. The package may include lecture notes,
outline, printed text, 35mn slides, audio tapes,
video tapes, films, etc., or any combination of the
above.
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SELECTING AUDIO-VISUAL EQUIPMENT - 5
Term
Instructional Resources
Lecture
Microforme Materials
Microforme Reader
Motion Pictures
Motion Picture Projector
Overhead Transparencies
Printed Materials
Psychomotor
Simulation (noun)
Simulation (verb)
Slides
Definition
The complete spectrum of facilities, equipment,
materials, and personnel involved in preparing,
presenting, and evaluating instruction.
A class taught by an individual relying primarily
on the spoken word reinforced by body movement and
gestures and simple chalkboard illustrations.
Photographic miniatures of printed text, line
drawings, and full tonal photographs. Microforme
may be in filmstrip sizes, 35mm 16mm, and 8mm; or
microfiche (4x6-inch sheet of film containing many
images).
A piece of equipment capable of displaying in
legible size, printing, drawings, and photographs
reduced to a microforme format. Microtome formats
include 35mm, 16mm, and microfiche (4"x6"). Some
microforme readers are capable of handling more than
one format.
A series of still images photographically applied to
a strip of film capable of producing the illusion of
full motion when used in a motion picture projector.
Motion pictures may or may not have sound or color.
A number of different film sizes are used in instruc-
tion. The primary sizes are 16mm (width), 8mm
(width), and Super 8nm (width and increased image
size). Motion pictures are often packaged in a
variety of ways: for reel-to-reel use, Super 8nm
cartridge use, etc.
A piece of equipment capable of projecting a moving
image from a piece of motion picture film. Some
projectors are capable of reproducing sound in addi-
tion to projecting visual images. Different models
of motion picture projectors are designed to handle
various film sizes, for example, 8mm, Super 8mm,
16nm, and 35mm. Normally, a motion picture projector
can handle only one film size.
8"xl0" or 10"xl0" sheets of film capable of carrying
an image (full tonal photographs, line drawings, or
lettering). Overhead transparencies are used with
overhead projectors and may be in full color, single
color, or black-and-white. (Two popular ways to
produce overhead transparencies are through use of
the diazo or the thermal processes.)
Words and pictures printed on good but not highest
quality paper stock (i.e., a workbook) designed for
one receiver at a time. (Usually printed materials
do not involve color pictures unless high volumes
are justified.)
A type of learning that pertains primarily to physical
skills.
Any device or model which can provide a three-
dimensional representation of the actual equipment
or device which would be found "on the job."
The act or process or pretending certain conditions
exist. Various disorders are simulated in training
situations in order to teach the proper response to
trainees.
Small pieces of film capable of storing photographic
images which are viewed by light transmitted through
the film base. The photographic images may be 35jim,
126mm, or other sizes of film, which are usually
mounted in plastic or cardboard frames with an over-
all dimension of 2"x2". (Even filmstrips classify
as slides using this basic definition. However,
instead of mounting the images individually in small
frames, the images are mounted on a flexible piece
of short film.)
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6-VOLUME III
Term
Definition
Slide/Tape
Still Transparency Projector
Synchronizing Equipment
Television
Thermal Process
Video Tape
Video Tape Playback Unit
Video Tape Recorder
Photographic images viewed by light transmitted
through a film base and an audio tape related to
the images. The images may be on 35mm slides, 126mm
slides, or other sizes, or even in filmstrip form.
The slides are usually in color but do not have to
be. The audio tape may be in reel or cassette format
and may be synchronized with the slides through the
use of an inaudible tone which changes the slides
automatically or through an audible tone which indi-
cates to the operator that a change should be made.
Equipment capable of projecting an image from a piece
of photographic, diazo, or thermal film. Different
models of still transparency projectors would be
capable of handling different size transparencies,
such as 10"xl0" slides, 35mm slides, 35mm filmstrips,
and 16mm filmstrips. Usually a projector is capable
of handling only one size of film.
Equipment used to coordinate slide and sound presen-
tations. Usually a stereo audio tape recorder contains
the aural presentation on one channel and the slide
changeT signals on the other channel. A connecting
device advances the slides according to the signals
on the audio channel.
Images displayed on a television receiver. Sources
for the images may be "live" (i.e., using TV cameras
to transmit images of performers in a studio or a
remote setting), video tape, or film.
A method of producing images on treated paper or an
acetate base. The exposure of the drawing or lettering
on the base material is made by a heating element',
usually a bright light-tube. Since there is no "de-
veloping" of the image in the thermal process, the
process is faster than the diazo method of producing
transparencies. However, thermal transparencies,do
not have the detail or the brilliant color of diazo
transparencies.
A polyester or mylar base tape with a magnetic oxide
coating capable of reproducing television images and
sounds when used with a video tape recorder/player.
Equipment capable of displaying television pictures
and sounds recorded on magnetic tape.
Equipment capable of recording television pictures
and sound onto magnetic tape. Normally, video tape
recorders are also capable of playing {jack recorded
materials.
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SELECTING AUDIO-VISUAL EQUIPMENT - 7
General Criteria for
Audio-Visual Equipment Selection
Following are some basic criteria which may be
applied to the evaluation of almost all types of
audio-visual equipment. Other more specific
criteria related to individual items will be found
in the next section. The order of presentation
does not indicate relative importance. .
USEFULNESS
Usefulness should be evaluated on the basis of
instructional materials available for the equip-
ment (either commercially available or those which
you may produce yourself) which will contribute
to the accomplishment of your objective. Equip-
ment has its greatest usefulness when adequate
instructional materials are available for it.
OPERABILITY
Is the item simple and relatively foolproof to
operate? Does it have to be operated by a specially
trained technician, or can its operation be learned
easily by inexpert users? Before selecting equip-
ment, determine who the persons are who will be
operating the equipment, their degree of expertise
in working with the equipment, the amount of
training which might be necessary to instruct
them in the operation of the equipment, and how
this instruction will be provided. Instructions
which accompany the equipment should be clear
enough so that a novice will be able to operate it
with a minimum of confusion unless specific
training is to be provided. Frustration with the
operation of any piece of equipment creates both
physical and psychological problems for the user
and could markedly decrease the value of instruc-
tion.
PERFORMANCE
Will the item perform in accordance with the
specifications set forth by the manufacturer and
in accordance with accepted standards of effi-
ciency for its various optical, electronic, and
mechanical systems? Does the item operate at
satisfactorily low noise levels? Will it continue
to operate over long periods without excessive
heating or wear? In other words, how reliable is
it?
SAFETY
Does the item provide adequate safety features?
Are turning gears protected? Is the chassis
grounded? Do lenses have limit stops to prevent
their being dropped accidentally when fully ex-
tended? Is the unit equipped with a three-wire
grounding plug? Does the equipment have a
sufficiently long power cord to make the use of
extension cords unnecessary in most situations?
Is the power cord permanently connected to avoid
the possibility of its being lost? Are plugs so
designed to minimize the possibility of their being
inserted in the wrong position or manner, possibly
with disastrous results? Is the item properly
balanced to reduce hazards of toppling? Does the
equipment have detachable pieces which are likely
to become lost? Do sharp edges or points provide
safety hazards? Can the item suitably be enclosed
in a case or otherwise protected when being trans-
ported?
COMPATIBILITY
Is the equipment compatible with other equipment
previously purchased so that materials in the
present collection can be used interchangeably, or
does it require the purchase of special materials
specifically produced for it? This is an extremely
important factor, for compatibility is directly
related to flexibility in using the equipment.
There are some expensive changes being made in the
format of 8mm projectors and in the frequency and
format of tape recorders using inaudible signals
for automatic advance of slide and filmstrip pro-
jectors and viewers. This will be covered in
greater detail in the following section of this
report.
STURDINESS
Is the item built of sufficiently strong materials
to withstand the use planned for it? Are fittings
(handles, knobs, dials, switches) of top quality?
If the items are to be carried often, is the carry-
ing handle sufficiently strong to provide for con-
tinued transportation in this manner? If plastics
are employed in construction, will they withstand
the kinds of usage to be expected for the item?
Will the item be exposed to heat or sunshine over
long periods and, if so, what effect will this have
on deterioration of the case or parts of the item?
REPAIRABILITY
Can the item be repaired locally or must it be
shipped back to the factory? Are repair parts
normally available locally or must they be
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8-VOLUME III
ordered from the factory? The last questions can
be particularly important with items not manu-
factured in this country. Is the item designed
so that it can be repaired with few specialized
tools?
PORTABILITY
If the item is to be lifted or carried, is it
sufficiently lightweight to be handled easily
by the user? Is it so large that it is un-
necessarily awkward to carry? For heavier items,
are the handles positioned satisfactorily for
proper balance and ease of carrying? Are two
handles provided if transporting the item may
require more than one person?
REPUTATION OF MANUFACTURER
Does the manufacturer have a reputation of pro-
ducing a quality item? Does the item itself have
an established reputation for quality and utility?
There are many new companies in the business of
manufacturing media equipment. Although most of
them no doubt try to produce a quality product,
many of them have not had to stand the test of
time.
REPUTATION OF DEALER
Is the dealer's reputation well established as
being fair and honest with regard to price,
delivery, service to the item, warranty, or
similar matters? Will the dealer provide in-
service training in operation or maintenance of
the item? "A pieae of equipment is no better
than the dealer who seVLe it" is a maxim worth
remembering.
WARRANTY
What is the warranty with respect to the number of
months of free service, including replacement of
defective parts or when justified, of entire items?
Are restrictions placed on the warranty in terms of
(a) voiding the warranty for such things as local
attempts to repair the item, (b) the necessity to
return the item to the dealer where it was purchased,
or (c) the need to return it to the factory?
COST
Is the price of the item in line with those of
competitive makes of the same type and quality?
If higher, is the amount justified by superior
design, performance, construction, or other
features? If trade-ins are involved, are they
related realistically to the price of the new
items?
The last item in this section on general criteria
for selection of audio-visual equipment is cost.
Most often cost is put at the top of the list when
determining equipment selection with a tendency to
buy that equipment which can be purchased at the
least cost. Cost, however, is a relative factor
and should be considered only in relationship to
the above criteria and the special equipment
criteria found in the following section. The
familiar adage "you get what you pay for" is more
often true than not when purchasing audio-visual
equipment. The difference in cost for a high
quality item will, in most cases, be justified by
the results of its use. Where criteria have been
carefully determined and specified, competitive
bidding provides the best product at the lowest
possible price.
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SELECTING AUDIO-VISUAL EQUIPMENT - 9
Specific
Equipment Criteria
This section will consider criteria for decision-
making which can be applied to specific kinds of
audio-visual equipment. It will include criteria
for the selection of 16mm sound motion picture
projectors, 8mm silent and sound motion picture
projectors, 2"x2" slide projectors, 35mm filmstrip
projectors, sound filmstrip projectors and viewers,
overhead projectors, reel-to-reel and cassette
audio recorders, and video tape recorders.
For each type of equipment specified above, a
general introduction indicating some of the trends
in new formats or features is provided. In addi-
tion, a check sheet is provided for each type of
equipment with special criteria which should be
considered in selecting that particular piece of
equipment. The criteria should be examined in
terms of your particular needs and checked accord-
ingly in the columns marked "Sot Required, "
"Desirable," or "Required." After determining the
relative importance of the criteria in your particu-
lar situation, it is suggested that you rate the
particular piece of equipment with regard to whether
it is "Unacceptable," "Acceptable," or "Excellent"
in meeting the criteria you have determined to be
important. This should give you a basis for com-
paring one model of equipment with another. (A
note of caution: When making these comparisons,
be sure in your test you compare models with like
features, and that these tests, where possible,
are made under the same conditions.
Most of the criteria suggested are not presented
in terms of technical standards, except those which
most generally can be determined by the specifica-
tions stated by the manufacturers. Although manu-
facturer specifications may not present an absolutely
true picture, they should provide some guidance in
evaluating equipment where trained electronic tech-
nicians are not available to make these evaluations.
Using the following criteria, anyone should be able
to make a decision about the merits of any brand or
model of equipment after thoroughly studying the
equipment, the operator's manual for the equipment,
and the manufacturer's specifications.
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10-VOLUME III
16MM MOTION PICTURE PROJECTORS
Insta-Load, Auto-Load, and Self-Threading are terms
used to describe the relative ease of operating
different 16mm projectors available today. Projec-
tors with these features each have their relative
merits. You must decide which one best suits your
needs.
The advantages of 16mm projection equipment are
that: (1) it can be used with both large and small
groups (16mm projectors with high intensity arc
lamps are available for use in very large settings),
(2) the 16mm format is a worldwide accepted
standard, and (3) there are literally thousands of
films available for use on this projector. Its dis-
advantages are (1) weight may be a problem in terms
of portability, and (2) the relative high cost of
the equipment compared with 8mm projectors.
Features now available in 16mm projectors include:
(1) single-frame advance and reverse, (2) fast
forward and reverse while the film is still in the
threading path of the projector, (3) a footage)
counter for determining the location of particular
segments of a film, (4) still picture projection,
and (5) in-path rewinding of film. Each of these
features provides additional flexibility in uti-
lizing this type of equipment. Unfortunately,
they all are not available on any one projector,
so it is necessary to decide which of the features
are most important in meeting the needs of your
particular situation.
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16mm Motion Picture Projectors
Manufacturer
Model
Physical
1. Operates smoothly and quietly.
2. Threading process simple enough to prevent misthreading.
3. Automatic threading machine can be threaded manually.
4. Automatic threading machine can be unthreaded easily before film
is completely through.
5. Lower loop restorer
a. automatic
b. manual
6. Accepts 2000 ft. reel of film (50 minutes).
7. Permanently attached grounded power cord.
8. Can be reversed without loss of loops.
9. Portability
a. weight
b. location of handle(s)
10. Switches for operational functions located in easily reached locations.
11. Switches and controls clearly marked.
12. Ability to accept green (new) film.
13. Ability to accept spliced film.
14. Blower system keeps parts to be touched in operation cool under
sustained operation.
15. Can be easily serviced.
16. Special features
a. silent speed (not recommended unless needed)
b. fast forward and reverse
c. microphone input
d. still picture projection
e. single frame advance and reverse
f. footage counter
g. remote control capability
h. manual advance control for checking threading
i. threading lamp
j-
k.
Optical
1. Resolution of image.
2. Illumination of image (brightness) on screen for setting(s) in which
it is to be used
a. classroom
b. auditorium
3. Lenses of varying focal lengths available.
4. Image clear and steady.
Sound
1. Amplifier output satisfactory for setting (s) in which it is to be used
a. classroom
b. auditorium
2. Speaker
a. self contained
b. external speaker
c. speaker output jack
3. Noise level of projector does not interfere with the ability to clearly
hear sound by persons near the projector.
4. Fidelity of sound.
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12-VOLUME III
8MM SILENT AND SOUND PROJECTORS
The 8ram field is in a state of flux. Although
there is general agreement on the Super 8mm film
format for educational use, the equipment on which
it is used varies greatly. The projectors vary in
projection speeds, film format acceptable, use of
reel-to-reel films or cartridges of various con-
figurations (none of which are interchangeable),
and in the placement of sound track with respect
to the corresponding picture frame. However, some
standards have been proposed, and it is likely
that they will gain universal acceptance. These
are (1) Super 8mm as the standard format, (2) 18
F.P.S. (frames per second) as standard silent
speed, (3) 24 F.P.S. as sound speed, and (4) sound
recording will precede its corresponding picture
by 18 frames plus or minus one frame. It appears
that the Kodak cartridge is likely to become the
standard for cartridge-loaded projectors with
limited film footage capacity. Almost all 8mm
projectors are designed for use in relatively
small settings and should not be compared with
16mm projectors. Perhaps the best advice for
selecting an 8mm projector is select one which is
flexible in its use. The above-mentioned proposed
standards should be considered, as well as the
specific criteria below in selecting an 8mm projector.
The ease of operation of 8mm projectors, brought
about by self-threading and cartridge projectors,
has made this an appealing type of motion picture
equipment. The use of short, single concept
films--two to five minutes in length--which lend
themselves to independent study has been found to
be particularly valuable in instruction because
such films can isolate and emphasize one particu-
lar aspect or concept of a much broader topic.
The availability of easy-to-use cartridge-loaded
8mm cameras has made possible the local production
of these kinds of film to meet the needs of specific
. learning situations.
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Physical
1. Compatible with existing format of equipment owned.
2. Compatible with existing format of materials available.
3. Accepts Super 8mm film only.
4. Accepts Regular 8um film only.
5. Accepts both Super 8mm and Regular 8mm film.
6. Will accept
a. cartridge films
b. reel to reel films
c. both cartridge and reel to reel films
7. Cartridges can be loaded by user.
8. Maximum length of films which can be used.
9. Operates smoothly and quietly.
10. Continuous performance under sustained operation.
11. Threading system--simple and relatively foolproof.
12. Threading system
a. automatic
b. manual
13. Permanently attached grounded power cord.
14. Blower keeps parts touched in operation cool over periods of
sustained operation.
15. Special features available
a. can be synchronized with audio tape
b. remote operation
c. still picture
d. single frame advance and reverse
e. variable speed operation
f. automatic rewind
g. in path rewind
h.
i.
Optical
1. Lenses of varying focal lengths available.
2. Illumination of image (brightness) on screen for setting(s) in
which it is to be used.
a. classroom
b. individual viewing
Sound
1. Amplifier output satisfactory for setting(s) in which projector is to
be used
a. classroom
b. individual viewing
2. Headphone jack provided.
3. Sound--picture synchronization compatible with existing equipment owned.
4. Sound--picture synchronization compatible with available materials.
5. Provision for recording sound (magnetic sound projectors only).
6. Playback capability only.
7. Optical sound reproduction capability.
8. Magnetic sound reproduction capability.
9. Optical and magnetic sound reproduction capability.
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14-VOLUME III
2" x 2" SLIDE PROJECTORS
(AUTOMATIC, SEMIAUTOMATIC, AND MANUAL)
Although there are a number of good slide projectors
available, those projectors which use a round oar-
ousel tray or cartridge are becoming most widely
accepted. There have been attempts by various
manufacturers to develop projectors which will
accept the carousel slide tray, developed by East-
man Kodak, to provide for maximum interchange-
ability. These projectors utilize a gravity feed
method of placing the slides in the projector, a
method which has greatly reduced jamming of the
projector and damage to slides.
The ease of making high quality photographic
slides today with Inetamatio-type cameras, as well
as with easy-to-operate 35mm single lens reflex
cameras, has made this type of projector one of
the most popular in instruction. Eastman Kodak
markets a simple copystand utilizing an Inatamatic
camera, which permits relatively close-up copying
as well as the production of title slides and
slides of original graphic art.
The popularity of this type of equipment has been
increased by the development of cassette tape
recorders capable of synchronizing the slide pro-
jector with an audio tape (using an inaudible
signal recorded on the tape to automatically
advance the slides). Using this capability,
sunchronized slide/tape programs have become one
of the most widely used media for independent
study. The recent introduction of a rear screen
slide viewer in combination with a slide-synchro-
nizing cassette recorder should greatly increase
the use of slides for independent study.
Manual slide viewers are available at a very low
cost and can be used for viewing small numbers of
slides. They can be used in conjunction with a
tape recorder to provide narration for the slides.
A disadvantage in using the slide viewer is that
it is quite easy for the slides to become dis-
arranged and out of sequence.
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2" x 2" Slide Projector (Automatic and Semi-Automatic)
Manufacturer
Model
Physical
1. Operational controls
a. remote advance and reverse
b. remote focus
c. local advance and reverse projector
d. timer for automatic advance
2. Focusing of slides
a, manual
b. automatic focus
3. Pre-heating of slides to reduce tendency of slides to go out of
focus when projected.
4. Can be synchronized for automatic advance with Slide-Sync recorder.
5. Permanently attached grounded power cord.
6. Elevation control adequate without additional props.
7. ¦ Leveling facilities.
8. Blower keeps parts touched in operation cool with sustained operation.
9. Noise level of projector during operation does not interfere with
speaking or listening.
10. Motor and lamp switch(es) provide for operating motor after lamp has
been turned off for cooling projector.
11. Slide trays
a. compatible with existing equipment
b. compatible with materials available
c. easily available
d. can be used to store or distribute slide units
e. capacity
f. accepts glass mounted slides
Combination 2" x 2" Slide and Filmstrip Projector (Manual and Semi-Automatic)
12. Designed to facilitate quick foolproof change from using filmstrips
to using slides or reverse.
13. Can be adapted to use of slide tray.
14. Can be used for single slides only.
15. Automatic take-up of filmstrip.
Optical
1. High and low level light output to adjust screen illumination to slide
density or image size.
2. Various focal length lenses available.
3. Illumination of image (brightness) on screen in setting(s) in which
it is to be used
a. classroom
b. auditorium
c. individual viewing
4. Center to corner brightness of 'image on screen (recommended not more
than 2 to 1),
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16-VOLUME III
SOUND FILMSTRIP PROJECTORS AND VIEWERS
The sound filmstrip has been around for some time,
but its popularity has increased markedly in the
past few years. The increase generally can be
attributed to the trend toward individual use of
media and the development of compact, rear screen,
sound filmstrip viewers which permit easy individual
use of this medium. A major development in sound
filmstrips has been a shift from disk recording to
cassette recording as the audio source.
Although the sound filmstrip can be used with any
compatible filmstrip projector and a record player
or tape recorder, sound filmstrip projectors which
incorporate both these items permit easier use of
this kind of material. These projectors are
designed commonly to provide for automatic advance
of the filmstrip by an inaudible signal on the
recording. The projectors also permit manual ad-
vance of the filmstrip to accommodate sound film-
strips which do not have inaudible advance signals.
Most sound filmstrips have both audible and in-
audible advance signals so they can be used with
both manual and automatic advance projectors or
viewers. Sound filmstrip projectors generally
are designed to be used in small settings and have
relatively low level light output. For large
settings such as an auditorium, sound filmstrips
should be used with a filmstrip projector with
high level light output (500-750 watts) and a
separate audio source.
The rear screen, sound filmstrip viewers now
available are considerably more compact and portable
than previous models. These can be purchased as
viewers only or as a combination filmstrip viewer
and cassette recorder or player. They are available
with both manual and automatic advance capabilities.
The relative inexpensiveness of rear screen, sound
filmstrip viewers; their compactness and portability;
and the ease of storage of large amounts of visual
material on filmstrips are likely to dictate the
continued popularity of this medium.
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Sound Filmstrip Projectors and Viewers
Manufacturer
Model
P -- Projector V -- Viewers
P-V 1. Illumination of image (brightness) on screen for setting(s)
in which it is to be used
a. classroom
b. auditorium
c. individual viewing
P-V 2. Headphone output jack.
P-V 3. Automatic advance signal compatible with existing equipment owned.
P-V 4. Automatic advance signal compatible with materials available.
P-V 5. Automatic advance signal can be recorded locally.
P-V 6. Filmstrip can be advanced manually.
P-V 7. Ampifier output satisfactory for setting(s) in which it is to
be used.
P 8. Can be remotely operated.
P 9. Various focal length lenses available.
P-V 10. Pause control provided.
V 11. Rear screen large enough for viewing by
a. individual
b. small group
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18-VOLUME III
OVERHEAD PROJECTORS
There are several manufacturers and models of over-
head projectors. Although the models all work on
the same principle and utilize the same materials,
they differ in a variety of easy to fit personal
preferences and to match the requirements of dif-
ferent settings in which the projector is to be
used. These projectors may range in price from
$150 to $350. The differences include such things
as: (1) quality of the optical system, (2) light
output (screen illumination), (3) glare-free pro-
jector stage, (4) fold-up projectors for maximum
portability, (5) options such as automatic projection
lamp control (when a transparency is placed on the
stage of the projector, the lamp turns on; when the
transparency is removed, it turns off), and (6)
semiautomatic lamp change. As one would expect,
projectors which have these features are more ex-
pensive, but the added cost may be justified in
increased efficiency of operation and flexibility.
The overhead projector has definite advantages in
instruction: (1) materials can be developed easily
to fit particular needs; (2) it can be used in a
lighted room, permitting other media such as models,
charts, etc., and other activities such as demon-
strations to be carried on in conjunction with the
use of transparencies; (3) it provides active
participation for the person using the equipment;
(4) it is used at the front of the room permitting
continuous eye contact between the presenter and
the viewers; and (5) an almost infinite variety of
techniques and types of transparencies can be
utilized. Materials for making simple but effective
transparencies, such as felt tip pens, transparent
and opaque grease pencils, and dry transfer letters,
are readily available and relatively inexpensive.
Most office copy equipment can be used to reproduce
printed materials onto transparencies for use on
this projector.
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Overhead Transparency Projectors
Manufacturer
Model
Physical
1. Format
a. stage will accept all standard sizes of masks and
transparency areas (10" x 10")
b. will accept acetate roll attachment
c. registration (positioning) system for locating mounts
on projector stage
d. registration system adjustable to fit different size
transparency mounts
2. Portability
a. projector folds-up to luggage size with handle for
carrying
b. weight
c. suitable facilities provided to use as a handle for
carrying
3. Safety
a. permanently attached grounded power cord
b. exposed parts remain cool with sustained operation
c. safety interlock to turn power off when lamp access door
is opened
d. lamp changing possible without hazard to operator,
4. Noise level of fan does not interfere with listening or speaking.
5. Separate switch or switch positions for motor and lamp to permit
cooling off projector without lamp being on.
6. Thermo switch provided to allow projector to cool to desired
level before fan shuts off.
7. Storage space provided for extra lamp.
8. Accessory outlet provided.
9. Corner position of post supporting projection lens for maximum
flexibility in using multiple overlays,
10. Image can be raised sufficiently on screen without tilting
projector.
11. Lamp changed manually.
12. Lamp changed semi-automatic.
Optical
1. Illumination of image (brightness) on screen for setting(s) in
which it is to be used
a. classroom (2000 lumens)
b. auditorium (4000 lumens)
2. Light drop off at edges of screen not more than 1/2 of light
in center.
3. Sealed optics.
4. Resolution of image.
5. Glare free projector stage.
6. Various focal length lenses available.
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20-VOLUME III
TAPE RECORDERS (REEL-TO-REEL AND CASSETTE)
Criteria for selection of both reel-to-reel and
cassette recorders are nearly the same, and except
where indicated, the same criteria can be applied
to both. Reel-to-reel recorders have been around
for nearly 25 years, and there are many excellent
recorders available in various price ranges.
Cassette recorders are relatively new, and the
vast majority of those manufactured have been
aimed at the mass consumer market. They range
in price from less than $20 to $120. These
cassette recorders, in general, have not been
designed for sustained use and should not be
purchased with intended sustained use over long
periods. At this writing there are several
companies manufacturing equipment of sufficient
quality to be operated under sustained operating
conditions. This equipment is available through
audio-visual dealer outlets. Although the cost
may be somewhat higher for this equipment, its
purchase could be justified in terms of reli-
ability, easier maintenance, and lower repair
costs if the equipment is to receive heavy use.
For occasional use the small cassette recorder,
which is widely available, is satisfactory. The
advantages of the cassette system are that the
players are relatively inexpensive and could be
made available for students' home use or on the
job, and the units are simple to operate and
require little technical skill to operate. High
speed cassette duplicators are now available for
less than $1,000, making it economically feasible
to reproduce cassette tapes in any quantity needed.
NOTE: A number of cassette recorders are now
available which can be programmed with an
inaudible signal to automatically advance
slide and filmstrip projectors and rear
screen slide and filmstrip viewers, and to
program the operation of 8mm projectors.
It seems that a 1,000 cycle signal on a
separate audio track is emerging as the
standard for recorders capable of such
programming. This should be kept in mind
when selecting cassette recorders for this
purpose.
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Tape Recorders (Reel to Reel and Cassette)
Manufacturer
Model
R -- Reel to Reel C -- Cassette
R 1. Operates at 3 3/4 and 7 1/2 IPS.
R 2. Operates at 1 7/8, 3 3/4 and 7 1/2 IPS.
R 3. Threading simple to perform.
R 4. Track (record-playback head) configuration
a. half track monaural
b. quarter track monaural
R 5. Maximum reel size of 7 inches.
R-C 6. Jacks provide for:
a. microphone input
b. phonograph or radio input
c. external speaker
d. pre-amplifier output
e. earphone or monitor
R-C 7. Digital counter.
R-C 8. Portability
a. weight
b. cover or case to carry accessory items
R-C 9. On-Off switch for monitor speaker.
R-C 10. Pause control,
R-C 11. Automatic shut off at end of tape.
R-C 12. Standard 1/4" headphone jack.
R-C 13. Automatic record level,
R-C 14. Recording and playback heads easily accessible for cleaning.
R-C 15. Operates from foot pedal.
C 16. Recording and playback heads can be realigned.
C 17. End of tape alarm,
C 18. Operates with various brands of cassettes.
C 19. Built in AC adapter (operates with conventional power cord).
C 20. External AC adapter required for using AC power.
C 21. Can be battery operated.
C 22. Drive belts of durable material.
C 23. Switch provided on microphone for starting and stopping machine
in either record or playback mode.
C 24. Can record inaudible control signal for advancing semi-automatic
slide and filmstrip projectors.
Audio
R 1. Frequency response 50 to 14000 cps at 7 1/2 IPS.
R-C 2. Less than 0.5 wow and flutter.
R-C 3. Audio output sufficient to drive external speakers.
R-C 4. Signal to noise ratio not less than 45 db.
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22 - VOLUME III
VIDEO TAPE RECORDERS
Selecting a video tape recorder has and will con-
tinue to be a difficult task. A study conducted
by the Educational Product Information Exchange
indicates that many people who purchased video
tape recorders have been dissatisfied with their
selection. This dissatisfaction generally has
resulted from the unreliability of the video tape
recorders selected. The problem has been wide-
spread and not associated with any particular
brand or model of recorder.
In addition to the problem of reliability has been
that of compatibility. This problem has been com-
pounded by the introduction of the cassette video
tape recorder. This incompatibility results from
the inability to play a tape recorded on one brand
of equipment on similar equipment of another manu-
facturer. The problem was partially solved when
the EIAJ format was accepted for all 1/2" helical
scan recorders. However, tapes produced on these
machines are incompatible with machines manu-
factured before the acceptance of the EIAJ format.
There is still no standard for 1" helical scan
recorders, and each brand can play only tapes
produced on recorders of the same brand.
The cassette video tape recorder with its ease of
operation will become the major type of recorder
used in industry and education for training pur-
poses. One-inch helical scan recorders and 2"
broadcast quad-head recorders will continue to be
used in studio productions for making master tapes
because of higher production quality for these
types of equipment. The problem of compatibility
has not been solved with cassette video tape
recorders. There is no assurance that the format
presently being used will ultimately be the
standard format. At this writing the 3/4" "U"
format has an excellent chance of becoming a
standard because it is presently being used by
major producers of the machines being distributed
in this country. The 1/2" cassette or cartridge
video tape recorders are using the standard EIAJ
format, thus, making tapes produced on 1/2" reel-
to-reel recorders using this format compatible
with these cassette recorders.
Large companies like Sears Roebuck and Packard Bell
have introduced cassette video tape recorders and
cameras into their consumer product line. Probably
all other manufacturers of television sets for the
home will follow suit. It is too early to tell
what effect the introduction of video cassette
recorders for home use will have on the ultimate
decision about a standardized format, but the
market should be watched closely. In addition,
one manufacturer has introduced video players
which use a disk recording rather than tape. What
potential effect this may have cannot be ascer-
tained .
Selecting a video tape recorder will continue to
be difficult. Following are factors which should
be considered in selecting a video tape recorder:
Ease of Operation
Can the equipment be operated easily by the person (s)
who will be using it without special training?
Availability of Service
Dealer service is a most important consideration un-
less trained technicians for maintenance and repair
service are available to the owners of this equipment
through their own organization. Video tape recorders
are sensitive and sophisticated electronic equipment
requiring service by trained technicians. An organi-
zation which owns a number of video tape recorders
may find it advisable to employ a technician who
will be working on their equipment. Another concern
is whether the service agency has available sufficient
parts to prevent long delays in repair of equipment.
Ease of Maintenance
Are those parts of the recorder which need routine
maintenance easily accessible without having to
disassemble the entire machine? Can this routine
maintenance be accomplished by someone without special
training?
Picture Quality
Image stability, good resolution, accurate color
reproduction. Is the image stable; i.e., does it
maintain continuous quality free from noticeable
deterioration? Does the recorder produce an image
with satisfactory resolution (the ability to repro-
duce fine detail in the material picked up by the
camera)? Resolution will be affected by the quality
of the camera and the lens used in initially
recording the picture. If the machine is capable
of recording color, does it accurately reproduce
color?
Size and Weight (Portability)
If the recorder is to be moved about, is the weight
such that it can easily be carried by one person?
Are provisions made on the recorder for transporting
it, such as handles and a cover for protecting the
exposed parts of the machine? If the machine is to
be used in a study carrel, is it small enough to
fit into the carrel along with a television receiver
and still provide room for the viewer to take notes,
etc.?
Reliability
Will the recorder operate satisfactorily over long
periods with only routine maintenance? This is an
important question for which a satisfactory answer
is difficult to obtain, for the present cassette
video tape recorders have not been on the market
long enough to provide that information. In the
past reliability has been the major concern when
making purchases of this equipment. However, it
is important to note that reliability may be directly
related to the quality of routine maintenance and
the skill of the person(s) operating the equipment.
Compatibility (Interchangeability)
Can tapes produced on one model be used with other (continued)
models by the same manufacturer or different manu-
facturers? Is the equipment compatible with other
equipment owned, or do programs previously recorded
have to be duplicated in a new format? (At some
point it may be necessary to change format, for
example, when moving from reel-to-reel recorder to
a cassette recorder.) If programs are to be ex-
changed with other organizations, compatibility is
an extremely important consideration.
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Video Tape Recorders (Reel to Reel and Cassette)
Manufacturer
Model
1. Compatibility of format with existing equipment owned.
2. Compatibility of format with materials available.
3. Ease of operation.
4. Availability of service,
5. Ease of maintenance.
6. Picture quality
a. image stability
b. resolution
c. color reproduction
7. Portability
a. size
b. weight
c. provisions for carrying
8. Reliability.
9. Features and options
a. can be connected directly to standard television
receiver (RF output)
b. can be used to feed RF modulator (video output)
c. color and monochrome record and playback
d. monochrome record and playback
e. electronic editing
f. battery operated
g. amplifier output jack for external speaker
h. separate audio track recording capability
i. stop motion
j. slow motion
k. built in RF tuner
1, two audio tracks
m. remote control operation
n. rewind speed
o. fast forward speed
p. digital counter
q. automatic shut off at end of tape
r. automatic gain control for video recording
s. automatic gain control for audio recording
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24-VOLUME III
Features to Consider in Selecting Video Recording Equipment
1. Capability of being connected directly to a
standard television receiver (RF Output).
2. Capability of being used to feed RF modulator
(Video Output)
3. Color capability (ability to record and repro-
duce both color and black-and-white television
signals).
4. Electronic editing capability (electronic
editing device which provides for assembly
of a final program from live or prerecorded
segments).
5. Battery operated (ability to be operated with
DC battery supply only).
6. Audio output for external speaker (provides for
use with a large group or to feed a public
address system).
7. Separate recording capabilities for audio track
(provides for recording audio track after the
video image has been recorded).
8. Stop motion or slow-motion capability (can be
used for activity of motion analysis).
9. Built-in tuner for recording off the air without
being connected to a receiver.
10. Provision of two audio tracks (allows for
recording a sound audio track without disturbing
the original track).
11. Remote operation capability (may be desirable if
one person must handle several operations).
12. Rewind speed fast enough to allow satisfactory
rewind time.
13. Fast forward capability (allows for fast location
of materials on tape).
14. Digital counter (provides for accurately noting
location of materials on tape for future reference
in finding them).
15. Automatic shutoff at end of tape (this turns off
power to the record-playback mechanism at the end
of the tape in either record or playback mode,
thus minimizing potential damage to the tape and
the record-playback mechanism of the recorder).
16. Automatic gain control for audio and video recording
(this capability makes it unnecessary for the
operator to adjust manually audio and video re-
cording levels as input signal levels change during
recording).
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References
Anon. 1967. Audiovisual Equipment Evaluations and
Qualitative Guidelines for Equipment. State
of Hawaii, Department of Education.
Brown, James W., Richard B. Lewis, and Fred F.
Harcleroad. 1969. AV Instruction, Media and
Methods, 3rd edition. McGraw-Hill, New York,
p. 529-S5S.
Brown, James W. and Kenneth Norberg. 1965. Admin-
istering Educational Media. McGraw-Hill, New
York, p. 102-119.
EPIE. 1968. 8mm Silent and Sound Projectors, Vol.
2, No. 2, Educational Product Report. EPIE
Institute, New York.
EPIE. 1969a. 8mm Silent and Sound Projectors,
Vol. 3, No. 3, Educational Product Report.
EPIE Institute, New York.
EPIE. 1969b. Helical Scan Video Tape Recorders,
Vol. 3., No. 3, Educational Product Report.
EPIE Institute, New York.
EPIE. 1970a, Helical Scan Video Tape Recorders,
Vol. 3, No. 4, Educational Product Report.
EPIE Institute, New York.
EPIE. 1970b. Audio Cassette Tape Recorders, Vol.
3, No. 5, Educational Product Report. EPIE
Institute, New York.
EPIE. 1971. Overhead Projectors, Video Cassettes,
Report No. 39, Educational Product Report.
EPIE Institute, New York.
EPIE. 1972. 16mm Motion Picture Projectors.
Report No. 43, Educational Product Report,
EPIE Institute, New York.
Laird, Dugan. 1973. A User's Look at the Audio-
visual World. National Audio-Visual Associa-
tion, Inc., Fairfax, Virginia, 38 p.
North Carolina Department of Public Instruction.
1972. Purchaser'a Guide for Projectors and
Related Equipnent. North Carolina State
Department of Administration.
Wyman, Raymond. 1969. Media Ware, Selection,
Operation and Maintenance. Wm. C. Brown,
Dubuque, Iowa.
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