University Archives

Minnesota Educational Media Organization (MEMO) Equipment Archive

The MEMO Equipment Archive is a collection of early to recently-outdated audiovisual equipment used in Minnesota Schools and Colleges before the Internet and microcomputers consolidated audiovisual presentations into unified, digital-based technologies, all produced and presented by computer-based equipment. This archive provides the visitor with a look into the past, where each presentation mode required a separate piece of equipment, and it provides the seasoned professional with a perspective by which to appreciate, or, perhaps criticize, contemporary technologies.

We are grateful to both individual and institutional members of the Minnesota Educational Media Organization (MEMO), for their donations of audiovisual equipment to this archive.

This archive has been organized into three sections. Please visit each section for a chronological series of media devices.


The photographs and descriptions represent the best available information regarding the equipment exhibited. If you can provide additional information or corrections for the inevitable errors that might occasionally creep in, please contact University Archives.


Edison Model "B" Cylinder Phonograph

Edison’s National Phonograph Company, Camden, New Jersey, c. 1888 – 1903

This phonograph was fitted with the Model ”C” reproducer, which played two-minute wax cylinders. The machine would also play four-minute cylinders when fitted with a Model “H” reproducer. The “Thomas A. Edison” trademark is visible on the bedplate of the phonograph.

Donated by M. I. Smith, 1971

Edison Edison

Cameo Model CB Dictaphone

Dictaphone Corporation, New York, N. Y., c. 1918 -1920

The development of electronic dictation technology that supported the business community also created the need for transcribing specialists. Schools, colleges, and other training facilities used this technology to prepare students for careers as "Dictaphone secretaries."

Donated by M. I. Smith, 1971

Cameo Cameo

"Soundmirror" Magnetic - Tape Recorder

The “Soundmirror” Magnetic Tape Recorder was manufactured by the Brush Development Company in Cleveland, Ohio between 1949 and 1953.

The recording medium was a continuous loop of steel tape. The recording period for each tape was approximately two minutes.

Donated by AVCAM, 1988

Soundmirror Soundmirror

Victor Victrola Phonagraph

Victor Talking Machine Company in Camden, New Jersey, c. 1915 – 1923

These phonographs were identified as “lidless external – horn Victors” because of where the manufacturer located the sound box and horn assembly. The machines were designed to play a flat, disc record, which revolved at 78 rpm.

Donated by M. I. Smith, 1971


Webster - Chicago Wire Recorder

Webster – Chicago Company, Chicago, Illinois, c. 1945 – 1952.

This technology was first used by the military during World War II. After the war, Webster – Chicago began manufacturing wire recorders for the civilian market until magnetic tape made wire recording obsolete.

Donated by St. Cloud State University, 1988

Webster Webster

Freed-Eisemann Educator FM-AM Radio

Freed Radio Corporation of New York, N.Y.

Educators could enrich their curriculum beyond the resources of any single school through the incorporation of radio broadcasts. This Educator model radio was especially designed to play over public address systems, making it a valuable resource for classroom use.

Donated by MEMO, 1988.

Freed Freed

RCA Wire Recorder

Radio Corporation of America, New York, NY, early 1940's.

This recorder was designed to support instruction by recording sounds for immediate playback. A reusable plug-in cartridge, loaded with a fine, steel wire recording medium, recorded up to one-half hour of information.

St. Cloud State University, 1988.

RCA Wire RCA Wire


Kodak View Camera

No description available.

Kodak Kodak

New Combined Balopticon Opaque Projector

Bausch and Lomb Optical Co., Rochester, New York, c.1915.

The New Combined Balopticon projected lantern slides and opaque objects. A 1000 watt gas filled mazda lamp provided the required illumination for this projector to be used in large auditoriums.

Donated by M. I. Smith, 1971.

Balopticon Opaque Projector Balopticon Opaque Projector Balopticon Opaque Projector Balopticon Opaque Projector

Universal Balopticon Opaque/Slide Projector

Manufactured by Baush and Lomb Optical Company, Rochester, New York, 1914 - 1918.

The Universal Balopticon was a versatile projector. The dual lens feature of the machine allowed users to easily alternate between opaque objects and lantern slides during a presentation. When equipped with a slidefilm attachment, strip films could also be projected with the Universal Balopticon.

The Universal Balopticon is about three feet long, almost two feet high, and weighs over thirty pounds. Designed for use in auditoriums and large classrooms, it has a heavy power cord and a large switch, neither of which would meet current electrical standards and codes. The lamp, missing from the white, ceramic socket in the rear compartment, could be moved along its adjustment rod to provide optimum image quality. Though the rear compoartment was hot enough to literally burn up insects, moths that entered the front compartment housing the deflection mirror simply dehydrated. The moth in the photo at left could easily have entered a class lecture well before most of us were born.

Donated by M. I. Smith, 1972.

Balopticon Opaque/Slide Projector Balopticon Opaque/Slide Projector

Balopticon Opaque/Slide Projector

Bausch & Lomb Optical Co., Rochester, New York, c. 1938.

The versatility of this Balopticon projector allowed educators to project lantern slides and films, photographs, and actual objects.

Donated by M. I. Smith, 1971

Balopticon Opaque/Slide Projector Balopticon Opaque/Slide Projector

Kodascope Model E 16 mm Silent Projector

Eastman Kodak Corporation in Rochester, New York, c.1937.

Many athletic departments used 16mm silent film for recording purposes. The Kodascope Model E 16 mm Silent projector was used to review film footage of athletic events.

Donated by St. Cloud State University, 1988

Kodascope Kodascope

Beseler Model OA3 Opaque Projector

Charles Beseler Company, New York, N.Y.

Opaque projectors, like the model OA3, were very popular with teachers because they could projector a wide variety of materials, from graphics to actual objects, without tedious preparatory work

Donated by Owatonna High School, 1988

Beseler Beseler

McIntosh Portable Sciopticon

Baush & Lomb Optical Co., Rochester, New York, c. 1912.

This Sciopticon projector was used to project lantern slides. A mechanical-feed, carbon- arc lamp provided the illumination.

The carbon arc lamp was temperamental; it required constant attention from the operator, often flickered in a "strobe-like" manner, and when it went out, it had to be restarted by allowing the carbon rods to touch momentarily to restore the arc. Even so, it was the brightest lamp available at the time. Unfortunately, it also required a lengthy optical path to avoid burning the materials being projected.

Donated by M.I. Smith, 1972

McIntosh Portable Sciopticon McIntosh Portable Sciopticon

McIntosh Stereopticon Opaque & 4 x 4 Slide Projector

Baush & Lomb Optical Co. in Rochester, New York. Manufactured between 1931 – 1933.

The McIntosh Stereopticon projector was designed to project 4" x 4" slides and opaque objects. The ability to change between projection formats was a unique feature of this machine.

This Stereopticon has no lens for the opaque mechanism, and might well never have had one. No doubt many classrooms, especially in biology and medicine, used the projector exclusively for the 4x4 slide, which could be produced by artists in full color long before the availability of quality, photographic color slides.

The slide shown at left is labeled, "Anatomy - The Digestive Organs in Place."

Donated by M. I. Smith, 1971.

McIntosh Stereopticon McIntosh Stereopticon

Stereoscope Hand-held Viewer

Keystone View Company

In the early 1900’s the Stereoscope Hand-held Viewer was used for individual viewing of pictures mounted on stereocards. Viewing stereocard images through a stereoscope projector provided the viewer a three-dimensional image, and often their only connection with far-away places typically depicted in the viewer.

The Stereoscope was not only a popular device for schools, but many libraries and homes had stereoscopes for entertainment and education. Many libraries had cabinets containing hundreds of stereoscope frames, and travel photography via a stereoscopic camera was a viable business at a time when television was only a dream and few people traveled more than a few miles from their homes.

Stereoscope  Stereoscope

Spencer Model D Delineascope

Baush & Lomb Optical Company, Rochester, New York, early 1930’s.

This Spencer Delineascope projected both 2" x 2" and 3 " x 4" color slides by means of an interchangeable condensing lens system. These projectors were used in large auditoriums as well as traditional sized classrooms.

Donated by AVCAM, 1975

Spencer  Spencer

Spencer Model SA Opaque/Lantern Slide Delineascope

Spencer Lens Company, Buffalo, New York

A dual lens system allowed this machine to project both opaque objects and 4" x 4" lantern slides.

Donated by M. I. Smith, 1971.

Spencer  Spencer

Tri-Purpose Picturol Projector

Society for Visual Education, Inc., Chicago, Illinois, c. 1943.

The Tri-Purpose projector was designed for projecting single or double-frame filmstrips,and 2" x 2" slides. During World War II, the Tri-Purpose projector was given to schools that were involved with pre-induction training courses.

Donated by St Cloud State University, 1988.

Tri-Purpose Tri-Purpose

Viewlex Filmstrip/Slide Projector

The Viewlex Inc. Company, Long Island, New York.

The Viewlex projected slides and filmstrips. It used an aspheric condenser system with a 150 watt projection lamp, which, according to the manufacturer, provided greater screen brilliance than other projectors using 300 watt lamps.

The relatively modern Viewlex represents the ultimate version of the multipurpose projector. Its efficient optical system allowed compact design, easy operation, and quality images. Teachers could use either 35mm slides or 35mm filmstrips simply by rotating the lens housing and inserting the appropriate transport mechanism.

Donated by SCSU, 1988.

Viewlex  Viewlex  Viewlex  Viewlex


New Premier 9.5mm Movie Projector

The Pathescope Company of America in New York, N. Y., c. 1917 – 1920

This motion picture projector was very simple in design. The narrow width, 9.5mm, film was in plain sight during projection. The price of the machine complete with wiring, carrying-case, and 4 - 6’ screen was $175.00.

Donated by M. I. Smith, 1971