The Instructograph was a paper tape-based machine used for the study of Morse code. The paper tape mechanism consists of two reels which passed a paper tape across a reading device that actuated a set of contacts which changed state dependent on the presence or absence of hole punches in the tape.

  This model was kindly donated to the museum and with a bit of TLC it was brought back to life. There is still some work to do on the internal oscillator before the machine is in full working order.

  The contacts could operate an audio oscillator for the study of International Morse Code (used by radio), or a sounder for the study of American Morse Code (used by railroads), or a light bulb (Aldis Lamp - used by Navy ship to ship or by Heliograph).

  The Instructograph was in production from about 1920 through 1983. The first US patent, No. 1,725,145, was granted to Otto Bernard Kirkpatrick, of Chicago, IL, on August 20, 1929. Most of them would be wound by hand or be plugged into a wall outlet. Most plugin outlet based instructographs would have a set of knobs that can control the speed and volume. The latest version of the Instructograph was the model 500 which included a built in solid state oscillator. This model was available to be purchased as new through at least 1986.

  As far as I am aware it was never used in the Royal Navy but I have included it on the website as it is part of the story of Morse Code.

  Several different models were manufactured by the Chicago-based Instructograph Co. from the 1920s all the way into the 1980s. Learning to receive code is generally a more difficult task than learning to send, and this portable device would allow the student to practice code recognition without the aid of an instructor or fellow student.

  Reels of oil-impregnated paper tape perforated with dots and dashes were used to actuate a set of electrical contacts that would in turn operate an external railroad-type sounder, a buzzer or oscillator (for tone), or a light for optical communication. Note that the reel of tape has two sets of Morse perforations. The set of perforations on the bottom of the tape are played when the tape is turned over. The earliest versions of the Instructograph used a wind-up phonograph motor with a variable speed governor to power the rotation of the tape reels.

  Other than the mechanical motor, the only other elements in the device consisted of a set of contacts, a battery, and a rheostat to control the current to the sounder or buzzer. Later versions used a variable speed electric motor for the tape drive, and some actually included an on-board electronic oscillator that would produce an adjustable audio tone. This model uses a wind-up phonograph motor with a variable speed governor to power the rotation of the tape reels. However, it also has an in-built on-board electronic oscillator that would produce an adjustable audio tone. The oscillator is currently not working and will be refurbished in due course. In the meantime the output is fed to a SCOBA morse trainer.

  The machine helped to increase speed and efficiency in sending and receiving Morse code. Its paper tape reels contain code exercises--helpful to those studying for the qualifying exams to become a professional telegraphy operator. Morse code was used extensively throughout the late-19th and 20th centuries for radio and military communication.

Here is a short video of the Instructograph in operation (click on the image to play)

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