Instructograph
From Wikipedia, the free encyclopedia
The Instructograph was a paper tape-based machine used for the study of Morse code.
The paper tape mechanism consisted 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. 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).[citation needed]