omnigraph

[om-ni-graf, -grahf]
noun
  1. a device for converting Morse Code signals that are punched on a tape into audio signals, used in the training of telegraph operators.

Origin of omnigraph

First recorded in 1860–65; omni- + -graph
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018