Prior to the electrical telegraph, a widely used method of building national telegraph networks was the
The … See more

Early printing telegraphs continued to use Morse code, but the operator no longer sent the dots and dashes directly with a single key. Instead they operated a piano keyboard with the characters to be sent marked on … See more

The teleprinter was invented in 1915. This is a printing telegraph with a typewriter-like keyboard on which the operator types the message. Nevertheless, telegrams continued to be sent in upper case only because th… See more

In 1931, the International Code of Signals, originally created for ship communication by signalling using flags, was expanded by adding a collection of five-letter codes to be used by radiotelegraph operators. See more

1. ^ Left and right are the message sender's left and right. The neutral position is with the flag raised above the signaller's head. Myer's manual specifies the code with the exact opposite movements (Myer (1872), p. 68), A is 2… See more