Wiktionary
telegraph code
n. character encoding used to transmit information through telegraphy machines.
Wikipedia
Telegraph code
A telegraph code is a character encoding used to transmit information through telegraphy machines. The most famous such code is Morse code.
Usage examples of "telegraph code".
The Hammerlund loudspeaker on the table behind the Beachcomber suddenly gave out with a burst of high-speed CW, or continuous wave radio telegraph code.
Weldon was starting to speak again when a staccato burst of high speed radio telegraph code made the recorder's speaker cone rattle.
The throbbing was spaced between beats like dots and dashes of the regular Morse telegraph code.
Where would he be without a knowledge of the wireless telegraph code now?