Translation guide
Morse code is a system of dots and dashes used for communication. In Japanese, it is referred to by a loanword or a native term, and is understood as an international code.
Referring to Morse code as a system of dots and dashes.
The most common term for Morse code in Japanese. 'モールス' is from 'Morse', and '信号' means 'signal'.
He sent a Morse code message.
Onomatopoeic representation of the dots (トン) and dashes (ツー) in Morse code. Used informally or in explanations.
Also common, using '符号' (code/sign) instead of '信号'. Slightly more technical.
Learning Morse code is difficult.
SOS is dot-dot-dot, dash-dash-dash, dot-dot-dot.