1) Manipulator 2) Morse-code user 3) Operator 4) Telegraph operator 5) Telegraphist 1) Telegraphist 
• (n.) One who sends telegraphic messages; a telegraphic operator; a telegraphist.
Te·leg'ra·pher noun One who sends telegraphic messages; a telegraphic operator; a telegraphist. 
[n] - someone who transmits messages by telegraph
telegrapher 1. Someone who telegraphs a message or news. 2. The sender of a telegram.
telegraphist noun someone who transmits messages by telegraph