Use of "Q Codes" and other codes on wireless in 1912 ?

May 3, 2005
Were "Q Codes" in use by Marconi Operators in 1912 ?

There was a discussion about the use of "DDD" and "QRT" previously.
As I interpret it, "DDD", as Phillips sent it, meant "To Californian ! YOU stop sending immediately ! I am working Cape Race !" Evans received the "DDD" and there was no need for an acknodgement. He simply shut down.

Was "DDD" a code just used by Marconi Operators ?

In Amateur Radio "QRT" usually means "I am going to shut down my station". This usually means he is shutting down his whole station - He will not be transmitting or receiving.
"QRT?" (QRT with a question mark) Is a question from one station to another "Shall I shut down my station ?" and would require a reply as to "Yes" or "No". ?

Question was if such use of "QRT" would have been in use in 1912 ?

These "Q Codes" are used on voice transmissions (I guess a bit informally) on Amateur Radio. You will hear this, for example:
"Well, it's getting late and I am going QRT for the night."
"My QTH (location) is ...........°
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Alex F

Nov 8, 2013
Compare with RRR, TTT, XXX, DDD...

DDD SOS was used in Morse Telegraphy before sending SOS distress relay message later on, till 1995.

It is simple repetion of "D" in Morse Telegraph language. "R" means "received". RRR - sending three times is just to repeat R.

"RD" was used instead of "R" by the Titanic.

Compare with CQD, QSD, LID meaning in Telegraph language ethymology. LID - an operator who can not LSN (listen) :)

"D" was used as "deferred" in some old abbreviations. T - "hear you" (stop calling, reply on A), A - "calling you"... X - "signal" etc