[Ans] Which three initials comprised the distress call prior to SOS?

Step 1 : Introduction to the question "Which three initials comprised the distress call prior to SOS?"

CQD is one of the first distress signals adopted for radio use prior to SOS. It was established on February 1, 1904 by the Marconi International Marine Communication Company. "CQD" was understood by wireless operators to mean, "All stations: distress." On April 15, 1912, RMS Titanic radio operator Jack Phillips initially sent "CQD", which was still commonly used by British ships. Harold Bride, the junior radio operator, suggested using "SOS", saying half-jokingly that it might be his last chance to use the new code. Phillips thereafter began to alternate between the two. Though Bride survived the sinking, Phillips did not.

[Answer] Which three initials comprised the distress call prior to SOS?

Step 1 : Introduction to the question "Which three initials comprised the distress call prior to SOS?"

...CQD is one of the first distress signals adopted for radio use prior to SOS. It was established on February 1, 1904 by the Marconi International Marine Communication Company. "CQD" was understood by wireless operators to mean, "All stations: distress." On April 15, 1912, RMS Titanic radio operator Jack Phillips initially sent "CQD", which was still commonly used by British ships. Harold Bride, the junior radio operator, suggested using "SOS", saying half-jokingly that it might be his last chance to use the new code. Phillips thereafter began to alternate between the two. Though Bride survived the sinking, Phillips did not.