Commercial  service and  sos  distress  call

By 1912, when Francis A. Collins' The Wireless Man was published, all the major passenger liners were equipped with radio transmitters. In the opening chapter of this book, Across the Atlantic, Collins reviewed how radio now kept vessels on transatlantic voyages in nearly constant communication with shore stations and each other. Initially large passenger liners were the primary commercial ocean-going vessels to install radio transmitters. But in the 1913 edition of Marconi's annual The Yearbook of Wireless Telegraphy and Telephony, Wireless Telegraphy and the Mercantile Marine promoted the money-saving benefits of radio for smaller ships, proclaiming that "Wireless telegraphy is now recognized as an essential part of the equipment of ocean-going passenger vessels, and, to a rapidly increasing extent, of cargo vessels and smaller craft." The 1916 edition of Brown's Signaling noted that "Any book dealing with signaling in general is incomplete without a reference to wireless telegraphy which, for mercantile signaling, offers so many advantages over other methods of signaling" in its The Quenched Spark System section, which featured a shipboard installation offered by Siemens. The General Information covered the basics for operating a Marconi shipboard radio installation, in part noting that "Nothing is more irritating than to find, when the point of a pencil suddenly breaks, that there are no sharpened pencils in reserve."
In 1905, the distinctive Morse code character string ...---... (SOS) was adopted by Germany for signifying distress. (A German-language account of the adoption of the April 1, 1905 regulations appeared in the April 27, 1905 issue of Elektrotechnische Zeitschrift: Regelung der Funkentelegraphie im Deutschen Reich). In 1906, SOS was adopted at the Berlin Radiotelegraphic Convention as the official international standard for distress calls, although Marconi operators in particular were slow to conform -- G. E. Turnbull's Distress Signaling, from the 1913 edition of the annual The Yearbook of Wireless Telegraphy and Telephony, noted that the Marconi companies had adopted "C.Q.D." as a distress signal in 1904, only to have it supplanted by the international ratification of "SOS" two years later. Turnbull reports that even after this some of the old-time Marconi operators continued to use C.Q.D. for a time, although "The change of the call letter is, however, a sentimental regret, and 'C.Q.D.' is being gradually forgotten." However, in 1909 not all the Marconi operators had made the switch, reflected by the title of Alfred M. Caddell's article about sinking of the Republic, C Q D, which appeared in the April, 1924 issue of Radio Broadcast magazine. The February, 1909 issue of Modern Electrics printed a transcript of radio communication related to this event in Operator Binns' Wireless Log. And a review by Baltic Captain J. B. Ranson of the twelve long hours it took to find the Republic, The Triumph of Wireless from the February 6, 1909 issue of The Outlook, included Ranson's opinion that, due to recent scientific advances -- especially radio communication -- "the passenger on a well-equipped transatlantic liner is safer than he can be anywhere else in the world." (Because three-dashes in American Morse stood for the digit "5", unlike International Morse where it stood for the letter "O", in some U.S. practice the distress signal was referred to as "S5S", for example, "S 5 S" Rivals "C Q D" for Wireless Honors, from the February, 1910 Popular Mechanics.)