Marine Radio - some historical background

Radio was first installed on ships around the turn of the 20th century.

In those early days, radio (or "wireless", as it was known) was used primarily for transmission and reception of passenger telegrams.

Radio watchkeeping hours were not standardised, and there was no regulatory requirement for carriage of radio by ships.

Indeed, there was a general lack of any sort of regulation of the radio spectrum. Amateur/experimental stations often interfered with commercial stations and vice-versa.

All that changed one clear and cold April night in 1912.....

The most modern passenger liner of the time, the RMS Titanic, sank on her maiden voyage after a collision with an iceberg.

Some 1500 people were killed in the disaster. Fortunately, 700 odd people were saved, thanks mainly to the efforts of the Titanic's two Radio Officers, who managed to summon help from nearby vessels.

However, the vessel closest to the disaster (the Leyland liner Californian) could not be summoned, as her Radio Officer had just gone off watch after 12 hours on duty. The Californian managed to establish communications with other searching vessels after the Titanic had sunk. But by then, it was too late - one thousand five hundred people, including the cream of American and European society, had frozen to death in the icy North Atlantic.

The Titanic disaster brought about a number of fundamental changes to Marine Radio:

• carriage requirements and radio watchkeeping hours were standardised;

• message priorities were standardised - ie: distress and safety traffic always has priority over commercial traffic;

• distress frequencies were standardised; and

• radio silence periods were introduced.

The Titanic disaster also served as the catalyst for the introduction of the International Convention for the Safety of Life At Sea (the SOLAS Convention). The introduction of the first SOLAS Convention was delayed by WW1 - it came into force in the 1920's.

For more detailed information on the radio aspects of the Titanic, have a look at the RMS Titanic Radio Page.

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During the 1920's, 30's and 40's, marine radio advanced with the technology of the day - radiotelephone operation was introduced, and most importantly, High Frequency (HF) came into widespread use, thereby allowing communications over ever-increasing distances.

Of course, marine radio played a vital role in WW2 - the war provided a great boost to radio technology in general. Amongst other things, WW2 brought direct bridge to bridge communications into being, through the use of what was to be the marine VHF band - known during the war years as "talk between ships" (TBS).

After the war, Marine Radio incorporated the latest achievements in electronics - solid state (ie: transistorised) equipment and Marine Radar became commonplace.

However by the late 1970's, despite tremendous general advances in communications, Morse Code still ruled the marine radio waves.

After some 80 odd years of development, marine distress alerting still relied on a human being sitting in front of a receiver. Ship's Radio Officers sent a distress message using Morse Code (or radiotelephone) in the hope that another ship or shore station would hear the call and respond.

The main Marine Radio distress frequency of 500 kHz had remained unchanged since the Titanic had sent her plaintive calls for help that April night in 1912.......

The stage was set for some significant change....