The Phonetic Alphabet is an important adjunct to long-range communications

The Phonetic Alphabet is an internationally recognised set of words used to help communicate when language differences or band conditions are inhibiting effective communication. A typical example might be:

“My name is Harry, Hotel, Alpha, Romeo, Romeo, Yankee”. This would help clarify where the other station might think your name is Barry, or is simply having troubles copying your signal.

You are not required to know the Phonetic Alphabet for the examination, but it is important to be aware of this word-set as it remains in common usage around the world

Note that you use the phonetic alphabet to spell your call sign and name completely. Do not use a mixture of plain language and the phonetic alphabet, as that will lead to confusion.

Unless signals are very poor in readability, it is not normal practice to use the Phonetic Alphabet on VHF/UHF FM transmissions, direct or via repeater.

Historically, there have been several variants of this alphabet. 

For clarity, Amateur operators should stay with the official NATO version (below)   

According to a Wikipedia article, These code words have been stable since 1956.   

A 1955 NATO memo stated that:

It is known that [the spelling alphabet] has been prepared only after the most exhaustive tests on a scientific basis by several nations. One of the firmest conclusions reached was that it was not practical to make an isolated change to clear confusion between one pair of letters. To change one word involves reconsideration of the whole alphabet to ensure that the change proposed to clear one confusion does not itself introduce others.

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ACMA Syllabus Extract

The Phonetic Alphabet does not appear on the Foundation Level syllabus, but it does appear on the Standard and Advanced syllabus and it is examinable content in those exams.

According to the Foundation Syllabus document, it is sufficient to be aware that various recognised abbreviations are in common use internationally.

8.8 Abbreviations

Recall that there are internationally recognised abbreviations commonly used in communications.

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