T2C03 from the 2018-2022 Technician License Course Section 2.3, Call Signs:
T2C03: What should be done when using voice modes to ensure that voice messages containing unusual words are received correctly?
A. Send the words by voice and Morse code B. Speak very loudly into the microphone C. Spell the words using a standard phonetic alphabet D. All of these choices are correct
Receiving and interpreting unusual or infrequently used words and terms can be tricky in some conditions. The same goes for proper names, especially if a non-standard spelling is used. Particularly in an emergency scenario, message traffic must be recorded and passed on with accuracy, exactly as received. With lives and property potentially at risk, precise communication is of paramount concern to the emergency operator.
Poor atmospheric conditions with HF communications, weak signal strength, interference from other stations or emitters, and other environmental factors can degrade the quality of received audio. Even in good conditions many words and alphabetic characters sound very similar. The letters B, C, D, E, G, P, T, V, and Z offer salient examples of similar sounding letters whose differentiation depends strictly upon the beginning phoneme that is commonly comprised of quite high audio frequency components that may not clearly survive the modulation-demodulation process. As this question implies, something must be done to insure voice message traffic is correctly received.
The Response Options:
Option A: Sending the words by voice and Morse Code is not very efficient. And some operators may not be able to interpret Morse Code well.
Option B: Speaking into the microphone loudly will probably just distort the audio due to over driving the microphone amplifier and further exacerbate the problem addressed here.
Option C: Now we’re communicating. Spelling out unusual words, terms, or proper names
Phonetics help produce clear, unambiguous communications.
Using a standard phonetic alphabet works very well to improve communications. So, what is a phonetic alphabet, and particularly a standard phonetic alphabet? (Option D obviously in not applicable given the status of A and B.)
The Rest of the Story:
A phonetic alphabet consists of a word to represent each letter of the alphabet. For instance, ‘A’ is represented by the word ‘Alpha.’ Since words contain more phonemes than letter names, and frequently even multiple syllables, there is redundant audio information transmitted that helps the receiving operator more easily identify or distinguish the letter.
The International Telecommunications Union (ITU) adopted a standard phonetic alphabet in 1959 based upon the preceding phonetic alphabet of the International Civil Aviation Organization (ICAO). These standard phonetics changed and evolved into the adopted standard over the course of a few years following World War II, ensuring their acceptability and uniqueness among international languages.
It is a good idea with international contacts to utilize the ITU standard phonetics rather than alternative phonetics. The international standard phonetic terms are recognizable as such around the world, and they are less likely to be confused for other words or meanings than non-standard phonetics. Using non-standard phonetics can sometimes be confused for other meanings. For instance, I have often heard “Japan” used for ‘J’, “America” for ‘A’, and “Italy” for ‘I’. Usually this does not cause excessive confusion in the proper context, but sometimes these country names may be incorrectly interpreted as the location of the operator. Check out Bob KØNR’s article on alternative phonetic alphabets.
The standard ITU phonetic alphabet is depicted here. You may hear them in the media player at the end of this article.
Particularly in noisy single sideband (SSB) phone mode conditions, operators will use phonetics regularly for station identification, for relating operator name, and location. In contest exchanges phonetics are often used to help specify the Maidenhead grid square location of a station for unambiguous and efficient contest exchanges.
The answer to Technician Class question T2C03, “What should be done when using voice modes to ensure that voice messages containing unusual words are received correctly?" is “C. Spell the words using a standard phonetic alphabet."
-- Stu WØSTU
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