VHF Procedures - General
The efficient use of VHF radio depends to a
large extent on the operator's method of speaking. As the distinctive sounds of consonants are apt to become
blurred in the transmission of speech, words of similar length containing the same vowel sounds may sound alike.
Special care is necessary in their pronunciation.
Special care is also required in handling the microphone. Do not hold
the microphone too close to your mouth because it may cause distortion or slurring of words and you may have to
repeat your message to be understood. Speak all words plainly and end each word clearly in order to prevent the
running together of consecutive words. Avoid any tendency to shout, to accent syllables artificially or to speak
too rapidly. The following points should be kept in mind when using a radiotelephone.
Keep the rate of speech constant, neither too
fast nor too slow. Remember that the operator receiving your message may have to write it down.
Preserve the rhythm of ordinary conversation.
Avoid the introduction of unnecessary sounds such as “er” and “um” between words.
If the communication link is unreliable, or the wording of the text
complex or confusing, use the command WORDS TWICE or, upon request, repeat the message using the phonetic alphabet.
This should ensure that the information within the text of the message is received correctly.
Procedural Words and Phrases
While it is impractical to set down precise
phraseology for all VHF procedures, the following words and phrases should be used where applicable. Words and
phrases such as OK, REPEAT, TEN-FOUR, OVER AND OUT, BREAKER BREAKER, COME IN PLEASE, or slang expressions should
not be used.
Word or Phrase Meaning for VHF Radio
ACKNOWLEDGE Let me know that you have received and understood this message.
AFFIRMATIVE Yes, or
BREAK To indicate
the separation between portions of the message. (To be used where there is no clear distinction between the text
and other portions of the message.)
CHANNEL Change to
channel .......... before proceeding.
CONFIRM My version
is _____. Is that correct?
CORRECTION An error
has been made in this transmission (message indicated). The correct version is
GO AHEAD Proceed
with your message.
HOW DO YOU READ? How
well do you receive me?
I SAY AGAIN Self-explanatory (use instead of “I repeat”).
NEGATIVE No, or that
is not correct, or I do not agree.
OVER My transmission
is ended and I expect a response from you.
OUT Conversation is
ended and no response is expected.
READBACK Repeat all
of this message back to me exactly as received after I have given OVER. (Do not use the word “repeat”.)
ROGER I have
received all of your last transmission.
STANDBY I must pause
for a few seconds or minutes, please wait.
SAY AGAIN Self-explanatory. (Do not use the word “repeat”.)
THAT IS CORRECT Self-explanatory.
Phonetic Alphabet for VHF radio
The words of the International Telecommunication
Union (ITU) phonetic alphabet should be learned thoroughly. Whenever isolated letters or groups of letters are
pronounced separately, or when communication is difficult, the alphabet can be easily used.
When it is necessary to spell out words,
the following table should be used. The syllables to be emphasized are shown in bold type.
Letter Word Pronounced
C Charlie CHAR
LEE or SHAR LEE
Hotel HOH TELL
I I India
IN DEE AH
JEW LEE ETT
N November NO VEM
Papa PAH PAH
Quebec KEH BECK
ROW ME OH
Sierra SEE AIR RAH
YOU NEE FORM or OO NEE FORM
W Whiskey WISS
Example: To report a missing child with the surname Schmidt: SIERRA, CHARLIE, HOTEL, MIKE, INDIA, DELTA, TANGO
Numbers Expressed in Words
0 - ZERO 6 - SIX
1 - ONE 7 - SEVEN
2 - TWO 8 - EIGHT
3 - THREE 9 - NINE
4 - FOUR . - DECIMAL
5 - FIVE ?,000 - THOUSAND
All numbers except whole thousands should be transmitted by
pronouncing each digit separately. Whole thousands should be transmitted by pronouncing each digit in the
number of thousands followed by the word THOUSAND.
10 becomes ONE ZERO
75 becomes SEVEN FIVE
100 becomes ONE ZERO ZERO
5,800 becomes FIVE EIGHT ZERO ZERO
11,000 becomes ONE ONE THOUSAND
68,009 becomes SIX EIGHT ZERO ZERO NINE
The twenty-four hour clock system should be used
in expressing time in the Maritime Mobile Service. It should be expressed and transmitted by means of four figures,
the first two denoting the hour past midnight and the last two the minutes past the hour.
Some examples of time using the twenty-four hour clock system are
shown in Table 4.
Some Times as Expressed by VHF
12:45 a.m. 0045 ZERO ZERO FOUR FIVE
12:00 noon 1200 ONE TWO ZERO ZERO
12:45 p.m. 1245 ONE TWO FOUR FIVE
12:00 midnight 0000 ZERO ZERO ZERO
1:30 a.m. 0130 ZERO ONE THREE ZERO
1:45 p.m. 1345 ONE THREE FOUR FIVE
8:30 p.m. 2030 TWO ZERO THREE ZERO
The calling examples used are sample call signs only.
Before transmitting, listen for a period long enough to ensure that
harmful interference to transmissions already in progress is not likely to occur. If such interference seems
likely, wait until the transmissions in progress are completed before making your call.
A station having a distress, urgency or safety message to transmit is
entitled to interrupt a transmission of lower priority.
Single Station Call
When establishing communications with a specific
station, transmit the call sign of the station being called, followed by the call sign of the station making the
call, as shown in the following example.
Sea Wolf (said once or if communication
conditions are difficult not more than 3 times)
Reverse Calling example - This is Riding Hood calling Sea
Avoid REVERSE calling as this is incorrect procedure.
Remember that the identifier of the station being called is
always spoken first, followed by
THIS IS and your own station's identifier.
When you hear a call directed to your station, reply as soon as
possible. Advise the calling station to proceed with the message by means of the words GO AHEAD, or, if you
are occupied, by saying STAND BY followed by the estimated number of minutes until your reply. Do not ignore
the call. This may result in unnecessary calling, which uses up valuable air time in a crowded
Replying to Calls when Information Is Missing
When you hear a call, but are
uncertain the call is intended for your station, do not reply until the call is repeated and
When your station is called but the identity of the calling station
is uncertain, you should reply immediately, using the words:
STATION CALLING (your station's identification)
Termination of Communications
To terminate communications, simply conclude your transmission
with the command OUT (which means “conversation is ended and no response is
RECEIVED MESSAGE REGARDING DINNER
Corrections and Repetitions during
When an error has been made in transmission, the word CORRECTION
should be spoken, the last correct word or phrase repeated and the correct version
AT DOCK ALPHA ONE
CORRECTION DOCK ALPHA TWO
Repetitions after Completion
If the receiving operator desires a repetition
of a message, the words SAY AGAIN should be transmitted. If repetition of only a portion of a message is required,
the receiving operator should use the following appropriate phraseology:
SAY AGAIN ALL BEFORE ... (first word satisfactorily
SAY AGAIN ALL BETWEEN ... (last word correctly received prior to the
missing segment) and ... (first word
correctly received after the missing segment).
SAY AGAIN ALL AFTER ... (last word satisfactorily
SAY AGAIN ALL BEFORE “DOCK”
SAY AGAIN ALL BETWEEN “PROCEED” AND
SAY AGAIN ALL AFTER “LOCATION”
Request for repetition of specific items of a message should be
made by speaking the words SAY AGAIN followed by the identification of the message
SAY AGAIN LOCATION
SAY AGAIN TIME
When a station called does not reply to a call
sent three times at intervals of two minutes, the calling station shall cease and not renew the call until after an
interval of three minutes. Before renewing the call, the calling station shall attempt to ascertain that the
station being called is not in communication with another station.
It is sometimes necessary to verify that your transmitter and
receiver are operational. This can be done by:
1. establishing contact on the working
channel and conducting your tests (the actual wording of the test is
given in the example below),
2. not exceeding ten seconds for signal
3. using the readability scale listed below when
giving the report, remembering that a readability of 3 to 5 indicates to the receiving station that it is being copied 100 percent.
1 = Bad (unreadable)
2 = Poor (readable now and then)
3 = Fair (readable with great difficulty)
4 = Good (readable with minor difficulty)
5 = Excellent (perfectly readable)