books are transmitted by voice radio, the voice
equivalents of the flags are used.
To distinguish numerals from words similarly
pronounced, the proword FIGURES may be used
before such numbers. Numerals are pronounced as
shown in the following examples:
Wun Tree Six
Fife Ze-ro Ze-ro
Wun Fow-er Seven Ait
Wun Six Tou-zand
Ait Wun Too Six Ait Wun
The numeral 0 is always spoken as zero, never oh.
Decimal points are spoken as day-see-mal.
In general, numbers are transmitted digit by digit
except that exact multiples of thousands are spoken as
such. However, there are special cases when the
normal pronunciation is prescribed and this rule does
Prowords are pronounceable words or phases that
have been assigned meaning to expedite message
handling on R/T circuits. Prowords are not to be
substituted for textual words.
The prowords contained in table 4-2 are
authorized for general use. For R/T communication
between units of different nationalities, equivalent
prosigns may be used instead of prowords. When so
used, they are transmitted phonetically.
ACP 125 contains the general procedures for R/T
communication. To become a good operator, you must
follow these procedures and instructions. A few of the
general procedures follow:
Listen before transmitting. An unauthorized
break in transmitting causes confusion and often blocks
a transmission in progress.
Speak clearly and distinctly. Both slurred
syllables and clipped speech are hard to understand. A
widespread error among untrained operators is the
failure to emphasize vowels sufficiently.
Speak slowly. Give the recorder a chance to get
it all down. That way you save time and avoid
Avoid extremes of pitch. A high voice cuts
through the interference best, but is shrill and
unpleasant if too high. A lower pitch is easier on the ear,
but is difficult to understand through background noises
if it is too low.
Be natural. Maintain a normal speaking rhythm.
Group words in a natural manner. Send your message
phrase by phrase instead of word by word.
Use standard pronunciation.
Speak in a moderately strong voice to override
unavoidable background noises and prevent dropout.
Keep correct distance between lips and
microphones. A distance of about 2 inches is correct for
There are many more general procedures that
could make for better transmission. Take time to
become familiar with these procedures.
Dates within the text should be spoken digit by
digit, and the month, in full.
Example: 19 Mar is spoken as one nine March.
Initials used alone or in conjunction with short
titles are to be spoken phonetically.