each subscriber requires and slotting the messages into
the appropriate subscriber box.
It is important that the clerk remain alert to prevent
slotting messages into the wrong box. This could cause
an undelivery situation. The distribution clerk, who
handles a great number of messages throughout the
watch, must be aware of high-precedence messages and
ensure that they are reproduced and distributed in a
timely manner for immediate pickup by the subscriber.
The clerk must also be up on the message centers
current SOP for handling special and classified
messages.
To prevent viewing by unauthorized personnel,
certain messages, such as PERSONAL FOR,
AMCROSS, and classified messages, must be placed in
envelopes for pickup by subscribers.
Classified messages are placed in two envelopes;
the inner envelope is stamped with the classification and
any special-handling markings, and then sealed in
accordance with local instructions. The outer envelope
is marked with the addressee, originator, and DTG of
the message, and then sealed.
After reproducing and distributing a message, the
distribution clerk places the original copy into a box for
filing by the file clerk. When a message is reproduced
from the sole copy of a broadcast message, the original
copy or a filler must be returned to the broadcast file.
If two-ply paper is used on the circuit, the top copy may
be used as the master file copy and the bottom copy
retained as the circuit monitor copy.
COMMON MESSAGE ELEMENTS
Before covering the basic format of military
messages, we will first discuss the time system and
precedence categories used in naval communications.
TIME
Time is one of the most important elements in
communications. Messages are normally identified
and filed by either date-time group or Julian date,
depending on the method of transmission.
Date-Time Group
The date-time group (DTG) is assigned for
identification and file purposes only. The DTG consists
of six digits. The first two digits represent the date, the
second two digits represent the hour, and the third two
digits represent the minutes. For example, 221327Z
AUG 96 means the 22nd day of August plus the time in
Greenwich mean time (GMT). The dates from the first
to the ninth of the month are preceded by a zero. We
will talk more about the GMT system shortly.
The DTG designation is followed by a zone suffix
and the month and year. The month is expressed by its
first three letters and the year, by the last two digits of
year of origin; for example, 081050Z AUG 96. The
zone suffix ZULU (Z), for Greenwich mean time, is
used as the universal time for all messages. The
exception is where theater or area commanders
prescribe the use of local time for local tactical
situations. Radiomen never use 2400Z and 0000Z as
the DTG of a message. The correct time would be either
2359Z or 0001Z, as appropriate.
GREENWICH MEAN TIME. In naval
communications, the date-time group is computed from
a common worldwide standard. To meet the need for
worldwide time standardization, the international
Greenwich mean time (GMT) system was developed.
The GMT system uses a 24-hour clock instead of the
two 12-hour cycles used in the normal civilian world.
In the GMT system, the Earth is divided into 24
zones. Zone zero lies between 7 1/2° east and 7 1/2°
west of the 0° meridian. The 0° meridian passes through
Greenwich, England. The time in this zone (zone zero)
is called Greenwich mean time (GMT). The military
more commonly refers to this as ZULU time. Both
names refer to the same standard.
Each time zone extends through 15° of longitude.
Zones located east of zone zero are numbered 1 through
12 and are designated minus. To obtain Greenwich
mean time, you must subtract the zone number in
which you are located from local time.
Zones located west of zone zero are also numbered
1 through 12 but are designated plus. These zones must
be added to the local zone time to obtain GMT. As we
will discuss shortly, the 12th zone is divided by the
180th meridian, which is the international date line.
Each zone is further designated by a letter. Letters
A through M (J is omitted) designate the eastern, or
minus, zones. Letters N through Y designate the
western, or plus, zones. The designating letter for GMT
is Z (ZULU). The zone number, prefixed by a plus or
minus sign, constitutes the zone description. Zones
crossing land areas often follow boundaries, natural
features, or regional demarcations to keep similar or
closely related areas within the same zone.
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