built in signal converter in addition to the receiver. The
equipment is capable of printing digital facsimile
graphics, HF radioteletype, and CW decoded from
International Morse Code into alphanumeric
characters. Other than tuning the proper radio
frequency and setting the AM/USB/LSB/FM switch, no
additional operator inputs are necessary to print
alphanumeric data, graphics, or imagery.
For use ashore, an optional long-wire antenna or the
whip antenna may be used. The long-wire antenna has
two very long lengths ofreinforced wire extending from
a central connection point. Although this antenna
receives signals very well, it must be lowered from its
installed location and tuned by shortening or
lengthening the two wires for each different frequency
range. Frequency range markings are provided on each
wire. Detailed instructions are provided in an
instruction booklet supplied with each long-wire
antenna.
Q45.
Q46.
Q47.
Q48.
Q49.
Q50.
Q51.
Q52.
REVIEW QUESTIONS
How is the Fleet Environmental Broadcast and
AUTODIN traffic relayed to ships at sea?
Which NAVMETOC regional center is
responsible for the Sixth Fleet Environmental
Broadcast?
What type of data is included in the Fleet
Environmental Broadcast?
Which agency maintains high frequency
regional broadcasts (HFRB)?
What is the purpose of the HF facsimile
broadcastfrom NAVMETOC regional centers?
Which publication contains listings of
frequencies for HF RATT and facsimile
transmissions?
What level of HF frequencies should be copied at
night?
Which type of facsimile recorder is the most
widely used by mobile environmental teams?
SHIPBOARD HF RADIOS
LEARNING OBJECTIVES: Identify the radio
communications equipment routinely found in
shipboard weather offices. Discuss the
applications and use procedures for this
equipment.
Aboard ship, weather observers may be tasked to
operate special radio-receiving equipment to tune in
local HF environmental broadcasts of alphanumeric or
facsimile products. With the advent of TESS (3) and
subsequent advancements in communications
technology, copying an HF radio broadcast with this
equipment is rarely necessary. In this section, we
discuss some basic terms that you must be familiar with,
basic shipboard radio receiving equipment you might
use, and the information systems that are used aboard
ships to receive environmental information.
The equipment you will use to receive I-IF radio
transmissions aboard ship varies for the different types
of broadcasts. Weather personnel are primarily
concerned with receiving voice broadcasts,
Radioteletype (RATT) broadcasts, and facsimile
broadcasts. To receive a radio voice broadcast, all you
need is an antenna, a radio receiver, and a speaker. On
most ships, these are all separate pieces of equipment.
To copy a facsimile broadcast, you will need to patch
the output from the radio receiver into a facsimile
recorder. Finally, to receive a RATT broadcast, you
will need to patch the output from the radio receiver into
a signal converter, then patch the converter output into a
teleprinter. Aboard ship, antenna patch panels and
transfer switchboards are used to connect various pieces
of equipment.
HF ANTENNAS
Aerographers Mates and Marine Corps observers
use antennas both ashore and shipboard to receive HF
radio transmissions of weather information and satellite
broadcasts. Fortunately, many of the meteorological or
oceanographic data reception systems in use have been
simplified so that the antenna that is supplied with the
system matches the frequencies desired. Aboard ship,
antenna usage is controlled by the Radiomen in the
communications spaces. Before attempting to tune in a
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