A Marine VHF Radio fixed set generally has the
advantages of a more reliable power source, higher transmit power, a
larger and more effective aerial and a bigger display and buttons. A
portable set (often essentially a waterproof, VHF
walkie-talkie in design) can be carried to a
lifeboat in an emergency, has its own power source and is more
easily water-proofed.
Marine
radios can be "voice-only" or can include "Digital
Selective Calling" (DSC).
Voice-only equipment is the
traditional type, which relies totally on the human voice for calling
and communicating.
Digital Selective Calling equipment, a
part of the
Global Maritime Distress Safety System (GMDSS), provides all the
functionality of voice-only equipment and, additionally, allows several
other features:
- a transmitter can automatically call
a receiver equipped with Digital Selective Calling, using a
telephone-type number known as a
Maritime Mobile Service Identity or MMSI. Such calls take place on
Channel 70.
- a distress button, which
automatically sends a digital distress signal identifying the calling
vessel and the nature of the emergency
- a connection to a
GPS receiver allowing the digital distress message to contain the
distressed vessel's position
The MMSI is a nine digit number
identifying a VHF set or group of sets. The left hand digits of MMSI
indicate the country and type of station.
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More Data and
Information on Marine VHF Radio
* More Data and
Information on DSC for Marine VHF Radio
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Marine
VHF Radio Frequency List - USA and International |
