Icom UK Blog

A Simple Guide to Marine Radio – Part 1 October 27, 2011

This guide goes someway to explain suitable radio products used to communicate at sea.  It is not intended to replace guidance from professional radio specialists such as RYA appointed instructors.  This is general information about the different types of marine radio products available and will hopefully help you make an informed choice when purchasing.

What is VHF?

The most popular way of communicating at sea is via a marine VHF (Very High Frequency) set. These are combined transmitter/receivers that operate on allocated frequencies known as ‘channels’.

Marine VHF radios are used for a variety of purposes including; contacting harbours, marinas, locks, summoning the rescue services and ship-to-shore or ship-to-ship communication. To prevent maritime transmissions creating interference with other radio users, a section of the radio spectrum has been allocated specifically for marine communications.

To make operation within the spectrum as simple as possible, radio frequencies have been organised into numbered channels (eg. Ch.16 actually refers to156.800MHz). The VHF marine radio band remains consistent around the world, ensuring that vessels travelling on international voyages can always communicate. There are 55 international marine channels, a similar number of private channels (allocated on a local basis to commercial organisations), and some unique national channels. Channel 16 (156.800MHz) is the international calling and distress channel.

Handheld Marine VHF Radio

Handheld Marine VHF radios work in exactly the same way as their fixed equivalents. Many of the features are shared and in ICOM’s range they even follow the same operating protocol, to help users who use both types. As with any tool there are advantages and disadvantages.

Handheld advantages include small size and portability, usefulness in an emergency, should a vessels electrical power fail, independence from the vessel’s power and antenna, and value. Disadvantages are related to the power output and battery life, which affects range and how long the handheld can be used.

To summarise, compact size makes handhelds more suitable for small vessels without their own battery source; or as emergency back-up for fixed radios or as additional radios for crew and use in tenders etc.

Fixed or panel-mount Marine VHF radio

All ICOM fixed-mount marine VHF radios have DSC calling capability, allowing you to alert other boats, ships and shore stations with the single press of a button.These DSC capabilities include; position polling, a variety of group calling options and the ability to connect to a remote microphone and act as an inter-ship intercom system. Many radios also have automated fog horns that connect to an external hailer horn to act as a public address system and built-in hailers .

Fixed radios do require installation, including connection to a power source, VHF antenna and GPS antenna. When siting your radio, you should think about how it will be used. You will probably need it whilst navigating and at the helm when entering or leaving port. Think carefully before installing.