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The Truth About HF/SSB Radios in an Emergency

Attempting to make a voice distress or urgency call on an HF radio is problematic. 

Ships do not maintain a voice watch.  Very few coast stations maintain a 24/7 voice watch on International distress and calling frequencies.

Furthermore, the correct distress frequency for the time of day and distance to a coast station must be selected on the radio prior to transmission.

Thinking about which frequency to use, and operating the radio correctly at a time of stress is difficult for an experienced radio operator and pretty much impossible for anybody else.

HF DSC Distress Alerts Ships and Coast Stations

By contrast, a DSC capable marine transceiver can send a distress alert by simply pressing the red distress button for 5 seconds.

The radio transmits your vessel position, MMSI, the time in UTC as well as the nature of distress (if selected prior to pressing the distress button).  If the nature of distress is not selected, an undesignated distress alert is sent. 

All ships and coast stations within radio range receive the distress alert containing the above information.

The radio then automatically changes to the correct distress and calling frequency to permit communication with the acknowledging coast station.

A person unfamiliar with the radio can usually manage this, even a child.

When in Distress

Typically when in distress you would activate your EPIRB, then press the red distress button on both VHF and HF radios (if fitted).

The EPIRB alert is sent to the RCC (rescue coordination centre) who will then broadcast a distress relay message seeking vessels able to come to your aid.

With the EPIRB, you have to trust help will arrive.  It will, but the uncertainty from not knowing is challenging. 

On the other hand, if you hear the voice of a coast station operator, or even better a ship's officer saying they are on the way, that can be incredibly reassuring.

All thanks to your DSC capable HF/SSB marine transceiver!

Ship Ahoy!

The HF DSC distress alert will sound alarms on the bridge of ships within radio range.  If a ship is able to assist, they are REQUIRED to contact RCC offering assistance. This happens before they even need to be asked.

This is a feature unique to HF DSC radio and is one of the most compelling reasons to carry a DSC capable HF/SSB radio.  A Satellite Phone cannot do this!

Of course, if there are other recreational vessels fitted with a DSC capable HF/SSB radio and it is switched on, they will also receive your distress alert.

Do the right thing

If you want your HF radio to play any part in emergency communications, it absolutely has to have DSC capability. Spend the money, your life and the lives of your crew could depend upon it.

ICOM's IC-M803, IC-M802 and IC-M801E are all DSC capable.

Some ICOM IC-M802 radios previously sold exclusively in New Zealand have been modified and are NOT DSC capable.  These radios have a metal plate covering the area where the DSC antenna socket is usually located.

Almost every other radio you will encounter, including ALL ham radios are NOT DSC capable. 

Non DSC capable radios are great for other applications, which I will discuss in another blog post, but PLEASE do not rely on them in an emergency.  They are simply not designed for it. 

ICOM IC-M803 HF/SSB marine transceiver

ICOM has launched the IC-M803 HF/SSB marine transceiver in the USA.  This new model replaces the venerable IC-M802 which no longer complies with FCC regulations.

ICOM's NZ distributor advises the IC-M803 is expected to be available in Australia and New Zealand in May / June following the completion of the type approval process.

Some new features:
New color display with night mode (red).
updated DSC Class E with additional monitoring features
Visual match to IC-M605 VHF for those looking to keep a clean look, last call playback voice recording built-in, built-in GPS receiver. Integrated speaker. Waterproof control head and microphone.

The IC-M803 works with the same tuner as the IC-M802 (AT-140), but it does require a different control cable, the OPC1465.

Although ICOM have stopped selling the IC-M802 in the USA, its still shipping internationally and can be purchased from our online store.

 IC-M803 Product Brochure


Listen to HF/SSB radio from anywhere

Have you ever wanted to listen to transmissions between vessels at sea and a maritime coast station?

Well you can!  You just need an internet connected device with a web browser.

Northland Maritime Radio provides software defined radios (SDR's) which can be accessed from anywhere and tuned just like a physical radio with a tuning knob.

We have placed menu items on our web site so you can access a receiver, and have it automatically select one of our working frequencies.

Access is restricted to eight listeners at one time, so try again at another time if it's busy.