If you’re going out on a boat, you absolutely need some way to communicate with others. Sure, we’ve come a long way from using semaphore and flags to talk to other ships, but you need more advanced comm gear than just the smartphones of the crew members and passengers.
Basic Types of Marine Communication Equipment
In general, there are 3 types of marine radio communication equipment, with transceivers that can both transmit and receive radio signals.
VHF: This is for short-range communications up to 50 kilometers. In general, VHF equipment doesn’t cost a lot, and they’re much easier to use. VHF marine radios are perfect for the cruise ships. You only have 3 controls:
- This control uses simple channel numbers to pick the frequency for transmitting and receiving radio signals. You may also have controls to scan for a variety of signals, or to immediate set to the distress channel.
- This control sets the audio volume level for the signals you receive.
- This sets the squelch level, which works to quiet the background noise when you’re not currently getting any signal.
- This stands for digital selective calling, which enables you to quickly send an alert (already automatically formatted) to rescue groups such as the Coast Guard.
HH-SSB: This type of system is more expensive and more complicated. However, its range can reach up to 5,000 kilometers. This type also has the ability to select the distress and calling frequency in the MF radio band.
Some HH-SSB systems can receive weather fax messages from around the world, so you may be able to get a more complete idea of the weather in a particular region. You’ll need additional hardware, such as:
- Radio modem
- Text decoder
There are also some systems that allow for Internet communications, or more specifically sending and getting email messages. Because of the limited audio bandwidth, you’re generally limited to text email messages without attachments. You’ll need:
- Radio modem
- PC-based software coder-decoder
Satellite: The Global Maritime Distress and Safety System (GMDSS) uses geo-stationary INMARSAT satellites in space for worldwide communications. You have 2 different standards:
- INMARSAT-B. This is for using the telephone for direct calls, and for data and telex communications. The main problem here is that this standard needs a huge directional satellite antenna, and it has to be aligned continuously to the communications satellite. That means it’s not exactly practical for small boats with private owners.
- INMARSAT-C. This is for telex communication. This only needs a very basic omni-directional antenna. While this doesn’t enable any voice communications, your telex communication can have a worldwide reach.
You will generally need the following components.
- Small satellite transceiver
- PC-based telex station with a monitor and keyboard. This lets you print and write text-based telex messages. Nowadays, you may be able to use this system for email messages.
Required Radio Communications for A1 to A4
The GMDSS has set the world into 4 distinct areas, and these have been designated as A1, A2, A3, and A4. These areas of operations will require specific sets of marine communication systems.
A1: This area is about 20 to 30 nautical miles from the coast. It has to be under the coverage of at least one VHF coast radio station with available continuous DSC alerting. If your boat has an A1 area of operations, you’ll need:
- A VHF transceiver
- DSC capability
- A NAVTEX receiver. This is for navigational telex communications so you can get maritime and weather information.
A2: Theoretically, this extends up to 400 miles offshore. But normally, the A2 area of operations covers 100 miles off-shore and doesn’t cover the A1 areas. For A2, you will need:
- Radio telephone with MF radio range
- All the other equipment required for A1 area of operations. That means you still need the VHF transceiver and the NAVTEX receiver.
A3: This area of operations is outside the A1 and A2 areas. In addition, the A3 area of operations is within 70 degrees north and 70 degrees south latitude. It is also within the range of INMARSAT geostationary satellite coverage, so you still get continuous alerting.
For A3, you will need:
- High frequency radio
- INMARSAT radio (though this can be an alternative instead of an addition to the high frequency radio)
- System that receives Maritime Safety Information (MSI)
- A1 and A2 marine communication equipment
A4: This is the area outside the A1, A2, and A3 areas, and we’re basically left with the polar regions beyond the 70 degrees north and south of latitude. If you’re going to the Arctic Ocean for some reason, you’ll need the following gear:
- High frequency radio service
- A1, A2, and A3 marine communication equipment
Nowadays, virtually every ship carries the satellite terminal for Ship Security Alerts System (SSAS). This is also for long range identification and tracking as set forth by the SOLAS requirements.
Because of radio technology, ships today are much safer since they can immediately ask for aid when they get in trouble. Ships today are more efficient when it comes to communicating with other ships and with stations on shore.
In fact, radio communications have become so advanced that you don’t need a skilled crew member to act as your dedicated, 24/7 radio officer constantly keeping watch.
With radio, you can also get a good idea of the weather conditions of the waters you’re entering. You can be better prepared, and maybe even avoid waters with terrible weather. That means you can avoid getting into trouble in the first place, which beats being able to ask for help when you do get in trouble at sea.
The good news is that even if you’re involved in an emergency situation, you can ask for help from other boats and rescue services—with the proper marine communication equipment.