Broadcasting The Sea: How Marine Radio Connects Us To The Deep

You may not know it, but if you’ve ever been out on the water, you’ve heard about one of the most intricate communication systems in the world. Sailors have used marine radio for decades to keep ships safe and connected to each other and broadcast weather information and other important announcements to boaters out at sea. With this capability comes responsibility. However, marine radio operators must take continuing education classes to keep their licenses updated.

A marine radio isn’t just something that marine professionals use; anyone with a boat should consider having one to keep themselves safe on the water. Whether in an emergency or communicating with other vessels, having your marine radio is crucial and can save your life in many situations.

But what is a marine radio? How do they work? And what can they do for you? This article will take you through what exactly a marine radio is, how they work, why they are essential, and more to help you decide if one could be right for you.

Overview of a Marine Radio

A marine radio is a communication equipment on board your boat or ship, and it’s required by the United States Coast Guard (USCG). However, many boaters are unaware of precisely what these radios do and why they’re essential.

Broadcasting The Sea How Marine Radio Connects Us To The Deep

A marine radio is essential safety equipment for any boat owner or operator. Marine radios let you to communicate with other boats in your vicinity and with any nearby coast guard or emergency services. In an emergency, a marine radio can be used to call for help or alert other boats to your situation.

It is the main form of communication on coastal seas and has several advantages over a mobile phone, a CB radio, or other forms of communication. Most VHF marine radios also provide 24-hour access to NOAA weather forecasts.

The History of Marine Radio dates back to the 1920s. In 1929, the American Telephone and Telegraph Company (AT&T) introduced the first marine radios to American ships. These radios were designed for commercial shipping that traveled between the United States and Europe. From 1935 to 1945, these radios were used for defense during World War II.

The war ended in 1945, but it was not until 1949 that two-way radiotelephone communications on maritime vessels were authorized by international agreement.

A marine radio can also be used for non-emergency purposes, such as checking the weather forecast or contacting a tow company. Having a marine radio on board can help make your time on the water more enjoyable and safe.

Marine radios use the VHF (Very High Frequency) band, which ranges from 156.000 MHz to 162.025 MHz. In other words, marine radios operate on frequencies that are much higher than those used by AM or FM radio stations.

Related: Radio Station Gameplan: What radio station is the mariners game on today

Four general bands or ranges can be used to categorize the frequencies utilized for these systems in the United States: low-band VHF (49-108 MHz), high-band VHF (169-216 MHz), low-band UHF (450-806 MHz), and high-band UHF (900-952 MHz). VHF and UHF stand for “Very High Frequency” and “Ultra High Frequency,” respectively.

The maximum range of the 27 MHz radio, which usually ranges between 8 and 16 kilometers, is seen as more of a coastal radio. With a maximum range of up to 20 kilometers between vessels or up to 50 kilometers from a shore base, VHF radios are clearer and more powerful. They are frequently utilized for offshore as well as coastal applications.

The advantage of using these high-frequency bands is that they can transmit over longer distances, through obstacles like hills and buildings, and can even be picked up in satellite dishes. The transmitter will require a 12-volt power supply with at least 1 amp output, while the receiver requires only 3 volts DC.

Marine Radio Communication, Bandwidth, and Regulations

All maritime safety professionals should take communication very seriously. It is essential to stay in contact when out on open water, away from shore. That’s why so many sailors rely on the trusted use of marine radios.

There are two types of marine radios available for boaters, depending on their needs: VHF (Very High Frequency) or SSB (Single Side Band). The frequency range for VHF is between 156-162 MHz, and the range for SSB spans 2-29.9999 MHz. Whatever you choose will depend on your needs, but they both have benefits worth considering.

Just like your cell phone has a designated frequency, so does your marine radio. In the United States, the FCC regulates these frequencies. Most marine radios operate on one of three marine radio bands: low frequencies (LF), very high frequencies (VHF), or ultra-high frequencies (UHF). Here’s how they break down:

LF operates in the 3 to 30 kHz range, VHF ranges from 30 to 300 kHz, and UHF operates in the 300 kHz to 3 MHz range. Marine radio bandwidth and frequency bands are both essential when it comes to your communications equipment. If you are operating on the wrong bandwidth, you may not be able to transmit or receive.

If you have the wrong frequency, you may be transmitting into an occupied channel that will not allow for communication. With so many frequencies to choose from in marine radios, it can be difficult to know which one to use.

If you’re new to marine radio, talking on one can be daunting. But it’s quite simple, and once you get the hang of it, you’ll be able to communicate with other boaters easily. Here’s a quick guide on how to talk on a marine radio.

  1. Before talking, ensure you’re on the right channel. There are usually three channels in use – Channel 16 is for emergencies only, Channel 12 is for boat-to-boat contact, and Channel 6 is for bridge-to-bridge communication.
  2. When you want to speak, wait until someone else stops talking before expressing yourself.
  3. When you want to respond or ask a question while someone else is speaking, wait until they finish their sentence before saying anything – this will help avoid confusion.
  4. Never interrupt another speaker unless there’s an emergency. Just wait for them to finish speaking first.
  5. Speak slowly, clearly, and distinctly when talking on a marine radio.
  6. Be mindful of any background noise when speaking on a marine radio. Background noise could confuse others and make it hard for them to understand what you’re trying to say.

Types of Marine Radios

There are many types of marine radios, each with features and benefits. For example, handheld marine radios are great for boaters who want a compact, lightweight option that can be easily stowed away. An installation-free radio would be perfect for any boat owner looking to save on installation costs and keep the boat clean. Those looking to go even more minimalist might opt for a solar-powered radio to ensure they never have to worry about power again.

1. Handheld VHF Marine Radio –

A handheld VHF marine radio is a portable, easy-to-use communication device essential for boaters. VHF radios allow you to communicate with other boats, the Coast Guard, and other emergency services in the event of an emergency.

The most popular type of radio on boats, these portable devices allow boaters to communicate over large distances without breaking a sweat.  

Handheld VHF Marine Radio

2. HF/SSB (Long Range) Marine Radio –

These radios use frequencies up to 30 MHz, so you’ll get a greater range than your typical VHF or shortwave device.

Similar to your VHF, the Marine MF/HF-SSB radio has a transmitter and receiver. The frequency bands in which they operate are the main distinction between them. Marine MF/HF-SSB radios typically operate between 1.6 MHz and 30 MHz frequencies.

Thanks to ionospheric refraction, HF radios can transmit over much longer distances. Still, the signals might be distorted by atmospheric phenomena like geomagnetic storms or solar flares that radio users have no control over.

HF/SSB (Long Range) Marine Radio

3. Fixed VHF Marine Radio –

While a fixed VHF is permanently attached to your boat, it functions the same as a handheld VHF. The radio itself and an antenna for signal broadcasting are two independent components. It is a larger radio that will require space in your boat and a power source to be fitted.

As the name suggests, fixed VHF radios stay in one place and come with everything needed for an installation. They’re typically mounted near the helm or other central locations so all occupants can use them at once.

Fixed VHF Marine Radio

Important Features of a Marine Radio

A marine radio is an essential equipment for any boat, large or small. Marine radios allow you to communicate with other boats in your vicinity and with the Coast Guard or other emergency services if necessary.

  • Channel Selector –  The channel selector lets you select which channel (1-22) you want to talk on. This will either be a rotary knob or a pair of buttons marked up and down. For a rotary knob, turn it clockwise to go higher and counterclockwise to go lower. For buttons, press one button at a time to scroll through each channel.
  • Power Selection – All VHF radios have high and low power options. Low power is typically used when communicating over short distances, while high power should be used when communicating over long distances.
  • Squelch Control This is used to clear weak background signals that come across as interference. Adjusting this control will raise or lower the squelch level. There are also some radios where this setting can be adjusted digitally using a set of switches instead of a dial.
  • Scan – By pressing the scan button, the radio will scan all channels (or the ones you have preset). The radio will pause on that channel when it detects a transmission so the user may listen. Press the scan button again to stop scanning.
  • Dual Watch – This allows you to switch between two channels. On most dual watch systems, pressing the Dual button once selects channel 1 only; Pressing it twice selects both channels 1 and 2; Pressing it three times selects both channels 1, 2, and 3.
  • End or Clear – This button’s primary function is to cancel DSC alerts. However, its secondary function is to end transmissions. To end a conversation, hold the button down until you see End appear on the screen.


A marine radio is an essential piece of equipment for any boat, whether you’re fishing off the coast or sailing around the world. In short, a marine radio is a two-way radio that uses VHF frequencies to communicate with other boats and ships and with shore-based stations. Marine radios are vital for safety at sea, as they allow you to call for help in an emergency.

The most common type of emergency is when your boat runs out of fuel, and you must get towed back to shore. These days, most people carry their phones instead of having a dedicated marine radio on board, but it’s much safer than depending on cell coverage alone.



How far can a marine radio transmit?

The most significant distance between aerials mounted on tall ships and hills is around 60 nautical miles (111 km). The maximum distance between aerials mounted on small boats at sea level is 5 nautical miles (9 km; 6 mi). Transmission power ranges between 1 and 25 watts.

Why do you need a radio on a boat?

Marine Radio on a boat can be used for voice communications and non-voice communications. It can be used to communicate with other boats, the coast guard, or anyone else in your vicinity.

How Many Amps Does A Marine Radio Draw?

The majority of radios use 10 amp fuses. Based on a typical Horizon Eclipse VHF, this is from the west marines website. It appears to use a maximum of 6 amps for transmission but only 1.5 amps for a reception.

How to connect Bluetooth to boss marine radio?

Turn on BT mode on your phone before starting the pairing process. The “BOSS MR632UAB” will be displayed when the phone is connected to the car audio system. Select the “BOSS MR632UAB” from the device list to pair with and connect to the vehicle’s audio system. When you see the BT logo, the process will end.

How to do a marine radio check?

Check the radio’s power connections with the power distribution panel for tight, sturdy, and corrosion-free connections.

Set the radio to one-watt power and press the microphone button. Call “radio check” three times, then give the name and position of your boat.

How to register a VHF marine radio?

A marine VHF radio requires a ship’s radio license once installed in a vessel. You can get this on the OFCOM (Office of Communications) website.


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