How To Use A VHF Marine Radio? (All You Need To Know)


I have been boating for many years but mainly inlet or in lakes. When I decided to cross the gulf stream and take my boat to the Bahamas, the need for a VHF radio became obvious. So I went ahead and did a lot of research on how to properly use a VHF radio and want to share with you what I learned.

There are probably thousands of different brands and model VHF radios. For the most part, the main features seem to be pretty standard across brands.

  • Adjust squelch– when you turn on a new VHF radio its very likely that you hear nothing but static. Adjust the squelch setting accordingly until the static is gone. This will allow you to turn the volume up and listen to people instead of static.
  • Adjust band– Most VHF radios sold in the US are capable of transmitting and receiving over multiple bands. Unless you have a specific reason, you should select USA frequency. 
  • Channel 16– this channel is monitored internationally for distress signals. If having a privet conversation on another channel, make sure to toggle back between that channel and 16.
  • Speak– Press and hold the PTT button (press to talk) and speak as clear as possible into the microphone. When finish talking, release the PTT button. Be careful not to cover the microphone with your hand when speaking on the radio.

In addition to the steps above, here are some additional tips and best practices followed among fellow boaters.

1- Channel 16 is for emergency and hailing only (you should always monitor this channel)

2- There are 4 marine communication categories

  1. MAYDAY – (pronounced “MAY-DAY”): This a distress signal and should only be used on immediate danger or emergency and requires immediate assistance.
  2. PAN-PAN – (pronounced “PAHN-PAHN”): This is the international standard urgency signal used to declare that there is a situation that is urgent, but for the time being, it does not pose an immediate danger to anyone’s life or to the vessel itself.             
  3. SECURITE – (pronounced “SAY-CURE-A-TAY”): This is the safety signal and is used to advise others about important navigation or weather warnings that may impact the safety of other vessels.
  4. ROUTINE– Not safety-related communication between boaters

3- To report an immediate danger emergency (Mayday Call)

  • Set the channel to 16
  • Speak as clear as you can and say Mayday, Mayday, Mayday.
  • Say the name of the vessel three times (this the Santa Maria)
  • Say Mayday and vessel name once more
  • Provide your location (GPS coordinates, magnetic bearing or an approximated distance and direction from another vessel or landmark)
  • Give a description of your boat including boat type, color, length, and any other distinctive feature.
  • Say the nature of your distress call. Is the boat sinking? Are you or a crew member injured? Is there a fire on the boat?
  • Inform them of how many passengers are on board ( two adults and 1 child onboard)

 4- To report an urgency (Pan-Pan Call)

  • Set the channel to 16
  • Speak as clear as you can and say Pan-Pan, Pan-Pan, Pan-Pan.
  • Say the name of the vessel three times (this the Santa Maria)
  • Provide your location (GPS coordinates, magnetic bearing or an approximated distance and direction from another vessel or landmark)
  • Give a description of your boat including boat type, color, length, and any other distinctive feature.
  • Say the nature of your urgency call. A small fire on the boat? Is a crew member injured?
  • Inform them of how many passengers are on board ( two adults and 1 child onboard)

5- To talk to another vessel

  • Set the channel to 16 and monitor for at least 30 seconds to make sure you ate not interrupting other important calls.
  • Say the name of the vessel you are trying to reach three times
  • Say your vessel name
  • Wait two minutes before repeating your call and fifteen minutes after three tries.
  • When the other vessel responds, ask them to move to another channel.
  • The recreational channels are 68, 69, 71, 72, 78.

6- Here is a table with all the channels and what they are for.

VHF Marine Channel NumberAuthorized Use Of Channel
16International Distress, Safety and Hailing.
09Alternate Hailing Channel.
13Intership Navigation, Draw bridges & locks.
68, 69, 71, 72, 78ANon-Commercial Recreational
06Intership Safety
17, 21A, 22A, 23A, 81A, 82A, 83AState and Federal Government only
07A, 08, 18A, 19A, 67* 79A, 80A, 88A*Commercial
* Intership Only
01A, 05A, 10, 11, 12, 14, 20, 20A, 63A, 65A, 66A, 73, 74, 77Port Operations, Commercial and/or VTS.
24, 25, 26, 27, 28, 84, 85, 86Public Correspondence (Marine Operator)
15Receive only. Used by Class C EPIRBs.
70Digital Selective Calling 


Getting Rid Of The Static

After installing a VHF radio on your boat and turning it on for the first time. You would immediately notice the static sound on the radio. This static noise is called “squelch”. To get read of the squelch so you can actually listen to wats been transmitted over the radio, you must find the squelch setting on your radio and adjust accordingly until you would no longer hear the static sound. Then, tune in to the most important channel when you’re underway. Here is a video demonstrating how to do it.

What Is The Most Important Channel On A VHF Radio?

Channel 16 is the most important. This is the one that is being monitored by the US Coast Guard. This is where you must send out distress calls in times of emergency. Other boaters also tune in to this channel, so you will hear emergency calls from other areas as well. Usually, if boaters are near the emergency, they assist the distressed vessel.

By monitoring Channel 16, you would also be able to hear transmissions from the Coast Guard. Any important update on the weather condition or anything related to the seas and your vessel will be transmitted by the Coast Guard through this channel. So aside from the emergency calls that you would be able to monitor, you will also receive important updates from the Coast Guard through Channel 16.

How Do You Know Your VHF Radio Is Functioning Correctly?

To ensure that you have a fully-functional VHF marine radio while underway, you need to perform a routine radio check. Make sure that you do not use Channel 16 for this process. You wouldn’t want to hog the line and prevent important transmissions like legitimate emergency calls or Coast Guard updates.

You can use the available open channels, which are 68, 69, 71, 72 and 78A. These channels are used for conversations so you can freely “talk” over this channel. Next, turn your radio to the 1-watt power setting.

To confirm whether someone will be able to hear your transmissions, use the communication convention in this manner: 3 “radio check,” then your “boat name,” and lastly your “location.” Say, for example, your boat name is “Aqua Seafarer”, and you’re located at South Harbor Marina, your routine check would sound like this, “Radio check, radio check, radio check, this is Aqua Seafarer in South Harbor Marina.” Then just wait for a confirmation that somebody has heard your transmission. When someone has confirmed, you will know that your VHF marine radio is working.

Discover Boating

It would be best to do this routine performance check before you pull out of the harbor. Don’t risk going out to sea with a defective or poorly performing radio. You’ll never know what conditions you would be facing. As the adage goes, it is better to be safe than sorry.

Can You Communicate Other Non-boating Related Matters Over The Channels?

Technically, you can. However, it is unethical to talk about a baseball game or your kids on open channels. While you may not be tuned in to Channel 16, you might still want to minimize chitchats over these channels as a lot of people are also tuned in to them. Sometimes, there may be important, albeit, non-life-threatening information that needs to be transmitted to someone, but it may not be possible because you are talking about a basketball game with your buddy.

How Can You Reach A Buddy Who Is In Another Location?

Proper convention on marine radio use would be for you to call out your buddy through Channel 16. Once your buddy and he has responded, you will then invite him to another channel to free up channel 16.

Usually, you can do this by calling out your buddy’s boat name three times, then you will mention your boat’s name and end it with “over.” For instance, if your buddy’s boat name is “Rover One,” and your boat’s name is “Big Momma,” then you would be making the transmission this way, “Rover One, Rover One, Rover One. Big Momma. Over.”

Once your buddy has heard it, he would reply this way: “Big Momma, this is Rover One. Over.” Next, you respond to it with the channel that you would like to transfer to. For instance, you can say, “72.” You and your buddy would then move to this channel.

There may be times that your buddy wouldn’t immediately hear you. The basic rule is for you to wait for 2 minutes, at the very least, before calling him out again. After the 3rd attempt and you still have not heard from the other party, you now need to wait for 15 minutes before calling out again over channel 16. Remember that this channel is mainly used for emergencies and for monitoring Coast Guard’s transmissions. You wouldn’t want to render the channel unusable for other vital communications.

What Are The Types Of VHF Marine Radio?

There are two kinds of VHF marine radio.

Fixed-mount VHF radio- This type of radio is permanently installed on your boat and connected to an external antenna. It derives its power from the boat’s battery, so your operating time is practically unlimited. All fixed-mount radios are limited to 25 watts of transmitting power bay law. They also have the capability to transmit at 1 watt, which you should do when talking with nearby boats. This way, you will interfere with fewer vessels. This radios will also have a longer range, here is why.

The difference in range between a 25-watt fixed marine VHF radio and a 5-watt handheld is due to the fixed mount’s antenna being taller, and therefore it can “see” farther. More power will allow you to punch through static and other radio traffic better, but only within the range dictated by antenna height. Marine VHF radios work on a line-of-sight basis. That is, they can transmit and receive to and from another antenna as long as that antenna is above the horizon. How far is that? Standing in the cockpit of a boat, the distance to the horizon for most adults is about three miles.

Boating Mag

Handheld VHF marine radio- This radio might look similar to a walky-talky but make no mistake, it is a very capable radio. Most handheld radios have all the same features as the fixed mount radios. The main difference between the two (besides being portable) is transmitting power. Because these radios are battery-powered, the transmitting power is usually limited to 3-6 watts.

Handheld radios can be your primary radio if you do all of your boating near shore. It can be an awsome back if you have a fixed mount installed on your boat. In case of an emergency, If for some reason the boat’s electrical system is down, you may still be able to use this type of radio to send out distress calls. Most handheld types are also waterproof and rugged, I keep two on my boat and use them to communicate with my crew when we go exploring on islands like The Bahamas.

What Is MMSI

MMSI Overview Maritime Mobile Service Identities (MMSIs) are nine digit numbers used by maritime digital selective calling (DSC), automatic identification systems (AIS) and certain other equipment to uniquely identify a ship or a coast radio station. MMSIs are regulated and managed internationally by the International Telecommunications Union in Geneva, Switzerland, just as radio call signs are regulated. The MMSI format and use is documented in Article 19 of the ITU Radio Regulations and ITU-R Recommendation M.585-6, available from the ITU.

USCG

VHF Radio With Or Without Internal GPS

You definitely want a VHF radio with a GPS integrated. For once the price is similar to the non-GPS units and in case of an emergency, you will be glad you have it. This is because the DSC feature (Digital selective calling) will send a more accurate location of your boat to the U.S. Coast Guard.

When connected to a Global Positioning System (GPS) the radio will transmit the caller’s position and type of distress and display it as an icon on the chart plotters of boats that receive the call. The system then determines the distance and heading to the distressed vessel, thus allowing nearby boaters to assist in cases where they are closer than the U.S. Coast Guard (please follow the instructions of the U.S. Coast Guard in all emergency situations.). Additionally, MMSI numbers allow boaters to connect directly to other boaters and marine assistance dispatchers with DSC-VHF radios, which will decrease the amount of traffic on commonly used radio channels.

Seatow

Final Thoughts

A VHF marine radio is a very important tool on any boat and especially if you plan on taking it offshore. Having one on board and knowing how to use it could mean saving your life and that of your passengers. You need to know some of the most important details in operating a VHF radio while you’re underway. Essential knowledge on the channel, routine performance checks, the kind of language, as well as the regulations surrounding the use of this radio, can make your boating trip enjoyable and more secure.

These are the radios I have on my boat in case you want to check them out. I have been using them for about three years and have no complaints so far.

Alejandro Cruz

I’m part of a family of "aquaholics" We love everything about the boating lifestyle. From fishing to exploring new waters to everything in between. We love going on new adventures as well as just chilling in the water. In this website, we want to share with you everything we have and continue to learn about the boating life 365!!

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