While you are at sea, a VHF marine radio is your essential connection to the rest of the world. It allows you to communicate with dock workers and other vessels. If there is an emergency, you can use it to send out a distress call. This means that in a worst case scenario, the range of your VHF marine radio can mean the difference between life and death. This is why it is important to augment that range with a powerful antenna.
You shouldn’t buy the first antenna you see. It is important to compare features and options such as length and gain. Below you can view a product table comparing top VHF marine radio antennas in different price ranges.
|Garmin GPSMAP 78sc|
|Garmin Striker 4|
|Garmin GPSMAP 547xs|
|Raymarine Dragonfly 5|
|Garmin Striker 7sv|
|Humminbird Helix 5 SI|
Before you pick the best antenna for your needs, you will need to have a strong understanding of important features. Following are some of the key considerations you should take into account before you make your purchase.
What is a Marine Antenna?
The marine antenna is the contact mechanism between your radio and the outside world. It radiates the transmitter power in order to send the signal in the right direction. A low-quality antenna will misdirect your signals and shorten your range. A high-quality antenna will boost your range and ensure that your signals travel to their intended destination. It will also stand up to all the jostling of your vessel on the high seas and stand the test of time.
Questions to Ask When Shopping for a Marine Antenna
Where will you be using the antenna, and what kind of vessel will you be aboard?
Will you be on a relatively tranquil lake in a large, well-controlled vessel? Or will you be in a sailboat on choppy seas? In rolling waves, you need an antenna with lower dB for a broader pattern of radiation. Go with 3 dB for a sailboat. If you are on a powerboat or calm waters, you can go with 6 or 9 dB gain.
Where will you mount your marine antenna?
There are several common choices. You can ratchet it onto the rail; you can affix it to a vertical or horizontal surface with a flange mount; or you can ratchet it onto a sloping surface. You also have the option of mounting on your mast if you have a sailboat (which you should definitely do). Always mount your antenna as high as possible, and keep it away from other antennas and anything large that’s made of metal. Also make sure it is a minimum of three feet from your marine VHF radio.
What to Look For When Shopping for a Marine Antenna
Shop for a high-quality marine radio antenna which will give you the highest possible range. But bear in mind the following:
In terms of getting the best range, you are going to want to mount your antenna as high as possible. You are stuck with line of sight transmissions, so you can maximize both line of sight and transmission range by mounting high. You might not think this would be an issue at sea, but it is because of the curvature of the earth. You will max out around 35-50 miles. You are in great shape if you have a sailboat, since you can mount the antenna high up on the mast.
If you want to figure out your possible range, use this equation:
Square root of the antenna’s height above water (in feet) x 1.42 = Likely Range in Miles
You need to do this equation for both a transmitting and receiving vessel and add up the results in order to get the predicted range. So if you have a 10-mile range and another boat has a 5-mile range, together you can communicate across 15 miles.
Most antennas are constructed out metal elements inside a fiberglass tube. On the lower end of the price range, you will find a plastic ferrule and low-grade materials used throughout the unit. At the mid-range, you’ll get silver-plated brass elements and crimped connections. Pay top price and you will get a stainless steel ferrule and soldered internal components made out of silver-plated brass. The fiberglass will be of the highest quality and may even include an aircraft-grade finish.
Antennas break regularly. High quality units may last decades; those made out of substandard materials may last only a couple of years.
Also note that higher-quality models may have UV blockers worked into the paint. When cleaning your boat, watch out for harsh chemicals that can strip your finish. Stick with mild soap and water. Wax is okay.
Short high-quality cables
While a high antenna gain can be useful when it comes to boosting your signal, you need to pay attention to the cables you use as well. For every added foot of cable, signal strength is lost. With shorter cables (10-20 feet), that is not a problem, but 100 feet of coaxial cable on a small vessel like a sailboat can cause a loss of up to 80%! Keep cables short when you can; if you need a longer cable, then you should also use the largest diameter you can. Note that this does mean you’ll be adding more weight to your vessel, so you will need to figure out how you can compromise for the best of both worlds.
Separate connector with useful attachment options
Sometimes the connector that comes with a marine antenna is attached, while other times it is separate. It is better to go with a separate connector because this makes it much easier to route your cable. Connection options can vary, but be aware that some antennas require you to solder the connector. So make sure you are equipped to do this if you choose to go with such a product.
Gain (or dB rating)
The gain or dB rating for an antenna is an indication of how it focuses energy. Those with a high rating are able to boost transmitting power through that focus. The downside of a high rating is the diminishing horizontal angle of the signal. Low dB antennas have a broader pattern of radiation, which reduces signal choppiness in rolling waves. This is why a lower dB (3 dB) is recommended for sailboats. Powerboats an use six- or nine-dB gain.
Now you know what features are important to shop for in a marine antenna. Scroll back up to the top of the page to view the features and prices of highly-rated marine antennas!
Garmin GPSMAP 78sc: Perfect for Sailing
Amateur and professional seafarers alike will appreciate Garmin’s 78sc marine chartplotter. Its display is easy to read at any time of the day, plus the depth alarm feature will keep you from running aground.
- Awesome display. Some displays are hard to read in direct sunlight, but the Garmin GPSMAP 78sc’s screen is easy to read no matter what time of day (or night) it is.
- Extended battery life. You can get 30 hours of continuous use or more out of this device, which is more than enough for a full day of sailing.
- Fast performance. The processor is powerful enough to allow you to switch screens with ease.
- Garmin technology. Like most Garmin products, the Garmin GPSMAP 78sc features excellent support and an easy-to-use navigational interface.
- Floats on water. If you drop this device into the ocean, no problem. Just scoop it up and keep on sailing.
- Man overboard button. If someone falls off the boat, hit the man overboard button to mark their position on the map.
- Depth alarms. The depth alarm allows you a chance to avoid running aground when navigating shallow water environments.
- The optional maps for this device are quite nice, but they are also pricey.
- Some people who tried the Garmin GPSMAP 78sc didn’t like the fact that the display is not a touchscreen.
Garmin GPSMAP 547: Split Screen Functionality
The best thing about the GPSMAP 547 is how customizable it is. This device allows you to easily personalize and tweak your display so that the information you think is important is always on hand.
- Plug and play. Setup is super easy and should take most people just a few minutes to complete.
- Split screen functionality. This GPS map’s convenient split screen feature allows you to view extra information as you’re navigating.
- Music app. Garmin Helm allows you to pipe in music through your Garmin GPSMAP 547.
- Excellent quality fishfinder. This device’s built-in fishfinder actually works better than some standalone fishfinder devices.
- Responsive performance. The Garmin GPSMAP 547’s powerful processor allows you to quickly cycle through menus.
- Plot routes from your smartphone. With Garmin Helm, you can plot out a route and upload it the next time you’re close to your Garmin GPSMAP 547.
- Accurate GPS. This device’s GPS system always delivers reliable readings.
- The instructions that come with this product are confusing and hard to read.
- The Garmin GPSMAP 547’s button controls are easy enough to figure out. But if you’re used to touchscreen displays, you might lose patience with it.
Garmin Striker 4: Tough and Affordable
With its thick, heavy-duty shell and rubberized buttons, Garmin’s Striker 4 won’t let you down when the weather gets rough. It’s the perfect navigational device for canoers and small boat fishermen.
- Display looks good in the sun. This device’s bright, detailed display always looks good.
- Affordable. The Striker 4 is cheap compared to most competing marine chartplotters.
- Resists nicks and dings. This product’s reinforced plastic shell is definitely built to last.
- Highly accurate fishfinder. The addition of CHIRP sonar technology is a nice touch.
- Simple navigation. Like most Garmin GPS devices, the Striker 4’s interface is simple and easy to use.
- Very portable. This device’s low profile makes it ideal for ice fishing, canoeing and other marine activities that require you to manage your storage space in a strategic way.
- Comes with everything you need. The Striker 4 comes with a CHIRP (77/200 kHz) transducer, transom and trolling motor mounting hardware and connection cables.
- The Striker 4 doesn’t use “true” GPS maps. You have to enter in waypoints to find your way around.
- This chartplotter was designed to be used in cramped conditions. But if you have plenty of storage space, you may not appreciate the Striker 4’s extra small screen.
Humminbird Helix 5: Helps You Reel In More Fish
If you want to reel in more fish more often, a fish finder like the Humminbird Helix 5 can help you step your game up. Its powerful sonar transmitter, side imaging technology and its bright, backlit display will let you know exactly when and where to drop your line. Another nice thing about this fish finder is that it comes with free mounting hardware.
- Expansion slot. With the Helix 5’s handy microSD card slot, the only limit to the amount of maps you can bring with you is the number of SD cards you own.
- Brilliant display. This GPS unit’s 5 inch, backlit, 800×480 color display is one of its strongest selling points.
- Great for small boats. The Helix 5 works especially well while kayaking or rafting.
- Side imaging. Humminbird’s excellent side imaging technology allows you to know where to go to catch more fish.
- Powerful sonar. The Helix 5’s powerful sonar system enables you to see what’s happening 1,500 feet below the surface of the water.
- Mounting hardware included. This unit comes with a mounting bracket, power cord and a transducer.
- Adjustable filters. Use “max” mode to see everything, or “clear” mode to filter out smaller fish and debris.
- This flexible and customizable marine GPS unit is handicapped by the fact that its built-in maps aren’t very impressive.