Navigation Equipment

Choosing Marine Radar for Your Boat, Part II: Selecting the Right Features

Radar display, radar screen, reading radar rings

In Part I of this series, BoatTEST writer Frank Sargeant looked at some of the reasons it makes sense to upgrade your radar to a modern system — or to add radar if you don’t already have it aboard. In Part II, he reviews some of the features you might want to look for when you go shopping for your radar system.

Auto-Tuning Makes Operation Easy

While traditional radar systems used to have to be tuned just about every time you turned them on, modern systems are pretty much touch-and-go, with auto-tuning handling 90% of the adjustments needed in most cases.

multifunction display, split screen, Garmin

Displaying radar on a split screen beside your charting GPS is a quick way to figure out what the radar is showing you. (Garmin)

Your only issue is likely to be interpreting what the screen is showing you, but with today’s sharp color units, that’s much easier. Hotter colors like oranges and reds are usually used to indicate stronger returns, while lighter colors like greens and blues commonly indicate weaker returns. Large solid items like land are bright red, while softer items like a rainstorm or bird flock appear In more muted shades.

And your dealer will set up your radar to operate in an overlay on your chartplotter if you want so you don’t have to try to interpret what those unrelatable rings on screen are telling you.

Smaller, More Efficient and (sometimes) Less Expensive

Raymarine, Quantum 2, marine radar, radome

FLIR - RAYMARINE E70498 M Quantum 2 Q24D Doppler.

So radar can do all this and more for your boating experience. And though radar was once so bulky, power-hungry and costly, it was not practical for small boats. Many modern units are now compact, draw little electricity and are within the budget of many small boat operators.

In general, most modern multifunction displays can operate a radar unit. However, smaller or more basic combos — especially those intended for inland fishing applications — can’t. If you’re considering adding radar to your current equipment, you’ll want to determine compatibility first.

Radar is of course an expected part of the bridge of any yacht or sportfisher these days. And modern systems will usually operate intuitively and seamlessly with all the other electronics linked to current MFD’s within the same family.

There are a few basics to consider, however, when you go shopping for your first radar system.

Open Array vs. Radar Dome

Raymarine, arrays, display, radar

Most radar manufacturers offer open array and radome designs to suit customers from small boaters to those running large yachts internationally. (Raymarine)

Open arrays, with the visible rotating arm, require more space to mount than radomes. They have the narrowest beam width, between 3.5° and 1.1°, the sharpest focus for picking out small targets, and the longest ranges. Open arrays are best for large powerboats with radar arches or pilothouses. They’re also sometimes the choice of smart anglers on smaller boats who look for flocks of birds diving on baitfish—the antenna is usually mounted on a hardtop.

However, radar domes — radomes — with the moving parts inside an 18" (45.72 cm) or 24" (60.96 cm) dome, are usually a better choice for smaller boats. They can be mounted where space is limited and horizontal beam widths between 3.5° and 7° give good resolution on most targets.

For sailors, a radome is safe around halyards and sails because there are no external moving parts to snag in the rigging. They also use less power than open arrays, an important consideration for small boats with limited electrical power, as well as for sailboat operators who hate starting up the generator. And they put out less radiation, making them safer for crew.

Power Output

More power will give you better reception in fog, drizzle or rain. It’s not as important as the height of your antenna, but a 4 kW model can range out to 48 miles (77.25 km) when mounted high enough, while a 2 kW model’s max is 24 miles (38.62 km).

While the 2 kW might be fine for inshore or inland use, the higher power units offer obvious advantages in offshore use—you get what you pay for.

Of course, you don’t often set the unit at maximum range because you’re most concerned about boats within a mile or two of your position, but the extra power also means brighter, sharper returns on smaller targets.

Solid State of Affairs

New solid-state radar units transmit at low power levels. This means minimal power draw and less radiation than with conventional units. Navico’s Broadband 4G Radar emits less radiation than an average cell phone, according to the manufacturer, so it can be mounted in locations that previously were unsafe for crew.

Some of Garmin’s powerful Fantom solid-state open array radars transmit at just 40 to 250 watts, according to the company, compared to 4,000 watts for traditional pulse radar of similar capabilities.

Solid-state systems start up almost immediately, while traditional radar can take up to 3 minutes to appear on your screen. While this might not matter at the dock, it can be huge when you run into a bank of fog while navigating a tricky channel — or when you hear the horn of a ship you can’t see.

B&G radar, B&G radome, radar for sailboats

B&G’s HALO20+ delivers an almost real-time view, with 60 rpm operation at close range for exceptional collision avoidance.

Solid-state radar also provides far better close-range target resolution, even at distances of 1/32 nautical mile, a big plus for those likely to use radar for close-in navigation in a foggy harbor. Targets as small as a single piling or channel marker can be seen on these systems, a huge advantage in pea soup. And there’s no dead zone immediately around the boat, as there often is with pulse radar.

Combination Pulse and Solid State

The latest radar systems are combinations of pulse radar and solid state, giving the best of both worlds in most cases — fast warm-up, minimal power use, excellent resolution and maximum range.

The Simrad Halo series, for example, can reach out up to 48 nautical miles with a 3’ (.91 m) wide array, 64 nm with a 4’ (1.22 m) array and 72 NM with a 6’ (1.83 m) array, according to the company. Halo uses solid-state electronics to produce low-power pulsed frequency-swept transmissions, like the radar equivalent of CHIRP sonar.

Garmin radar, low-profile radome

Garmin’s Fantom Pulse Compression Radar uses “MotionScope” Technology to detect small, fast moving targets. (Garmin)

Fantom™ Pulse Compression Radar

Garmin’s new Fantom™ Pulse Compression Radar, available in 18” (45.72 cm) and 24” (60.96 cm) radome models of 40 and 50 watts, and 4' (1.22 m) and 6' (1.83 m) open array sizes up to 250 watts, is also rated at 72 nm maximum range. The company says the Fantom™ units use the Doppler effect, which Garmin calls MotionScope™ Technology, to detect and highlight moving targets such as small, incoming fast vessels, flocks of birds or weather cells.

What It Costs

Prices range from just over $1,000 for a basic short-range radome unit suitable for small boats to more than $12,000 for a 7’ (2.13 m) open array ready to take you across the world’s oceans.

You’ll also need mounting brackets, which typically cost around $350 for a basic mast mount up to $1,600 for a self-leveling mast mount.

Bottom line is you can probably have radar aboard for a lot less than you might have thought if you’re not running a long range cruiser to distant shores.

Use It Before You Need It

One final word — radar manufacturers note that no radar is effective if it’s never turned on, or if you don’t know what it’s showing you when it is turned on.

Operate your radar when you don’t need it, becoming familiar with operation and imagery in good weather and visibility, so that you’re ready to take full advantage of it when you really need it. Your crew will thank you.

Here are some of the best-known recreational radar manufacturers: