Features March 2005 Issue

Weather Receivers

Garmin's GDL series requires a subscription fee, but offers a wider range of marine weather information than Furuno's Fax 30—and it's in color.

The Garmin GDL 30 (weather receiver) and GDL 30A (weather receiver and satellite radio) overlay a smorgasbord of weather data on a display screen.

For decades, the majority of small boat mariners received weather information near shore through marine VHF radios. Though useful, the information is limited to audio reports on local wind and sea conditions, local marine forecasts, and hurricane, or other severe weather advisories.

On larger vessels, single sideband (SSB) radios are frequently installed, sometimes with a weatherfax printer or PC-based weather program to enhance weather information gathering. The more comprehensive SSB/weatherfax systems are capable of providing long-range reports and graphic displays of weather maps printed directly from the onboard printer.

These capabilities and much more are now available to the small boat owner without the need for a space-robbing SSB radio or its large antenna. Weather receivers that interface with onboard network displays also negate the need for an onboard printer.

Currently, both the Furuno NavNet and Garmin Marine Network have weather receivers that can be added to their respective networks to display various weather data. We tested both.

What We Tested
To interface with the Furuno NavNet system aboard one of our test boats, we temporarily installed the Furuno Fax30 weatherfax receiver and the Fax 5 antenna. We also installed a Furuno-supplied software update to our network displays. The software upgrade was required for our network to communicate with the newly installed Fax30.

The Garmin GDL 30A weather receiver we tested was connected to a full Garmin marine network system that PS used previously for a network system comparison. System features related to this test include the weather receiver, 10-inch and 7-inch multi-function displays, and an XM radio receiver.

How PS Tested
We reviewed each manufacturer’s system using their respective 10-inch network display unit. We based our conclusions and ratings on the weather information provided by each system, how fast it received and updated data, how well the data was presented to the user, and how well the equipment interfaced with both the other network components as well as the user. Initial purchase price, monthly costs, and warranty periods were also considered.

The Furuno black box (actually it's gray) containing the Fax30 measures about 11-3/4" x 8-5/8" x 1-5/8" deep. It has relatively little waterproofing and should be mounted out of the weather. The associated Fax 5 antenna is nearly the same size as an old Loran antenna. Installation requires mounting the Fax30 and the Fax 5 and running cables between the two and the network hub or display.

Our system also required a software update to permit the network components to recognize the Fax30. To execute the update, the tester had to bring a laptop computer to the boat, connect it to the network via a cable, and then update the network's internal software programs by running through a Furuno CD. We found this whole procedure a bit tedious and prone to problems. We had to run the program several times and call Furuno tech support to iron out some minor difficulties.

Furuno spokesman Jeff Kauzlaric pointed out that all NavNet systems built in the last year already include the proper software.

Furuno's weather system uses ground-based radio signals broadcast by the National Weather Service to gather the information displayed in maps and data onscreen. Once connected, the Fax30 can be selected through the display menu on the network screen. Additional weather fax options are soft-key based. As you move from one screen to the next, the soft key labels change to reflect each function.

Three modes of operation are available: NavTex, Fax, and Auto Fax. In the Navtex mode, the unit receives automated text-based data, including navigational and meteorological warnings and forecasts, as well as urgent marine safety information that is broadcast by the NWS on medium frequency (518 kHz). In the Fax mode, once the proper settings are established, the unit will receive and display various maps and charts broadcast by the NWS on several different HF frequencies.

Receiving a map or a chart was slow. Once the proper settings were made to receive a map, we'd leave for 30 minutes to allow complete delivery. Even the manual states that fax images can take as long as 30 to 40 minutes to fully appear onscreen. Kauzlaric addressed the speed issue: "The speed of the actual radiofax broadcast is not controlled by the NavNet system or the Fax30. The broadcast itself is controlled by NOAA or the radiofax system. The Fax30 is better compared to other weatherfax units vs. satellite weather systems. This comparison is a little apples to oranges."

To overcome this drawback and the fact that each map or chart is broadcast at a specific time, the unit can be set to Auto Fax. This allows the Fax30 to receive images as they are broadcast and store them for later review.

We also found the interface between the network and the Fax30 takes a bit of time. Once a weatherfax function was selected, it would take as long as five seconds before the screen changed. We'd often hit the button a second time just to confirm we had actually made a selection, which caused the system to lock up more than once.

We found the Furuno Fax30 and Fax 5 antenna for $1,098. This system has no monthly subscription cost. Furuno warranties the gear for two years on parts and one year on labor.

Bottom Line: A useful weather-gathering tool for sailors traveling more than 200 miles offshore. No monthly subscription fees is a plus.

The Garmin weather system is available as either the GDL 30 or GDL 30A. Only one or the other is needed to complete a network weather system. The 30 is a weather receiver only while the 30A is a weather and satellite radio receiver that provides audio output to a stereo amplifier. Each is packaged with a small GA 31 antenna. Both the GDL 30 and 30A are the same size: 7.3" x 6.7" x 2.2".

To add weather capability, mount the weather receiver black box, wire it for power, and hook up the watertight network cables. Our test system came from Garmin with the GDL 30A and satellite receiver already hooked up and operational so no software updates were needed. New software updates do occasionally appear, offering enhanced features.

According to Garmin senior media specialist Ted Gartner, upgrading the software is easy. "The great thing about the Marine Network is that a user can diagnose all of the Network's components from one MFD (Multi-function Display), load the current configuration onto a data card, electronically submit that information to our website, and get all the latest free software updates loaded back onto that same card. Once that card is loaded back into the unit, the system automatically updates itself."

Garmin uses the XM satellite-based radio system to transmit signals to its weather receiver. Weather information is collected from both government and private weather providers then analyzed and processed by WxWorx, a private weather company that has partnered with XM radio.

This interconnect worked flawlessly; within two minutes of turning on the Garmin network, all the weather data was current. That's astounding speed. Garmin claims its weather system can receive signals throughout the U.S. and up to several hundred miles offshore.

Functions are reached via easy-to-use menus. All specific weather selections are made through menus. The main menu has a Weather tab that leads to three more weather tabs: Current, Forecast, and Sea Surface.

Under the Current tab, we found air temperature, dew point, wind direction/speed, gust, visibility, and air pressure. The information provided was from the nearest airport, in our case the airport in Marathon, FL, about 40 miles southwest. This position can also be user-selected.

The Forecast tab listed a five-day forecast for Miami, as well as a 24-hour forecast for the Marathon area. Under the Sea Surface tab, we found air temperature, dew point, wind, visibility, air pressure, water temperature, wave height, and tides displayed for the nearest sea buoy.

Hit the Map Setup soft key to determine the weather features to display on the map page. This takes you to a menu with a Weather and Sea Surface tab that allows selection of weather features to be displayed on a color overlay on the map page. Under the Weather tab you'll find Nexrad (virtually real-time radar), storm cells, lightning, wind, pressure, hurricanes, visibility, and fronts.

Four items are present on the Sea Surface page: temperature, wave height, period, and direction. To reduce map clutter, each item can be displayed on only selected map ranges or on all ranges. We found weather updates on the Garmin system to be very fast with no user input required.

We found the Garmin GDL 30 available for $599 and the GDL 30A priced at $799. Monthly fees are set up with and paid to XM radio, and they vary from $29.95 to $49.95 depending on the level of service. A $50 startup fee also applies to new accounts. Garmin warranties its weather receivers for one year.

Bottom Line: Garmin'offers fast updates, well-presented color overlay, and a variety of weather information at the hefty cost of a monthly subscription. It's also waterproof, and thus our top pick in network weather systems.

Comparing the speed of data reception between the Garmin and Furuno is like comparing a DSL modem to a dial-up. The Garmin also displays information not available on the Furuno system, including virtually real-time radar, lightning strikes, and storm cell movement. All of this data is displayed in color in a chart overlay. This type of up-to-date, user-friendly, information can be critical to the safety of coastal sailors.

The Garmin system can be used worldwide, while the Furuno Fax30 is limited to several hundred miles offshore. Still, the Garmin GDL 30 is not without its disadvantages, namely, the monthly subscription fees. Only a prospective buyer can decide if the real-time nature of the Garmin weather display and the additional information it provides outweigh those additional costs.


Also With This Article
"Value Guide: Weather Receivers"

• Furuno, 360/834-9300, www.furuno.com
• Garmin, 913/397-8200, www.garmin.com

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