Handheld VHF radios are essential pieces of safety gear for sea kayakers. A technology called Digital Selective Calling (DSC) is making handhelds even more indispensible for coordinating groups of paddlers and during emergencies.
The VHFs that sea kayakers have been using are analog transmitters/receivers for voice communications. Those radios now equipped with DSC have an additional digital transmitter/receiver for sending and receiving limited amounts of data such as GPS coordinates. With a DSC-enabled radio, you can press a distress button and a digital help message with your current GPS coordinates is sent to the Coast Guard (and other nearby vessels equipped with DSC radios). Here’s the lowdown on these “rescue me” radios.
Getting a Handle on DSC
DSC has been around for a while and is a popular option in the fixed-mount marine radios used in larger vessels. Within the past several years, DSC has finally started to show up in portable radios—thanks mostly to inexpensive GPS chips.
The Uniden Mystic was the first DSC/GPS handheld and was available circa 2004 at a cost of about $700. It was discontinued because of the high price, some reliability issues and because the Coast Guard’s DSC-based rescue network wasn’t available in a lot of places.
The technology for DSC has improved in recent years, and the cost of the components required has made handheld DSC-equipped radios more reliable and affordable. The two radios reviewed here are the most recent entries on the market and more manufacturers should be jumping on the bandwagon soon.
The United States Coast Guard has created a system called Rescue 21 that’s compatible with DSC radios. The system began being implemented in 2003 and currently covers almost all of the continental U.S. Coast and the Hudson and Columbia Rivers.
Each DSC radio has a unique identification number called an MMSI (Maritime Mobile Service Identity). When a DSC distress message is sent, the MMSI is transmitted to the Coast Guard along with the transmitting radio’s coordinates.
The Coast Guard uses the MMSI to retrieve information about the boat, its owner and emergency contacts from its database of registered MMSI numbers. This allows search and rescue responders to know instantly who’s in trouble and what type of boat to look for. The additional information provided to the database by the radio owner can speed up a rescue.
Registering an MMSI Number
DSC radios don’t come preprogrammed with MMSI numbers; you have to register to get one. The numbers are free and are available online at: www.boatus.com/mmsi/. You fill out a form and when you’re finished you’ll be assigned a nine-digit MMSI number to enter into your DSC radio. The information you provide on the form is added to the Coast Guard’s search-and-rescue database.
If you plan on using your DSC radio on different boats, say your kayak and sailboat, don’t associate an MMSI number with a specific vessel. Instead, in the online form’s Vessel Registration field (which accepts anything you type), enter “Handheld” and in the Remarks field, type “Handheld radio used on multiple vessels.”
Since the remarks can be edited after you get a MMSI number and are immediately updated in the Coast Guard’s database, you can specify which boat you’ll be using before any particular trip.
The BoatUS site is only for United States recreational boaters. If you live outside the U.S., check with your country’s Coast Guard or equivalent to see if DSC is available where you paddle and how to get an MMSI number. Canadians can download a form to register for a free number.
If you’re a U.S. citizen and plan on paddling internationally, it’s a good idea to get an MMSI number issued by the Federal Communications Commission (FCC) instead of BoatUS. U.S. regulations require that a VHF radio to be used in foreign ports have an operator permit.
A cautionary note: When you program a new handheld with your assigned MMSI number, be sure to enter it correctly.
Because of government regulations, once an MMSI is entered in a radio it can’t be changed. If you make a mistake or buy a used radio you’ll have to send it back to the factory so it can be reset.
Using DSC Radios
A DSC radio works just like a standard VHF handheld with a couple of exceptions. In an emergency, open a red plastic tab on the side of the radio (make sure the radio is on). This reveals a red button. Press and hold the button for 3 seconds.
If you have time, you can select the type of emergency from an on-screen list of options. The screen will confirm that the help message with your coordinates has been sent, then automatically switch the radio to Channel 16, where rescuers will try to contact you by voice.
Keep in mind that DSC radios aren’t just for emergencies. They’re also very useful for group paddling trips. MMSI numbers from other DSC radios can be entered and stored in your radio’s address book. Select a name from the address book of someone you want to call; each name has a corresponding MMSI number.
His or her radio will start ringing with an alert tone and automatically switch to the same channel as your radio. You can start chatting. If you and other members of your group are monitoring Channel 16, you don’t have to first hail one another on 16 and then switch to another channel.
You can also request the position coordinates of any radio listed in the address book. The other radio will reply with its latitude and longitude, and its distance and bearing will appear on your screen. The radio can serve as a GPS and set a course to the other DSC-equipped unit.
(DSC doesn’t provide continuous tracking, so if the other radio is moving, you’ll need to make multiple position requests to get the current coordinates. The LHR-80 reviewed here has a mode that will automatically query every 15, 30 or 60 minutes.)
Hands-on with the Standard Horizon HX851 and Lowrance LHR-80
Currently, there are only two handheld DSC radios with built-in GPS on the market; the Standard Horizon HX851 and Lowrance LHR-80. These radios have all the features you’d expect with a handheld VHF radio. They are submersible and include weather channels (plus an alert option for NOAA weather warnings), adjustable volume and squelch controls, channel scan and a Channel 9/16 priority button.
Both are full-size radios; however, thanks to rechargeable lithium batteries, they’re fairly light. The HX851 tipped my scale at 12 ounces while the LHR-80 weighed in at 11.1 ounces. That’s not bad, considering my compact Icom M-88 radio weighs 9.7 ounces.
Like any good marine handheld, both radios are JIS-7/IPX7 rated; they can withstand an immersion in 1 meter of water for 30 minutes. As a bonus they both float. I dunked the radios in a bucket of water for 30 minutes, pulled them out, dried them off and checked for function and leaks.
Both worked normally. The LHR-80 had a small amount of water between the battery and the radio. The battery fits snugly against the radio case, but because there’s no gasket there, a little water got in. The sealed internal electronics are protected, and the battery connection points have small gaskets so some water in the battery compartment isn’t cause for concern. I’d still clean the inside surfaces after exposure to salt water to clean out any salt left after the water evaporates. (Check out the February 2009 SK issue for reviews of other floating and submersible radios.)
Most handheld VHF radios, including the LHR-80, transmit either at low (1 watt) or high (5 watts). The HX851 offers transmission power settings of 1, 2.5, 5 and 6 watts. When you’re sitting low in the water with a small antenna, the more watts the better. And speaking of antennas, I really liked the soft, flexible antenna on the HX851. It’s friendlier than most hard, rigid antennas; especially if you wear a radio mounted high on your PFD.
Both radios come with a built-in, 12-channel GPS chip. Latitude and longitude are displayed and, just as you can with a basic GPS, you can enter and navigate to waypoints—up to 200 with the HX851 and 500 in the LHR-80. Getting a lock on a satellite upon startup was quite fast with both models. Keep in mind that DSC portables only offer rudimentary GPS features; don’t expect color charts, routes, or turn-by-turn driving directions. A DSC radio is not a replacement for your handheld GPS.
One of the main differences between the two radios is the screen. The LHR-80 has a bigger screen compared to the HX851, with larger and bolder text that makes it easier to read. But readability on the HX851 is improved with the backlight turned on. In terms of usability, I preferred the buttons on the HX851. They’re slightly larger, have a better tactile feel, and a more logical layout compared to the LHR-80. Both radios have a number of settings, controlled by on-screen text menus.
Expect roughly seven hours of battery life with the HX851 and eight-plus hours for the LHR-80. The LHR-80 has a higher capacity battery (1400 mAh) compared to the HX851 (1150 mAh). An optional tray for powering the HX851 with 5 AAA batteries is available; essential for extended trips when there are no electrical outlets for recharging. The radios have power-saving settings which can extend use at the expense of turning off the GPS chip.
On the water, both radios had good audio quality while transmitting and receiving. When hailed by another DSC-equipped radio, both the LHR-80 and the HX851 emitted a loud ringing tone guaranteed to get your attention even in the noisiest conditions.
The HX851 has two unique features. A bright LED light is mounted in the radio’s face that can serve as a flashlight or strobe light. If the radio is turned on and is immersed in water, the light will automatically start blinking. Additionally, there’s a glow-in-the-dark band that surrounds the case making the radio easy to find in the dark.
Internet prices for the HX851 generally run between $225 and $270. The LHR-80 is priced from $175 to $200. While both of these radios are more expensive than basic VHF handhelds, the enhanced safety and convenience features of DSC and GPS make either of them well worth considering if you’re thinking about a new radio.