Open main menu

Outdoor Retailer: Personal locator beacons in the backcountry

Currently, there are two main locators available to the backcountry traveler: the ACR 406 series and various SPOT devices. While ACR and SPOT share some capabilities (like new, non-emergency messaging functions), the ACR and SPOT units operate under significantly different paradigms, as discussed in my SPOT gear test article.


ACR's 406MHz personal locator beacons (PLB's) use the COSPAS-SARSAT satellite system. In their current SARLink and AQUALink forms an emergency activation transmits the user's GPS-derived location through the GEOSAR (geosynchronous) and LEOSAR (low orbit) satellites.

True PLBs, like the ACR,  transmit on two frequencies, 406MHz (for the satellites) and the old standby 121.5MHz for homing (the standard frequency for aircraft ELTs, for example). The 121.5 frequency can be used with Doppler location in case of failure of the unit to transmit a GPS-derived position.

ACR claims "true global coverage" for the system, though strictly speaking, this is incorrect. The regions in the immediate vicinity of the North and South Poles are only marginally covered. However, all continents and ocean regions are covered, subject to the usual limitations imposed by canyon and canopy.

Like SPOT (below), the new ACR units have added limited non-emergency messaging capability. ACR's 406Link service allows you to self test your unit to confirm it is working and send pre-programmed messages to a designated group of five contacts. Unlike SPOT, messages are sent via the COSPAS-SARSAT satellites. The 406Link service costs $39.99 annually for Basic service (self testing messages to the account owner only) or $59.99 for Plus service (self testing plus "I'm okay" pre-programmed messages sent to five contacts via text and/or e-mail).

ACR also added digital displays to two units: the SARLink View and the AquaLink View (the more buoyant marine version, in case you drop it out of your kayak mid-ocean). In an emergency, they display data, like GPS coordinates and remaining battery power, so you know the beacon is working to summon help. When sending non-emergency messages, the View units include your GPS-derived location with a link to view the location on GoogleEarth. With SARLink and AquaLink only the pre-programmed message is sent.



SPOT has two new packages. The first is the SPOT 2 Satellite Messenger, which launched last fall. The new unit is smaller than the original by about one-third and has a higher sensitivity GPS chipset. This higher sensitivity is said to overcome many of the deficiencies due to the old chipset and antenna design when under canopy (canyon effects require a different approach that is not found in civilian GPS receivers).

The SPOT 2 retains the "911/Rescue," "OK," and basic "Help" messages, plus some added user-selectable messages. The "Help" and "911" buttons now have removable covers added to reduce accidental transmissions. SPOT uses the GlobalStar satellite phone system to transmit its location and various messages. The use of the digital service on the GlobalStar satellites means that the coverage is limited to the same areas for the most part that GlobalStar covers.

Since GlobalStar is dependent on ground stations (due to their "bent-pipe" architecture), parts of some continents (such as areas of Africa I visited while climbing Kilimanjaro), all of Antarctica, and areas beyond 80 degrees latitude (north and south, though for practical purposes, it is more like 75 degrees), along with major parts of the oceans (including Easter Island, where I will be in July) are not covered. These coverage holes do not affect most Trailspace readers, but are worth consideration if you'll be traveling to farther-flung locales.

SPOT has several messaging programs, ranging from a basic transmission to your team of five plus the 911 emergency message, to tracking and rescue insurance. The full package costs about $160 per year, automatically renewed (unless you cancel 30 days before your expiration date — there has been some discussion on Trailspace about the automatic renewal appearing on your credit card bill without notification beforehand, so mark the date on your calendar).

The forthcoming DeLorme PN-60w GPSR and SPOT Satellite Communicator combo

The second new SPOT package will consist of a DeLorme PN-60w GPSR and a SPOT Satellite Communicator. It is due out this spring. The two units will communicate wirelessly (the "w" suffix on the PN-60w) via a WiMax-like protocol, giving a several mile range. The GPSR will determine the location and will be capable of having text messages inserted to be transmitted via the SPOT/GlobalStar digital messaging system to a group of five selected individuals (or a larger group via the Share service).

The big step-up over the SPOT 2 (besides the added price of the PN-60w) is the performance of the PN-60w, which is a big improvement over the PN-40 GPSR (I have a PN-40). The two units' link capability means that, in principle, the user could leave the Communicator at the campsite in a location with a clear view of the sky, while the user goes for a day hike, sending important messages to his "team." The various subscription options have not been announced yet.

We hope to have a SPOT 2 for review in the near future, and perhaps the Delorme-SPOT combination in the late spring. However, the ACR PLB's cannot be tested in full, since that would activate a full-scale search and rescue operation.


Responsible Beacon Usage

Personally, I have reservations about the proliferation of "social networking" invading the wilderness. Texting, Twitter, Facebook, instant messaging, e-mail, and other forms of communications are rampant and increasing all around us (like it or not). It is one thing to have those capabilities in the city, another thing entirely to bring them into the backcountry. However, there is obviously a demand and a market for these functions, as evidenced by the units mentioned above.

I discussed with the locator companies the issue of responsible usage and incidents involving false alarms and "taxi calls" via various beacons. No beacon manufacturer is immune to this potential problem, along with people using their cell phones to call in a GPS-derived location. During Outdoor Retailer last month, I talked as well to guides and search-and-rescue members about this issue. I will write a more extensive discussion later, but for now, I will mention two incidents of repeated false alarms, one each for SPOT and ACR.

The SPOT incident has been mentioned before on Trailspace. Two men and their sons were hiking the Grand Canyon in September. They were ill-supplied with water. On arriving at a water source, whose quality they were uncertain of, they used their SPOT to summon the rangers. Later, they were again running low on water and summoned the rangers via their SPOT again. By the time the rangers arrived, they had moved on and found a suitable water source. A similar call resulted in the rangers forcing the four to be evacuated and to be barred from the park (the helicopter ride was not cheap!). When asked, the four said that they would not have undertaken the hike without having the SPOT in their possession.

The ACR incident is ongoing. Someone unknown is in possession of an unregistered ACR PLB in Colorado. International law requires registering PLBs before using them, a requirement apparently unknown to this owner. For the past several months, this person has set off the rescue function of his or her PLB four or five times in a weekend. Even though the unit is unregistered and the owner/user unknown, the local SAR unit is obliged to conduct a search.

The identifier allows determining the store where the unit was sold, but, since it is unregistered, not the owner. It may be that the user is unaware that he or she is setting off the rescue call, or it may be that he or she is doing so intentionally. The guide and SAR people I talked to from that area said that they are getting very tired of tying up the resources that might be needed (and on one occasion were needed) for a real emergency. The guide stated strongly that he believes that these units should not be sold to the general public.

To my mind, some fundamental education in personal responsibility and responsibility toward others is needed for users of beacons. Both SPOT and ACR stated that they are considering a public education campaign to educate buyers and potential users about the consequences of non-emergency usage.


"Personally, I have reservations about the proliferation of "social networking" invading the wilderness. Texting, Twitter, Facebook, instant messaging, e-mail, and other forms of communications are rampant and increasing all around us (like it or not). It is one thing to have those capabilities in the city, another thing entirely to bring them into the backcountry."

Hard to say it better than that. We need to fight "market demand" with philosophical principles. Not a fair fight by any stretch of the imagination, but it is good to make some noise on something this important.


The post was about locator beacons, not about communications devices. I have been called both good things and bad things because I do not carry any electronics besides a GPSR. Communications devices are not an invasion unless you are camped so close to someone as to hear them on their cell phone or to read their text messages, so while I may agree that I prefer not to take them, I do not see how the word "invading" is very meaningful, either to the topic or to my wilderness experience.

Just wondering whre yer coming from and why you care, its not boom boxes afterall.

Jim S

The "texting" functions of the ACR and SPOT described are one-way, and hence more like writing a blog that is transmitted "in the blind". You do not know whether the message has actually been relayed, since there is no ACK function and no way of receiving a response (except the SAR team arriving to bail you out).

However, that said, the line between these devices, which were originally designed as emergency-only devices, are getting awfully close to the satphone function. Some friends of mine who do long-distance "unsupported" adventure travel (example is Hannah McKeand) use the digital service of Iridium to send and receive status reports, weather updates, etc along the way (more efficient and a lot cheaper than the voice link). If you look at her Gallery, the 2006 Antarctic expedition, 3rd row 4th image, you will see me. While I feel that use of such communications links in extreme conditions and where the individual or small group is isolated literally days from any aid in case of emergency, is justified, the big problem is that it is turning the wilderness experience into an extension of the urban environment, where everyone has to be "connected" 24/7. The people like Hannah are not connected 24/7, but only for a couple minutes a day to relay information to their sponsors. Most of the 24 hours is completely alone. The radios have been known to fail, so that they are out of communication for days or weeks. They are not dependent on the com links. The direction for the "average Joe" heading into the woods, on the other hand, is a continuous video and audio link - nowhere close to a wilderness experience.

By the way, Jim, I am headed back to Alpine Lake (probably all the way to Duck Lake) this weekend. Wish you could join me again.

You cannot stop the march of technology, nor would you necessarily want to. The availability of devices to make difficult what was once impossible is a gain in my experience. The battle of ideology will always be an academic one, and enjoying remote wilderness will always be about how much of yourself you put into it, not about how easy it is to extract wonder out of it. Those who arrive with comm-link in hand may not be respecting their situation. Of course, they may also simply be keeping loved once back home in-the-loop and aware of their safety and security. That, also, is gain.


the last time I was up there a huge fire was sweeping through the area. My heart was broken seeing 300 foot flames in my favorite camping area, we hiked north over the ridge instead and looked down on it. My favorite spot is the granite ledges above the lake on the north east corner, I'll be interested in how it fared. Have a great trip, wish I could join you.

Jim S

Are digital cameras also a bad thing in wilderness? They sure let us relive our experiences and make us want to protect that country all the more.

Jim S

Are digital cameras also a bad thing in wilderness? They sure let us relive our experiences and make us want to protect that country all the more.

For some of us, the camera is an essential.

I'm required to use a bear canister. (FED)

I'm required to pack out what I bring in. (LNT)

I'm required to wear a helmet when I am not seated with a seat belt when on wheels or skis. (STATE)

I'm required to carry a SPOT on extended solo outings. (SPOUSE)

The former for the bear's sake; the LNT for your sake; the helmet so that they can find some of the messy pieces in one convenient package; the SPOT for the insurance to be filed promptly.

Lots of different requirements, some we take for granted and others for the good of all. I think my wife would like that I wear a locator anklet when in civilization so she knows if dinner will be late, and for peace of mind (if I remember to push the 'Hi Mom' button often enough) and to track progress or for a pickup/delivery. My kids think the Google map thing is really cool. There is a heated discussion that I really do go slowly and if I really am not near cardiac arrest. The default if I forget or the unit goes dead, is that I am ok. Just like before.

I am sure that inexpensive two way remote conversations are not far in the future.

I like that they have secured the 'send the cavalry' button somewhat. However, when you need to push it, it probably should be as available and unambiguous as possible. For my peace of mind when things are about to get really expensive, it would be nice to have a 'Gotcha' return signal. To cut down on the things I have to remember to bring along, it would also like the idea of an included SAR standard local frequency beacon to be used to help find and dig me out of the snow, or when they get close they know to look on THAT side of the wall. I'd either use the local frequency full time when playing in the snow with others, or it would come on automatically when I hit the 911 button.

Good summary Bill, tnx.

You have to wear a helmet skiing? Cross country too? What state do you live in?

On the other hand, I love my downhill helmet and often wear it cross country skiing anyway cause it keeps my head warm, doesn't interfere with my vision, and what the heck, I might hit a tree in the back country.

Jim S

This post has been locked and is not accepting new comments