Avalanche Beacons
By John Walter

Usually, gear reviews have a light-hearted tone to them. Let's face it, doing field tests on outdoor gear is what most outdoor enthusiasts dream about, and gear's function is to enhance your outdoor experience. However, this review has a more serious nature. Avalanche beacons are used to aid in the search for victims buried in an avalanche, a deadly prospect. Use of avalanche beacons does not usurp the importance of correct route finding while traveling in the backcountry. If you have to use an avalanche beacon, then ultimately somebody made a mistake and lives are at stake.

Time is crucial in the finding and recovery of an avalanche victim. Nine out of 10 avalanche victims will survive if they are found within the first 15 minutes. Once a victim is completely buried, there is only a one in three chance that they will be found alive. Two thirds of avalanche fatalities are from asphyxiation. The only reliable way to find an avalanche victim is with the use of an avalanche beacon.

However, a recent study in the United States shows that recreationalists, people who travel in the backcountry by ski, snowshoe, snowboard or snowmobile for recreation, cannot use an avalanche beacon fast enough to save the life of a buried victim . The average search time was 32-35 minutes. After being buried for 30 minutes, the survival rate of an avalanche victim drops to about 30%. The same study shows that spot probing for a victim, a totally random search method, resulted in a faster search time.

Why the long search times? It's because an avalanche beacon has never been considered user friendly, and unless a person is an avalanche professional, there is little chance they will practice regularly with one. Recreational backcountry skiers would rather spend their time skiing than practicing with their beacons. However, the digital beacons that have come on the market in the last few seasons are addressing the issue of ease of use, which can translate to faster search times.

How beacons work

Additional Avalanche Safety Items

Life-Link Snow Study Kit

SOS SB & Sled Bug

Backcountry Access Shovel/Probe Combo

Avalanche Rescue Beacons--A Race Against Time

Black Diamond Avalung

Avalanche beacons work on the principle of electromagnetic induction, much the same way a transformer works. An electronic pulse is sent through a coil wrapped around a rod to create a signal in the form of an electromagnetic field. This magnetic field is exactly the pattern of a magnetic field of a bar magnet. The coil, or antenna, in the receiving beacon picks up and interprets that signal. The receiving beacon then translates the signal to a format that the user can understand, usually an audible beep. In simple terms, the louder the beep, the closer you are to the sending beacon.

All beacons employ analog technology to send and receive the electromagnetic signal. The difference between analog and digital beacons is that digital beacons use digital processing to interpret the signal.

Analog beacons have undergone few changes since their introduction 30 years ago. However, these few changes have been significant. In the 1980's beacon manufacturers changed the frequency of the beacons from 2.275 kHz to 457 kHz, giving a much greater search range to the beacon (avalanche beacons went through a dual frequency period during the change period). Another significant change has been the addition of visual indicators on the beacon. The human ear does not respond to changes in volume well so these visual indicators were added to the beacon to help the user interpret the signal strength.

Digital beacons use a microprocessor to interpret the signal strength, and in some cases, the relationship of the receiving unit to the sending unit. The digital beacons use LED or LCD readouts to display distance to the user. Although the distance readout isn't completely accurate, as long as the distance is decreasing you are getting closer to the sending unit. The digital beacons also translate the audible portion of their processed information into beeps with increasing frequency as the receiving unit gets closer to the sending unit. Most importantly, digital beacons let the user know when they are lined up with the flux line, or the electromagnetic field, of the sending unit. All digital beacons run tests on the unit upon startup. During these tests, the unit will tell you how much battery life is left.

There are three stages to searching with avalanche beacons. The first stage is actually finding the signal. Traversing downhill in the avalanche path from the spot where the victim was last seen, you quickly scan for the signal from the sending unit. The second phase of the search is called the fine search. Once the initial signal has been picked up the traditional means of getting close to the beacon has been the grid search method, or bracketing. This entails searching for the victim using increasingly smaller brackets at a 90-degree angle to each other. While still effective, the induction line or tangent method has replaced the grid search as the recommended search method. The tangent method uses the flux line, or curves in the electromagnetic field, to direct the user to the sending beacon. The final stage of the search is called the pinpoint search. Without moving the orientation of the beacon from that strongest signal, you lower the beacon to the snow level and use the bracketing method to pinpoint the victim within a few feet.

The frequency change in the 1980's that gave a greater search range to avalanche beacons was instigated by European avalanche professionals. They needed beacons that would cover large avalanches; typical of the avalanches they experience. The 457 kHz frequency enabled this, allowing them to complete the first phase of the search quickly. But, to the recreational user, a greater range is not necessarily a good thing. Recreational users tend to slow down considerably during the second phase of the search, the phase after the initial signal has been picked up. Digital beacons have a smaller range than their analog counterparts.

Beacon Reviews
With that introduction out of the way, let's get to the reviews. I reviewed 7 different products in this review, three analog beacons and four digital. I tested the beacons for ease of use, both in the beacon search and the harnessing system, and for comfort. Let's face it, the more comfortable it is, the more likely a user will wear it. All beacons should fit comfortably once the harnessing system has been adjusted correctly. However, female testers found that beacons worn horizontally were more comfortable than ones that worn vertically. I reviewed only beacons that are available for the North American market.

Analog
Ortovox F1
SOS F1-ND
Pieps 457 Optifinder

Digital
Tracker DTS
Ortovox M1
Arva 9000
Red 457 (Barryvox 3000)

Ortovox F1 Focus

The Ortovox F1 Focus is probably used by more snow and avalanche professionals in the US than any other beacon, and the standard by which other beacons are judged. Ortovox is a German beacon manufacturer.

The F1 has an ergonomic design and the 3 point harnessing system is easy to use and allows the beacon to hang comfortably in a horizontal position. It uses a bayonet plug to switch the beacon on, meaning to wear the beacon it has to be turned on. The harness system allows the beacon to be worn by the user during searching, however, pinpoint searching would be difficult while wearing the beacon. The F1 has instructions on how to wear it and how to search for a victim silk-screened on the body of the beacon.

I found the F1 to be easy to use. The switch from transmit to search takes two hands but is easily done. The F1 has a good quality speaker that can emit a piercing beep and has an jack for optional earphones. It has a directional arrow to indicate which way to hold the beacon during searches. The F1 operates up to 300 hours on batteries and the control light flashes red when batteries have less than 50 hours of operation left. It has 3 lights for optical display to show the strength of the signal. Generally, our testers liked the F1 Focus.

The F1 Focus is distributed by:
Ortovox USA Inc.
603-746-3176
http://www.ortovox.com/

and also distributed by:
Climb High
802-985-5056
http://www.climbhigh.com/

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SOS F1-ND

The F1-ND from SOS, a Canadian company, is virtually a clone of the Ortovox F1 Focus. The differences are mainly cosmetic. The beacon hangs vertically instead of horizontally. The harness system is a simple design and easy to use. The F1-ND also uses a bayonet plug and has instructions silk-screened on the case of the beacon. It has the same basic features of the Ortovox F1. The F1-ND is easily operated and has no bells or whistles. Again, the switch to transmit is easily done with two hands. It has 4 lights to visually indicate the strength of signal, one to notify the user to turn down the volume knob. The range on the F1-ND is a 90 meters instead of 80.

The F1-ND is manufactured and distributed by:
Survival on Snow Inc.
780-973-5412
http://www.sos-find.com/

also distributed by:
888-90-CLIMB

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Pieps 457 Optifinder

The name Pieps is synonymous with avalanche beacons. Introduced in 1970, the design of the Pieps line of beacons has changed little. It is reminiscent of the older, lower frequency beacons. This helps to keep the price of this beacon low. At $239, the Pieps 457 Optifinder is the cheapest beacon in our review.

This beacon is one streamlined unit. Upon first look, the Pieps looks incredible simple, and it is. It is both easy to use and relatively comfortable. The Pieps isn't ergonomically designed and hangs vertically in the harness system.

The on/off switch seconds as the access point to the batteries. Like the Ortovox F1 and SOS F1-ND, the indicator light on the flashes red when there are less than 50 hours of operation left on the batteries. The Pieps will operate approx. 300 hours on fresh batteries.

Switching to search mode with the Pieps entails pulling out the volume control knob. Changing back to transmit mode is a cinch. However, care must be taken to make sure that the volume control is in the start position at the beginning of the search. The volume settings are difficult to see, especially while searching. The 4 LED lights visually indicate signal strength and notify the user when to turn down the volume. The Pieps has a jack for optional earphones.

The Pieps 457 Optifinder is distributed by:
Advanced Base Camp
http://www.advancedbasecamp.com/

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Tracker DTS

The Tracker DTS, manufactured by Backcountry Access of Boulder, Co., was the first digital beacon on the market. They released their first product in 1997 and have continued to update their beacon every year. Also, until this year, they were the only dual antenna beacon out there. The benefit from a dual antenna is that you get a three dimensional interpretation of the signal. As one reviewer put it, it's like seeing with two eyes instead of one . The dual antenna allows the Tracker DTS to tell you when you need to adjust your flux line during search mode.

The harness system on the Tracker DTS has been updated this year. The beacon hangs horizontally. Our female testers universally thought this was the least comfortable horizontal harness that we reviewed. Even male testers commented that the beacon felt like it flopped around. However, this beacon goes on easily and the harness allows you to stay tethered to the beacon while in search mode.

The signal interpretation on the Tracker DTS is purely digital.The signal is picked up and processed by the unit and then transmitted to the user as varying frequencies of audio signals. It also uses LED readout to tell you the distance (roughly) from the sending unit. The nicest feature of the Tracker DTS is the directional arrows. They tell you which way to move to adjust your flux line to the strongest signal while searching.

Our testers really liked the Tracker DTS. It has a simple interface for the user (2 buttons). Switching to search mode is as easy as holding the big red button down for 3 seconds. It notifies you if there are multiple burials and zeros in on the closest signal when within 15 meters. At the beacon competition of the 1998 Avalanche Professionals Conference, the Tracker DTS wasn't allowed because it was considered to be an "unfair advantage".

The Tracker DTS is manufactured and distributed by:
Backcountry Access
303-417-1345
http://www.bcaccess.com/

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Ortovox M1

The M1 is Ortovox's introduction to the digital market. The M1 uses a combination of analog and digital processing to guide help the user in the search. Audio output is exactly the same as the analog beacons. The digital viewfinder gives a readout of the approximate distance and signal strength so the user can easily adjust the flux line. The M1 even tells the user when to turn down the volume knob.

The harnessing system on the M1 is somewhat convoluted. On most beacons the harness actually supports the unit with the strap that goes over the shoulder or around the neck. The strap around the waist, however, supports the M1. It felt bulky and had a tendency to slide downward while traveling. Although the harness is unlike any other beacon, it too powers the unit for search. Switching the unit to search mode consists of popping the quick lock out, allowing the harness to stay tethered to the body for easy searching. However, care should be taken when switching to search as one of the spring loaded locking button popped off several times.

While our testers didn't like the harness, they liked searching with the M1. The combination of analog audio and digital viewfinder searching should help ease the experienced user into the digital market. The only drawback is that there is no backlight to the LCD readout. Searching in the dark would require a headlamp, which you would have to use anyway.

The M1 is distributed by:
Ortovox USA Inc.
603-746-3176
http://www.ortovox.com/

and also distributed by:
Climb High
802-985-5056
http://www.climbhigh.com/

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Arva 9000

The Arva 9000 is one of the more comfortable beacons on the market. The harness is very simple and easy to use, letting the beacon hang in a vertical position. The beacon is powered on by a plug attached to the shoulder strap, so to wear the beacon it must be turned on. Searching with the beacon tethered to the body was difficult, though.

The 9000 is pretty simple to use. It has a small LCD screen to display relative distance from the sending unit. Lights notify the user when they are aligned with the flux line and when there are multiple burials. Switching to search mode consists of pulling out the large red search switch. Change in the frequency of the audible output notifies the user when they are within 10 meters and again when they are under a meter.

The major drawback of the Arva 9000 is that it has a slight delay while it processes the signal. Care must be taken to when adjusting to the flux line. I always felt I was one signal pulse off while searching. I spoke with the distributor about this and he told me that shipping models have addressed this problem by increasing the pulse rate, so the processing delay shouldn't be an issue.

The Arva 9000 is distributed by:
Climb Axe Ltd.
503-236-9552
http://www.climbaxe.com/

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Red 457 (Barryvox 3000)

A brand new model of digital beacon is the Red 457 manufactured by Swiss beacon company, Barryvox. The 457 sports dual antennas like the Tracker DTS. The 457 is the smallest, lightest, most compact beacon on the market.

The Red 457 is a unique beacon, from the look down to the features. Adopting the trend of the computer industry, the case of the 457 is a translucent blue, reminiscent of the iMac. But the nicest feature of the 457 is that it is completely customizable to the user. You can set the beacon to be strictly analog, digital or a combination of the two. This enables the user to use the settings that best suit their searching methods.

The harnessing system on the 457 is also very unique. The harness consists of a pouch with two straps, one for the shoulder and one for the waist. The beacon slips into the pouch and is tethered with an elastic cord and secured with a fastex-tyoe buckle. The beacon hangs in a slanted position, much like the radio harnesses that the Ski Patrol wears.

The Red 457 is a slick unit. A large LCD that is backlit displays data to the user. Like the Tracker DTS, the dual antenna allows the user to adjust to the flux line on the fly. This beacon notifies the user of multiple burials and then switches the speaker to analog and locks onto the strongest signal within 30 meters. It also has instructions for search silk-screened on the beacon.

The Red 457 has a few drawbacks like the same processing delay problem as the Arva 9000. Also, if the buttons protruded instead of being recessed, they would be easier to use with bulky gloves.

The Red 457 is distributed by:
Red Corp.
603-746-3176
http://www.red-corp.com/

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Conclusion
Like other markets, digital technology is changing the avalanche beacon market. Overall the digital beacons were easier for inexperienced users to search with. However, this doesn't make the analog beacons obsolete. When doing research for this review, three words kept popping up: practice, practice, practice. Practice and familiarity with your particular beacon is more important than the features of beacons with digital technology.

John Walter (Walt) is the climbing editor at GearReview.com. Walt spends the winter frequenting the mountainous backcountry of Utah's snowy Wasatch Range.