This page discusses the range (distance) at which an avalanche transceiver receives a signal. Remember that during the signal search you can slowly rotate your beacon in all orientations to increase the likelihood that your antenna will line up with the transmitting beacon (the Mammut Pulse and Ortovox S1 have motion sensors and should be held horizontally).

Rescuers Testing Beacons

The following graph shows the distances at which the avalanche beacons received a usable signal. The bars show the distance with the transceivers aligned (i.e., the best orientation).

This graph summarizes 201 range tests (view the testing details). I only tested one or two of some models (e.g., the Barryvox 2000 Ext and Pro, Mammut Pulse, ARVA 9000/3Axes/Evo3, Ortovox Patroller, Ortovox D3, Pieps Freeride, SOS, and Tracker2). The other models were tested extensively (e.g., 3 Ortovox 3+'s, 3 Ortovox S1s, 4 Ortovox X1s, 6 Barryvox 3000s, 9 Tracker DTSs, 13 Pieps DSPs, 15 Ortovox M2s, etc.). Even with this large sample of transceivers, differences of 5 meters or less are probably immaterial.

I also tested the range that avalanche transceivers can transmit a signal. You can read those test results here.

A transceiver's range will vary significantly if the transmitting beacon is not at the correct frequency. it will also vary based on other factors such antenna orientation and battery strength.

Remember that the transceivers with the longest reception range are almost always single-antenna analog. That means they report a signal at a long distance but do not provide a directional indicator that points toward the victim. As explained in the test details, the analog distances in the following chart were when an extremely faint (but undeniable) audio signal was heard. You will not get these analog ranges if there is any background noise. Likewise the digital ranges are with the best case antenna alignment and the transceivers were given a long time (up to 10 seconds) to lock onto the signal.

Avoid the tunnel-vision trap of believing that transceiver range is the only important criteria—it isn't. Range is certainly important, but the difference won't matter if you fumble during your search (possibly due to spikes) or if you can't identify and locate multiple burials. Knowing the appropriate search strip width for your transceiver is more important that having a transceiver with a long range. As explained on the discussion on searching an avalanche, it is better to spend a few extra minutes searching a narrower path during the signal search than to end up at the bottom of the slide and have to repeat the entire search.

You can click on the transceiver names (or bars) in the following graph to read more about that avalanche beacon.

Dual Mode Beacons

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Mammut Pulse

The Barryvox 3000, Ortovox X1, and Ortovox Patroller start in analog mode and then automatically switch to digital mode. (This behavior can be modified on the Barryvox 3000 using a custom setting.) The ARVA Advanced, ARVA 3Axes, Barryvox 3000, and Mammut Pulse can be quickly switched between analog and digital mode. The Ortovox S1 can be changed to analog via a menu option.

On beacons that support analog and digital modes, two distances are shown in the above graph. The analog distance is labeled "(A)" and the digital distance is labeled "(D)". You can see that there is only a 10 meter difference between the analog and digital range of the ARVA Advanced whereas the Ortovox Patroller has a 55 meter difference (the Patroller had one of the best analog ranges at 75 meters, yet in digital mode it didn't display a direction arrow until it was within 15 meters of the victim).

The Pulse has an "analog-only" search mode that significantly increases its range. Unfortunately, this mode was not used when measuring the Pulse's analog reception range as shown on the range chart. Learn more about the analog-only search mode.

Calculated versus Recommended Search Strip Widths

IKAR is an international organization that provides recommendations for mountain rescue know-how. They recommend that avalanche transceiver manufactures publish a recommended search strip width that is "about equal to 1.4 (± 0.1) times the realistic maximum range..." That distance is intended to allow for sufficient overlap between search strips.

The following table shows the maximum ranges that were measured during the above range tests, the calculated search strip width (i.e., the maximum range multiplied by 1.4), and the manufacture's recommended search strip width. You can see that all of the manufacture's search strip widths are well within the calculated values (although the Tracker2's recommended width is fairly close to its calculated width).