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This page discusses the range (distance) at which an avalanche transceiver receives a
signal. Remember that during the
primary 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 Pulse Barryvox and
Ortovox S1 have motion sensors and should not be rotated once you receive a signal).
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| 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 table summarizes controlled testing of more than 100 avalanche
beacons (view the testing details).
I only tested one or two of some models (e.g., the SOS, ARVA 9000, Ortovox D3, and Pulse Barryvox).
The other models were tested extensively (e.g., 4 Ortovox X1s, 6 Barryvox 3000s, 9 Trackers, 12
Pieps DSP, 15 Ortovox M2s, etc.). Even with this large sampling of transceivers, differences of 5 meters or less are probably immaterial.
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 to the victim. As explained in the
test details, the analog
distances were when an extremely faint (but undeniable) audio signal was
heard. You will not get these analog ranges if there is any background
noise.
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.
As explained on the discussion on searching an avalanche,
it is better to spend a few extra minutes searching a narrower path during the
primary 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.
Most beacon manufactures recommend a primary
search width of no more than 40 meters. The
BCA Tracker manufacture recommends a
primary search width of 20 meters. The
Pieps DSP and
Pulse Barryvox recommend a width of no
more than 50 meters.
Dual Mode Beacons
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The
Barryvox 3000
and Ortovox X1
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, Barryvox 3000, and Pulse Barryvox
can be manually switched between analog and digital mode. On
beacons that support an analog mode, 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 almost no
difference between the analog and digital range of the ARVA Advanced whereas the
Ortovox X1 had a huge difference (the X1 had one of the best analog ranges at 71 meters
and one of the shortest digital ranges of 33 meters--and the X1 doesn't display a
direction arrow
until it is less than 15 meters from the victim).
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