Avalanche transceivers have saved many lives and are an essential piece of avalanche equipment to take with you off piste.
Transceivers are used to locate victims who are buried under the snow - 90% of avalanche victims survive if they are found and freed after 15 minutes of being buried as it is usually not the force of the avalanche that kills, but the lack of air under the snow. Transceivers use electromagnetic waves which flow between the searcher's device and the victim's device. It then uses these waves to tell the searcher in which direction they should walk to locate the victim. Digital devices also show how far away the victim is from the searcher.
The number of antenna determines the transceiver’s accuracy – 3 antenna will mean that it is very accurate in ‘search mode’ i.e. it will show exactly when you are above the victim, and it will point you in the exact direction you must go to reach them. However, single antenna transceivers have a longer search range.