Wearing an avalanche transceiver and carrying a probe and shovel are essential if going into areas with a potential avalanche risk. Essential too is practise in using the equipment.
Like many people these days I’m carrying a mobile phone and sometimes use a GPS. I was aware that electronic items could have an effect on avalanch transceivers. Transceivers emit a signal on 457 mhz until switched to “search mode” when they are used to home in on this emission.
The effect was demonstrated recently in dramatic fashion. I had buried my rucsac with my transceiver to simulate a casualty. The two searchers switched their transceivers to “search” mode. Immediately it became apparent that the two transceivers were behaving in a peculiar manner. Unexpected direction indications; sudden loss of signal and “freezing”. What was going on!
We decided to get to the bottom of this issue by experimenting with different combination and permutations of phones and GPS’s. The culprit was a Sony smartphone. If this was in proximity in any mode other than “off” the transceiver was rendered inoperable.
There’s only one conclusion: switch off all telephones when using transceivers.