• Skip to primary navigation
  • Skip to main content
  • Skip to footer
  • Facebook
  • Instagram
  • Français
  • English
Simply Savoie Logo

Simply Savoie

Guided walking – snowshoeing – via ferrata in the French Alps with Mark Tennent

  • Home
  • Snowshoe
    • Snowshoe Walking in the Three Valleys
      • Guided Snowshoe Walks Courchevel
      • Guided Snowshoe Walks in Meribel
    • Snowshoe Walking in the Vanoise
    • Guided Snowshoe Weekends in the Vanoise
    • Snowshoe Walking in the Beaufortain
    • Guided Snowshoe Weekend in the Beaufortain
    • Snowshoe Traverse of the Beaufortain
    • Snowshoe Traverse of the Chartreuse
    • Snowshoe Walking in the Haute Maurienne
  • Avalanche Courses
    • Introductory Avalanche Search and Rescue Training Course
    • Intermediate Avalanche Search and Rescue Training Course
    • Avalanche Training Essentials Course
    • Avalanche Awareness Talks
  • Via Ferrata & Rock Climbing
    • Rock Climbing
    • Guided Via Ferrata Weekends
    • Guided Via Ferrata Weeks
    • Via Ferrata in the Hautes-Alpes
    • Via Ferrata holiday in the South of France
  • Walking
    • Centre Based
      • Walking in the Maurienne – Vanoise
      • Walking in the Vanoise
      • Walking in the Beaufortain
      • Walking in the Aravis and Bauges
      • Photography and Walking in the French Alps
    • Trekking
      • Tour of the Vanoise
      • Tour du Mont Blanc
      • The Haute Route – Chamonix to Zermatt
      • The Tour of the Beaufortain
      • Corsica – GR20
      • Tour of the Ecrins
      • Tour of the Queyras
      • 3000m Summits Week
      • The Verdon Gorge & the Haute Provence
  • Custom Guiding
  • About
    • Mark’s Blog
  • Contact

Transceiver

Formation DVA Avalanche

Bonjour mark

Super merci. Encore merci pr cette belle journée. J’ai appris pleins de choses et ce, dans une très bonne ambiance et avec bonne humeur ! Tu as contribué à cela. Je vais sûrement faire la suite des formations. On se croisera peut-être

23 janvier 2021

Avalanche Transceiver Search

The Perils of Old Avalanche Transceivers

If you, or a friend, are still using an old (c. 10 years or over avalanche transceiver) it’s time to consign it to the bin! And no, don’t sell it on Ebay!

Technology changes

Really old transceivers worked on analogue technology. There were no visual direction or visual signal strength indicators. Your only guidance was by the volume of the ?beeps? emitted and adjusting the sensitivity of the device. It required experience and regular practice to become proficient. They almost certainly had only one antenna.

After that came two antenna transceivers to help give directional guidance and range to the victim. Now the majority of transceivers are all using three antennae; and some now even four.

Groups with old (analogue) and new (digital) transceivers

Mixing the old with the new: old analogue transceivers transmit in such a way that they can mask the signals coming from a more modern receiver. So it’s not just you who may not be found you may also create problems for your friends!

Periodic Servicing

If it’ over 3 years have it checked over. Why you ask? The antenna(e) of transceivers can get broken. You may not be aware unless you carry out a full group type check. Here you may discover a drastically reduced range; amongst other anomalies. Is there corrosion that you can’t see?

Software Update

Make sure you are using the most up-to-date software for your transceiver.

Signal Drift

Transceivers work on the 457 mhz frequency. Old transceivers are prone to drift too far from this frequency with the result they are impossible to find!

The Effects of Consumer Electronics on Avalanche Transceivers

We see and potentially carry, more and more gadgets including: ?smartphones?, GPS devices, digital cameras with GPS built-in, GoPro’s, etc.

However the effects of ?Consumer Electronics? on Avalanche Transceivers is sobering. The long and short of it is ?turn it off?. (If carried they should be more stowed more than 30cm from the transceiver ? in a backpack).

The effect is most marked in the ?Search? (Receive) mode as the signal searched for is masked by the electronic ?noise? of the other device(s). This can make it very, very difficult to locate the victim and remember ? every second, minute counts.

Don’t forget that some digital cameras have a built-in GPS to location ?stamp? where photographs are taken. These too should be off and stowed at least 30cm from the transceiver.

The document in this link shows graphs clearly demonstrating ?The Effect of Consumer Electronics? on avalanche transceivers from ?Proceedings, International Snow Science Workshop, Banff, 2014? Link: http://arc.lib.montana.edu/snow-science/objects/ISSW14_paper_P4.13.pdf

Reading and Interpreting the Avalanche Forecast

Reading and interpreting the avalanche forecast is fundamental to reducing the risk of becoming a victim of an avalanche.

Despite daily avalanche forecasts available on-line and displayed in ski resorts there are still too many avoidable avalanche accidents.

Studies show that these incidents took place where predicted by the avalanche forecast. So, either people are not reading the forecast, or if they do they are not extracting the information in it.

The Avalanche Risk Scale

The European avalanche risk scale runs from 1 to 5. Statistics (from France) for the last 15 years show that on 44% of days the risk was at level 2 (with 14% of fatal incidents) and 35% of days were level 3 (with 56% of fatal incidents).

One of the issues is the perception of Level 3. It is seen wrongly, by many as a ?medium? risk when in fact it is ?considerable?. If the avalanche risk scale e.g. 2 is the only element of the avalanche forecast being read incidents will clearly follow and the statistics would lend credence to this conclusion.

The Avalanche Forecast

The avalanche bulletin itself contains a wealth of information.

Timescale ? at the top it gives the validity of the forecast and the level of risk. Sometimes it indicates an altitude with one risk level below and another above.

Compass ? here it shows which slopes are the most dangerous in terms of their orientation.

Type of avalanche(s) to expect ? This is divided into two types, natural releases and those caused by skiers.

Snowpack Stability ? Here a detailed description of the current stability of the snowpack. It may give information about recent weather patterns including wind direction and strength. There may also be more detailed information about altitudes where certain risks may be higher. This paragraph should be read carefully.

Depth of Snow (at a certain altitude) ? here it gives information on the quantity of recent snowfalls and what is predicted over the following 48 hours.

Weather forecast summary ? here it gives the altitude of when rain will turn to snow; the freezing level and wind speed at different altitudes along with the direction.

Snow depth off-piste ? here it gives the depth of snow at different altitudes on both north and south facing slopes. It also gives the altitude from which you can expect continuous snow.

State of the snow ? the state of the snow e.g. is it crusted, humid or powder.

Avalanche risk outlook ? here it shows whether the risk is staying the same, increasing or decreasing.

Time when the forecast was written ? here it gives the date and time that the forecast was prepared.

As you can see there’s a wealth of information that when read carefully substantially decreases the chance of becoming an avalanche victim.

Avalanche Transceivers and Electronic Equipment

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.

Footer

Useful Links

  • Offers
  • FAQs
  • Weather
  • Photo Gallery
  • Video Gallery
  • Privacy Policy
  • Terms and Conditions of Booking

Latest Articles

Stone Stacking in the mountains

Cairns A cairn is a man-made pile (or stack) of stones. The word cairn comes … [Read More...] about Stone Stacking in the mountains

Autumn via ferrata trip to the South of France

Finally the time came to run my first via ferrata tour in the South of France! Saturday, 28th … [Read More...] about Autumn via ferrata trip to the South of France

Follow Simply Savoie on:

  • Facebook
  • Instagram
  • Twitter
  • YouTube