The Arva "Axis" has all the good features of the Mammut Pulse(and none of the daft ones IMHO) and the internals are (I think) Barryvox so possibly from the same stable. But - the Axis is £275 RRP. It seems a no brainer to me that if you want good technology and a "mark" function then the ARVA is stunning value especially as it's £100 cheaper. Reviews are excellent http://beaconreviews.com/transceivers/Specs_ArvaAxis.asp and a few friends in the Alps have used them and really like them. I hope to have a test one soon that folk can try at the Glencoe Beacon park
I can also get the Arva "Link" Beacon, but to be honest I see it as the same as the "Pulse" which will be outsold by the cheaper "Element". Lets hope Mammut waterproof them better as an MRT at the Glencoe Beacon park had twelve go down with water ingress and had to be returned to Mammut. Some ski tour folk were at the Beacon park with ARVA Evo's yesterday. They also seemed happy with the Evo which is the basic ARVA model.
I don't think my stance as the Tracker 2 as being the best and most reliable and simple to use beacon will change. But a lot of folk seem to want a "Mark" feature. Telling them that the 3 circle search method is just as fast doesn't seem to cut it with them, nor do they like to hear that digging the first person found out fast is what saves lives. Never the less this seems a good beacon and it gets a 5 star review so mark away. Give me a call if you want one.
The AXIS is the latest avalanche beacon in our product line, and it leverages the technologies and features developed for the Link.
It’s the most advanced and versatile device within its product category. Featuring both digital and analog search modes, a marking function, and a 50 meter search width band, it is the perfect answer for the advanced ski enthusiast looking for performance.
Features the exclusive Standby function, which integrates a motion sensor to secure the user in case of a second avalanche during the search process, while probing or shoveling.
Specifications:
- Digital and analog
- Search Bandwidth: 50 meters
- 3 antennas
- 4 AAA alkaline batteries
- Operating time: 250+ hours
- Manufacturer warranty: 5 years
- Weight: 9.2 oz, 260 grams
Hi Davy,
ReplyDeleteAnother interesting blog.
As an electronic engineer have always been interested in beacon technology.
The problem with the mark feature is that all the beacons transmit pulses with an approximate 10.1 mark to space ratio on exactly the same 457kHZ frequency.
So the only way to 'mark' a beacon is to ignore the time slot in which that beacon is transmitting. There are a couple of problems with this approach...
1) It is very easy to accidentally mark more than one beacon. With 2 beacons the chances of this happening are small (approx 10%) but very real. When it does happen it is very confusing. With 3 or more beacons the chances of masking multiple signals obviously increases significantly. With 4 buried beacons it rises to nearly 40-50%.
2) Also.... Marked beacons can sometimes become unmarked over time due to phase differences. The 10 to 1 mark space ratio is not exact and depends on the exact moment in time each beacon started transmitting.
If either of the above occur then is obviously confusing for the searcher and the only solution is to turn the beacon on / off (reboot).
Would agree - On paper the mark function seems like a nice selling point and it can be useful. However multiple burials still require training and an awareness of what is happening.
I also reckon that the only scenario you might use the 'mark' function is with multiple buried victims AND multiple (2+) searchers. Even with 2 searchers you may be better both probing / digging out the first victim, clearing airways and turning their beacon off ? Then searching for the second victim.... Though as you commented above people dont like the idea that, realistically, you cant locate and dig out multiple victims within 15 minutes.
Doug
Hi Doug. Did you seem my blog post from 6th Nov 2011 on signal overlap? Not being a techy I can't explain it as well as you, do but the conclusion is the same I think. Great afternoon up the hill yesterday. Paying for it today with the ipobrufen as my back was in and way yesterday!
ReplyDeleteGreat day up Glencoe yesterday Davy.
ReplyDeleteReally enjoyed getting in some laps with nae queues.
Just (re)read 6th Nov 2011.
Exactly the same 'signal overlap' effect.
By coincidence there is a wee sneak peak of the T3 on wildsnow.
Which does includes a mark feature.....
http://www.wildsnow.com/6589/temple-of-gear-day-2/
After meeting with, and doing some training with "Edge" from BCA I don't think they really believe in "mark" features because research shows it doesn't change outcomes. However, the commercial pressure is immense and they need to make money. Their products seem to be well designed and tested by folk out there doing the business so I think the T3 might be quite good. Simple things like taking off "auto revert" as a default setting because research from avy pros in the states showed it totally screwed up searches, and having a big button that the user could thump in off themselves to go back to transmit seem such obvious non tech ways of increasing speed and keeping it simple. That's my take anyway!
ReplyDelete