ARVA 3 Axes Mode D'emploi page 10

useful information:
Move forward SLOWLY to avoid going too hastily in the wrong direction. The entire surface of the avalanche must be investigated.
When searching for a victim or testing the unit, stay away from electrical equipment (high-voltage power lines, radios, mobile
phones, etc.) or impose radio silence (these are just a few examples). This is applicable when using any ARVA-type transmitter-
receiver. The distance indicator indicates progress along a field line and not a distance in metres.
Simply press simultaneously on the + and - buttons for 3 seconds to flip from Standard (numerical) mode to Advanced
(analogue) mode (Advanced logo and sensitivity level are displayed on the LCD screen). Repeat this operation to return to nu-
merical mode (the logo and sensitivity level disappear from the LCD screen). This can be done at any time, even if rescue workers
have begun their search in Standard (numerical) mode.
We shall now take a look at the two main modes and study an example of a search in the case of multiple victims. The cases
presented are «typical» ones. With training and experience, the user can change from Standard (numerical) mode to Advanced
(analogue) mode depending on how familiar he is with the device and the situation in which he finds himself.
Case of a single victim
standard digital mode standard digital mode
■ Primary search (approach phase) (cf D1)
2
• Pull SEARCH.- The device is automatically in completely auto-
matic numerical mode. The LCD screen displays the arrow diagram
continuously until you pick up a signal from the victim.
• Move backwards and forwards across the avalanche as shown in
diagram B if you are the only rescuer or diagram C if there are several
rescuers.
• Hold the ARVA horizontally, pointing it downwards, and sweeping
it slowly from left to right and right to left (making an angle up to
180°)
• Continue until you pick up a first clear signal (directional arrows and
distance indicator light up)
N.B: If the ARVA has already picked up a signal it will go directly to
the secondary search.
■ Secondary search (locating phase) (cf D2). This phase starts
when the victim's signal has been picked up.
• The ARVA gives you a distance indication on the LCD screen and
one of the directional arrows lights up.
• As soon as one of the directional arrows lights up, point your ARVA
in such a way that the central diode lights up and head in that di-
rection. If the numbers decrease, you are moving closer to the
victim. If not, go in the opposite direction.
• Always try to make sure that the central diode is lit. Sweep
the unit gently in the directly in which the arrows light up. This will
enable you to cover the shortest possible distance before reaching
the victim. Continue moving forward until the distance indicator dis-
plays 3.0.
■ Final search (detection phase) (cf D3)
At this point, with the arrow lit up, lower the ARVA unit as close as
possible to the snow, pointing it in the same direction and keeping it horizontal. The beeps become faster and the
distance indicator keeps decreasing. Keep moving forwards as long as the number decreases. If it starts to increase,
return to the point where it is smallest and locate the victim using the cross technique, always pointing the ARVA
in the same position.
■ Cross technique: The ARVA must be moved as closely as possible to the snow, in parallel straight lines. Determine
the point along the line where the distance indicator displays the smallest number and the beeps are emitted very
close together or continuously. From that point, move perpendicularly and repeat the operation. The point at which
the maximum signal is obtained is vertically above the transmitter. If necessary, repeat the operation once or twice
to obtain a more precise position. However, it is not necessary to determine an extremely precise location using the
ARVA. In fact, it is usually faster to start searching with a probe as soon as the likely location has been determined to
within about 50 cm.
Notice3axes2008.indd 10 Notice3axes2008.indd 10
3 Axes 3 Axes
pinpoint
search
recherche
1, 7
finale
1, 6 0, 7
1, 5
secondary
5,0
search
recherche
secondaire
15
30
primary
search
recherche
primaire
1, 4
D
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