bca Tracker2 Owner's Manual page 16

Special Search Techniques
In most cases, multiple burials are approached as a series of single
burials. However, special techniques might be helpful if the victims'
beacons cannot be turned off and there are several rescuers
available (so some can start shoveling while the best beacon user
continues searching). These techniques are only necessary for
close-proximity situations, where two or more victims are suspected
to be very close to each other. If the victims are located less than
about five meters from each other, then it is possible to move past
a signal without it being detected. If the victims are suspected to
be further apart than this, then it is quite simple to continue on your
signal search until the second victim's signal is captured and isolated
by your Tracker. In the case of suspected close-proximity multiple
burials (with more than one rescuer available), we suggest the
following special techniques:
Three-Circle Method: This technique involves remaining in SE
mode and making concentric circles around the location of the first
victim until another signal is detected. It is most effective in large
deposition areas and low-angle terrain.
Micro-Search Strip Method: This technique is more useful in
smaller debris areas, like those often encountered in guiding exams.
The user remains in SE mode and crisscrosses the debris pile in
strips three to five meters apart until the next signal is detected.
For detailed instructions on using the special techniques above, see
our Advanced Tracker Manuals at www.backcountryaccess.com.
Special Mode: For greatest efficiency in "special case" close-
proximity multiple burials, use special (SP) mode. This mode enables
the Tracker to display the distance and direction of signals other
than those of the closest beacon (Figures I, J). It also reduces the
Tracker's search "window" to the center three directional lights,
enabling the searcher to mask out beacon 1 and differentiate it
from beacon 2. SP mode is used to determine approximately what
direction and distance to go to get closer to beacon 2. Once you are
closer, always switch back to SE mode.
To use SP mode, hold the Tracker steady at the lowest possible
distance reading. Switch the Tracker to SP mode, then rotate—do
not sweep—the Tracker gradually until another signal is detected
(beacon 2), most likely with a larger distance reading. If the Tracker
is rotated more than about 40 degrees away from the signal of
beacon 1, that signal will disappear, allowing you to focus on the signal
from beacon 2. However, it is possible to capture more than one signal
in SP mode.
14