bca Tracker DTS User Manual page 7

Operating Instructions
(2) tells you, in approximate meters, how far you must travel
(1 meter = 1.1 yards or 3.3 feet). If the number on the distance
indicator is increasing, you are on the same axis as the victim's
signal, but moving in the opposite direction. Turn 180 degrees,
engage the center search light again, and continue your search
in the direction the Tracker is pointing. This is preferable to walk-
ing backwards, in which case the Tracker will often flash "SE"
rather than show a direction and distance. If you are stationary,
but the distance is significantly changing, you are probably
detecting the signal of another rescuer. Make sure all rescuers
are in search mode before continuing.
Flux lines
Figure F
The Tracker follows the shape
of the electromagnetic flux
lines coming from the trans-
mitting beacon' s antenna.
Your path during the fine
search will be either
straight (point A)
or curved (point B),
depending on the
orientation of your
beacon when the
signal is first captured.
Note: the Tracker' s transmit-
ting antenna (10) is oriented
at a 45-degree angle to the
long axis of its case,
as shown.
You may find that, while following the directional lights, your
route follows an arc. This is because the Tracker DTS performs
the fine search using the "flux (or induction) line" method (see
Figure F). It follows the shape of the electromagnetic signal, or
flux line pattern, coming from the transmitting beacon's antenna.
The distance displayed is the distance to be traveled along that
flux line, not the straight-line distance from you to the victim.
Pinpoint Search
The pinpoint search is the final part of the beacon search, which
is performed on foot with the beacon positioned at or near the
snow surface. The objective of the pinpoint search is to locate
where the signal is strongest and to reduce the area to be
probed.
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Operating Instructions
Move your beacon very slowly along the surface of the snow
during the final three meters of the pinpoint search. It can be
helpful to tilt the front of the Tracker down, although it is not
necessary. Ignore sudden fluctuations in distance and direction,
often followed by no distance reading and/or "SE" in the
distance indicator. This means you are very close. The lowest
reading will be near this point.
Pinpoint Search
Figure G
Cross-section
view
Transmitting Beacon
Bracketing: From the point where you have located the smallest
reading, it can be helpful to "bracket" at 90-degree angles to the left
and then to the right in search of a lower reading (bird' s -eye view).
Pinpointing on a line: You will encounter a "spike" reading where
the vertical aspect of the flux pattern is perpendicular to the search-
ing beacon (cross-section view). This is indicated by a suddenly
weaker signal (higher distance reading) and fluctuations or loss of
directional lights, and/or "SE" in the display. Search past the spike for
a lower distance reading along the line you've been travelling. If you
do not deviate from this line, it is not necessary to bracket.
From the point where you have located the smallest reading, it
can be helpful to "bracket" at 90-degree angles to the left and
then to the right in search of a lower reading (Figure G, bird's-
eye view). Repeat if necessary along both axes. Begin probing
at the lowest distance reading, in an expanding spiral pattern.
A T : P
DVANCED ECHNIQUE INPOINTING ON A
Until the Tracker is very close, it will point you in the general
direction of the buried beacon. Once you are within less than
Bird' s -eye
view
L
INE
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