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3.2
Headphones
Headphones can assist in the early stage of a search when the signal is very weak. When outside
the range of a transmitter, the Vecta
static noise. The EMI can overpower the signal of a distant transmitter. At times the oscillating tone
of a BEACON can be heard faintly amidst the static by listening with the headphones. When this
occurs the BEACON is located in the general direction that the Vecta
direction.
3.3
Searching for a BEACON
Slowly rotate 360°, taking about 2 minutes, listening for a 121.5 MHz BEACON tone. The LEDs will
scroll up and down as you rotate nearer and farther away from the BEACON's signal. The FINE
scale will climb when facing the BEACON. There are two indication modes for deciding the
direction of the BEACON: You must take your time when rotating and keep the Vecta
position as you turn to minimize the effects of your body on your power readings.
Tone Mode: When just coming into range of the BEACON (Weak Signal) an audio tone will
be your guide for direction. A louder tone will be received from the BEACON direction. If no
tone is heard, rotate the unit in your hand 90° and scan the horizon all around (360°)
listening for a tone. See section 3.4 for an explanation of polarization. If a tone is heard, the
BEACON is in range, and the rescue can continue with greater pace.
Visual Mode: When Audio Tone has stabilized (as signal strength increases), the LED
Signal Meter will scroll in an upward fashion indicating an increase in signal strength, as you
approach the BEACON. Signal strength can be observed in two different modes: COARSE
and FINE. See section 4.0 for an explanation of COARSE and FINE signals.
3.4
Polarization of the BEACON and the Vecta
The ability of the Vecta
polarized with the antenna of the transmitter.
In a blind search, the polarization of the BEACON's antenna is unknown. To polarize the antennas
rotate the Vecta
antennas from a horizontal position to a vertical position so they are in alignment
2
with the transmitting BEACON's antenna. The Vecta
the unit are in a perpendicular orientation with respect to the transmitting antenna.
The Vecta
is polarized for maximum signal strength when the antenna blades of the unit are in a
2
parallel orientation with the transmit antenna.
Polarized with Beacon
will pick up ambient electromagnetic interference, (EMI), or
2
to pick up a weak signal is improved when the antenna of the Vecta
2
Figure 5
2
is not polarized when the antenna blades of
2
Not Polarized with Beacon
6
is pointed. Move in that
2
in the same
2
Figure 6
Y1-03-0227 Rev. A2
is
2
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