Raymarine L1250DRC, Руководство пользователя

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Chapter 5: Adjusting the Display 5-15
Ch
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Ra
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3. If desired, press the
RANGE AUTO MAN
soft key to select
AUTO
range.
AUTO
range is indicated by the letter
R
in the status bar.
4. To adjust the shift, press the appropriate
SHIFT
soft key: Use the up soft key
to select a shallower shift, use the down soft key to select a deeper shift.
The image window is shifted up by the selected amount. Pressing the
SHIFT
keys sets the range to
MANUAL
.
5. Press
ENTER
to return to the default display.
Hunt Mode
HD Series Fishfinders feature a digital “Hunt mode” that automatically
searches for the bottom while the sounder is in Auto Range. If bottom cannot
be determined while
AUTO RANGE
is selected, the sounder pings the last
known depth, and then incrementally increases the ping depth to a maximum
value determined by the transducer type (see
Table 5-3 ) until the bottom is
found. If bottom is not found, the sounder returns to the original depth and
repeats the process.
If AUTO FREQUENCY is also selected (see Selecting the Frequency on
page 5-16 ) when the sounder completes the auto range hunt process, the
process is repeated in the other frequency. If
MANUAL FREQUENCY
is selected,
hunt mode only continues in the selected frequency. This process continues
until bottom is detected or you switch to manual range mode.
The maximum depth to which Hunt mode searches is determined by the high
power output of the transducer, as follows:
For example, let’s say a L1250D with a 1000 W transducer is set for auto range
& auto frequency and bottom is currently detected at 500 ft using 200 kHz.
The bottom signal becomes lost, so the unit switches to Hunt mode. Pinging
begins at 500 ft using 200 kHz and increments to 1500 ft. If bottom is not
detected, the sounder switches to 50 kHz, repeats pinging at 500 ft, and
increments up to a maximum of 5000 ft. If bottom is still not detected, the
sounder returns to 500 ft using 200 kHz to continue the process.
When bottom is found, Hunt mode ceases and the sounder adjusts to the range
and frequency appropriate for the new depth.
Table 5-3: Maximum Depths for Hunt Mode
200 kHz 50 kHz
600 W
1000 ft (400 m) 3000 (1000 m)
1000 W
1500 ft (500 m) 5000 (1700 m)
RANGE
AUTO MAN
81213_1.book Page 15 Monday, March 17, 2003 1:14 PM