Lighthouse Raymarine gS 195, Инструкция по установке и эксплуатации

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detecting small fish. Use lower frequencies if you
require a large coverage beneath your vessel or if
you are in deep water.
• Medium frequency — non-CHIRP mode (e.g. 90
kHz) — Produces good detail at most depths, with
moderately wide sonar beam.
• High frequency — non-CHIRP mode (e.g. 160
kHz) — Produces a narrow beam and produce
a high resolution image. They are most useful
in shallower water (up to 1000 ft) and at higher
speeds.
• Low Chirp — CHIRP mode (e.g. 42 to 65 kHz) —
No fine-tuning is not needed as the CHIRP sonar
module will sweep the transducer’s available
frequency range in each ping.
• Med Chirp — CHIRP mode (e.g. 85 to 135 kHz)
— No fine-tuning is not needed as the CHIRP
sonar module will sweep the transducer’s available
frequency range in each ping.
• High Chirp — CHIRP mode (e.g. 130 to 210 kHz)
— No fine-tuning is not needed as the CHIRP
sonar module will sweep the transducer’s available
frequency range in each ping.
With the CHIRP sonar module set to a non-CHIRP
mode the frequency can be fine tuned to adjust the
frequency at which the transducer is transmitting.
The graph below depicts fine-tuning of a CHIRP
broadband sonar frequency (from —50% to +50%).
Low High
S
e
n
s
it
iv
it
y
(d
B
)
Frequency
D12575-2
3
-50%
+50%
1 2
1. Tuning range
2. Transducer characteristics
3. Operating (center) frequency
Fine-tuning the sonar frequency
When connected to a Traditional or Legacy sonar
module or when operating a CHIRP sonar module
in non-CHIRP mode the transmit frequency can be
fine-tuned.
From the Fishfinder application:
1. Ensure that the channel frequency that you want
to fine-tune is displayed in the active Fishfinder
pane.
2. Select Menu .
3. Select Set-up .
4. Select Sounder Set-up .
5. Select Tune Frequency .
The frequency adjust control is displayed.
6. Adjust the frequency until optimum results are
achieved.
Fishfinder application
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