Raymarine A65, Инструкция по установке и эксплуатации

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15.9 Dual / Single frequency fishfinder
Dual frequency operation allows the sonar to operate and display 2
frequencies simultaneously. If the preset mode that you are using
has two frequencies configured, you can view either one or both of
those frequencies in separate windows.
Selecting dual frequency view
From the fishfinder application:
1. Select Menu .
2. Select Presets .
3. Select Dual .
The main fishfinder menu is displayed.
4. Select View Freq .
5. Select the required setting:
• Frequency 1
• Frequency 2
• Both
15.10 Non-CHIRP (traditional) sonar
module frequency controls
The frequency of the sonar determines the width of the sonar beam,
the depth to which the signals will penetrate and the resolution of
the image.
The frequencies supported depend upon the sonar module and
transducer in use on your system.
• Auto . When operating in automatic the system will set and
the frequency automatically to suit your transducer operating
conditions.
• Lower frequencies (e.g. 50 kHz) produce a wide sonar beam
and penetrate the water well. Lower frequencies provide a lower
resolution image that may not be as good at detecting small fish.
Use lower frequencies if you require a large coverage beneath
your vessel or if you are in deep water.
• Higher frequencies (e.g. 200 kHz) produce narrow beam
and produce a high resolution image. They are most useful in
shallower water (up to 1000 ft) and at higher speeds.
The non-CHIRP sonar module will only operate at specific
frequencies defined by the connected transducer (e.g. 50 kHz or
200 kHz).
Setting the fishfinder frequency (non-CHIRP
sonar module)
With the Frequency settings menu options you can configure
frequency 1 or frequency 2 .
1. From the fishfinder application select Menu .
2. Select Frequency settings .
3. Select Freq 1 or Freq 2 as required.
4. Select the required frequency:
Example of Frequency setting menu when connected to a
non-CHIRP sonar module.
Frequency tuning (non-CHIRP sonar module)
When connected to a non-CHIRP transducer there will be an
optimum frequency for the maximum sensitivity of the transducer.
The sonar module can be fine tuned to this frequency.
Non-CHIRP sonar module frequency
1 20 130 140 150 160 170 180 190 200 210 220
S
en
si
ti
v
it
y
(d
B
)
Frequency
-50% +50%
3
2
1
D12574-1
1. Tuning range.
2. Transducer characteristics.
3. Operating frequency.
Using the fishfinder
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