28502
37
Zoom out
Zoom in
Previous page
1/88
Next page
TRACKFISH 6500 Installation and Operation Manual 37
NAVMAN
8-4 Fish detection and display
Where to find fish
Underwater features like reefs, wrecks and
rocky outcrops attract fish. Use the 50 kHz or
50/200 kHz frequency display to find these
features, then look for fish by passing over the
feature slowly several times using the Zoom
display (see section 9-2). If there is a current,
the fish will often be found downstream of the
feature.
When fishing with the TRACKFISH with the
Fish symbols Off, a weak fuzzy band may
appear between the bottom trace and surface.
This might indicate a thermocline - a rapid
change in water temperature, such as the edge
of a warm or cold current. The temperature
difference can form a barrier which the fish
may not swim through. In fresh water, fish
often collect around a thermocline.
Fish symbols
The TRACKFISH uses NAVMAN’s SBN
technology to analyse sonar echoes and
identify which are likely to be fish. The
TRACKFISH can be set up to display a fish
symbol and the depth over these echoes (see
section 17-3, Fish symbols). While SBN is very
sophisticated it is not foolproof - there will be
times when the TRACKFISH will not be able
to differentiate between fish and large air
bubbles or rubbish.
Depending on the strength of a fish signal,
the TRACKFISH can display a small, medium or
large symbol (see section 17-3, Fish filter).
To see the maximum amount of information
from the echoes, turn Fish symbols off. Fish
appear as arches on the display.
Fish arches
In good conditions, a fish passing through the
cone-shaped ultrasonic pulse is displayed as
a fish arch. The 50 kHz frequency uses a wider
cone than the 200 kHz frequency. This makes
the fish arches easier to see.
A fish arch starts when a fish enters the weak
edge of the sonar cone, generating a weak
echo that is displayed as the start of the fish
arch. As the fish moves closer to the middle of
the cone, the distance between the transducer
and the fish reduces and the echo is displayed
at progressively shallower depths, producing
a rising shape. When the fish passes directly
beneath the middle of the cone, the echo
becomes strongest and thickest. As the fish
passes out of the middle of the cone the
reverse happens with a progressively weaker
and deeper echo.
There are many reasons why fish arches may
not be seen. For example:
Poor transducer installation (see Transom
Transducers Installation Guide).
If the boat is anchored then fish will tend
to show on the display as horizontal lines
as they swim into and out of the transducer
sonar beam. Slow speeds in deeper water
give the best fish arch returns.
Range is important. It will be much easier
to see fish arches when using zoom mode
to concentrate on a particular section
of water, rather than just displaying
everything from the surface to the bottom.
Zooming increases screen resolution and is
necessary for good fish arches.
It is difficult to get fish arches in shallow
water as the transducer sonar beam is very
narrow near the surface and fish do not stay
within the beam long enough to display an
arch. Several fish in shallow water tend to
display as randomly stacked areas of colour.
Wave motion may result in distorted fish
arches.
Fun fish symbol Normal fish symbol Fun symbol + depth Fish arch
37


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Navman TRACKFISH_6500 at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Navman TRACKFISH_6500 in the language / languages: English as an attachment in your email.

The manual is 2,78 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

Others manual(s) of Navman TRACKFISH_6500

Navman TRACKFISH_6500 User Manual - German - 88 pages

Navman TRACKFISH_6500 User Manual - Dutch - 88 pages

Navman TRACKFISH_6500 User Manual - French - 89 pages

Navman TRACKFISH_6500 User Manual - Italian - 90 pages

Navman TRACKFISH_6500 User Manual - Swedish - 87 pages

Navman TRACKFISH_6500 User Manual - Spanish - 91 pages


The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info