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Side Scanning Sonor/Fish Finder
So I have a technical question about side scanning sonar/fish finders, I troll for trout and koks that early in the year are close to the surface and move deeper later in the year. As you troll along, the fish move around away from the boat. How does the beam on the new fish finders work? Does it go 180 Deg with the boat (like Humminbirds video) or do they have angle towards the bottom. Logic tells me they are angled towards the bottom but that is why I am asking.
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Re: [RJD007] Side Scanning Sonor/Fish Finder In reply to
The side scan on fish finders that have that option are able to look out up to 150 ft straight off to either side of the boat but are able to go all the way to the bottom because there is something to bounce off, before the signal returns to the finder. Since there is nothing for the side imagining to bounce off of, except fish, the max range on a finder is 150 ft.


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Re: [wiperhunter2] Side Scanning Sonor/Fish Finder In reply to
Digging a little deep on this, I sent Humminbird the following questions:

Pre Sales Question

I want to use the Helix 9 mega to side find fish while trolling. All the video's I have seen only shows bottoms. I am more interested in finding suspended fish at what depth and distance from the boat. Do you have any videos that show that? Can the mega do that? I mostly troll for trout and want to use the Helix to know how far out from the boat are the fish and how deep.

Also is the 360 a mega chirp?


This was their response:

Thank you for contacting Humminbird Customer Service.

No it does not show that and we do not have any videos nor do we produce videos for that. As far as the Mega it can only show Mega imaging for up to 45 feet deep after that it changes to HD. The 360 imaging is not Mega based only chirp as the 360 is a transducer on its own it can not produce mega imaging .

So, since I am not a bass fisherman, can someone explain what good is the SI other than to look at a more detailed bottom? I understand structure and how they hold fish, but if I pay that much for a fish finder, I would hope it would show fish also. Do any of the other manufactures support side finding of suspended fish?
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Re: [RJD007] Side Scanning Sonor/Fish Finder In reply to

I have the Lowrance HDS linked sonars on my boat and I have no problem seeing shallow water suspended Kokanees that are out over deep water. Typically if the Kokes are shallow Iím fishing with planer boards and snap weights no further than 30-40 feet off the side. I sent my SI at the 50í-75Ē scale and see everything in my planer boardís path. If you set the scale at say a 100í the resolution is so diminished that you canít see much of anything. Shorten your scale and you should be good to go.



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Re: [RJD007] Side Scanning Sonor/Fish Finder In reply to
RJD007 wrote:
So, since I am not a bass fisherman, can someone explain what good is the SI other than to look at a more detailed bottom? I understand structure and how they hold fish, but if I pay that much for a fish finder, I would hope it would show fish also. Do any of the other manufactures support side finding of suspended fish?

I've used side scan for years and they do show fish, not sure what that guy from Humminbird was talking about but here is something I read in In-Fisherman magazine. This first part is talking about using "Garmin's Panoptix and Live Vu forward, to scan for fish in front of the boat. By turning the trolling motor left and right you can scan along structure or drop-offs and see individual fish. The screen tells you exactly how far they are from the boat and their position relative to the bottom.
This part is about using Raymarine sonar units, with clearpulse chirp transducer, they are available with dragonfly, A-, E-, and Axiom series products. They have an optimized 25-degree-angle transducer that sends out modulating chrip signal operating on 60 different frequencies from 170 to 230 kHz, the results are a huge boost in sonar returns, resolution, and superior target separation."

Not sure what these units cost but this is something new and it is a huge step forward in fish finders.


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