Reading Sonar Correctly for Vertical Fishing
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Reading Sonar Correctly for Vertical Fishing

January 16, 2020

This is a great example of arches. These
fish were in my cone angle and now they’re gone. If those fish were still in here under my cone angle under the boat there will
be a solid line. Now the neat thing about the lines that will go up and down you
can tell those fish are there but it’ll still be in the screen. Right now there
are no fish down there. If I take my bait and I drop it down we’re gonna watch…my
bait go down…okay so that’s me – that line. A line means that it’s in under the boat.
That signal is still there. If I raise it up it comes up. If I lower it it goes
down. That means that I am still there – I’m in that signal. If there’s a fish
there he’s going to show up as a line so I can watch the two lines meet. If
there’s a fish down there I drop my line to meet the other line which is the fish.
That’s the difference. Arches mean they have come and gone. A line means is that
fish is still there. So a big key when fishing vertical is knowing the
difference of arches and lines. You want to see lines – that means they’re still
there. Let me see if I can get one to come in the screen here this top line is
me. Okay so I have a fish coming up to look at me right now. That’s him on the
bottom that’s me on the top. He’s still there looking at it. Another one’s coming
up to it….I got him! [laughs] It’s cheating! I’m telling you! [laughs] It’s a nice one too! Okay so what people don’t realize is the
difference between an arch and the line A line on the graph means that signal –
that interference – that thing that’s between bottom and boat is still there.
It’s showing that target still there. An arch means that the target has come and gone is no longer in the cone angle. The cone angle is a signal sent from transducer to the bottom, bounces off the bottom comes back up and then reads it
on the screen. So the line means that when it bounces down, it sees it. When it goes down it sees it, when it bounces up it sees it. It’s continuing to
see this fish or my bait down there. A line is going to tell you that that fish
is directly under the boat.


  • Reply Jeff Dunn December 26, 2017 at 6:50 pm

    My hummingbird helix won't show my lure, i even tried using my anchor and still don't get it to show anything. So how is it supposed to show a fish if it won't even pick up a 20 pound anchor. Ive spent day's trying to figure it out.

  • Reply Bob Askey December 26, 2017 at 9:13 pm

    Great video. Have heard of guides here in Oregon salmon or Steelhead fishing and tell the client a fish is going for your bait or lure. Also guides, the really great ones, are using side image to locate salmon and Steelhead especially in the rivers. Show we watch mentioned guide Brandon Glass fishing for Winter Steelhead using side imaging and notices fish on the opposite side of the river. Tells clients to reel in moves to the other side and hooks a fish. This spring I am looking forward to having great side imaging to troll for Spring Chinook. They can be in 10' water one day and 30' the next. With good side imaging I hope to locate where the Chinook are traveling and move in that path.

  • Reply BassGeek December 28, 2017 at 2:50 am

    I use my Humminbirds to fish vertical all the time. You guys should show a brother some love. My birds get a lot of Youtube screen time.

  • Reply James Hall fishing March 23, 2018 at 2:20 am


  • Reply Pits McGoo April 30, 2018 at 11:26 pm

    Good video I was always looking for arches. Now I know what to look for Thanks.

  • Reply Republic Gamer35 May 13, 2018 at 2:22 am

    what king of setting on the sonar we should set to get this details. thanks

  • Reply Raymond Vs Bass May 13, 2018 at 4:19 am

    Great video ! Thank you !!

  • Reply South ga jeeepers June 14, 2018 at 10:36 pm

    Wow. This just makes sense now. Been fishing for 10 years with fish finders and had no idea what I was seeing. I only used for depth and water temp. Thanks. This helped me a lot

  • Reply John Redmond November 4, 2018 at 7:32 pm

    Please stop the background music.ย  No one wants to hear it.ย  And it drowns out Brent's instructions.ย  Thank you.

  • Reply afghan bassin November 26, 2018 at 3:39 am

    Great video.
    All you said is true but only when your boat is anchored/not moving. If the boat is moving then you won't see any lines on the Screen but only arches. Unless the fish move with you at your boat speed and direction lol
    Thanks for sharing this video.

  • Reply charles jones January 13, 2019 at 4:29 am

    Good explanation.

  • Reply OhSnapsItsPaul February 14, 2019 at 7:54 pm

    Cool technique๐Ÿ‘๐Ÿผ

  • Reply wlacalle August 25, 2019 at 10:52 pm


  • Reply Jeff X October 22, 2019 at 1:02 am

    Thanks so much. I bought my first real fish finder this summer and have been wondering how to decipher what the screen is telling me. Thanks for clearing it up. ๐Ÿ‘๐Ÿป

  • Reply missile150 November 29, 2019 at 3:32 am

    Just learned the difference between an arch and a line. Awesome!

  • Reply T.H. Dalton December 9, 2019 at 8:39 pm

    Simple explain good job

  • Reply C C December 25, 2019 at 3:16 am


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