First sonar.. Problems and dumb questions

[JRammit]

So I just got my first sonar for my birthday.. A little Lowrance 3dsi elite, for my little 12 ft Jon boat.... I've taken it out twice now and haven't caught anything.. Maybe because I spend more time staring at the screen than casting, or maybe it's the weather.. Who knows... I thought fishing was supposed  be easier with these things, but apparently there is a learning curve, who woulda thought 

 

Anyway, I'll start with the problem... Most of the time it works fine, but occasionally it will randomly start several new screens.. Sometimes just 2 or 3, other times it looks like you let a toddler play with your computer and he opened every window you have..... I'll try to post a pic here, see how this new format works

Well, it's a little sideways, but you get the idea.... Why would it do this??

 

Now the dumb questions... I've never used one of these before, so here's all I know so far..... The right of the screen shows what's directly under the transducer, the left shows what I've already passed.. And white dots are theoretically fish..... That's it

 

I mounted the transducer to my trolling motor, so what happens when I turn it??.. What am I looking at then??..... Keeping a little aluminum boat steady in the wind takes a lot of steering, if I'm constantly spinning the transducer around, does it get dizzy?

And how wide is the cone?... If I see a tree, is it right under me, or could it be a few feet right or left??.... I made some makeshift marker bouys, how do I know which way to throw them to avoid dropping them into the cover?

And if fish are dots, then what is a line? I see lines sometimes, big thick lines and long skinny lines... Sharks?

 

That's all I can think of at the moment, any other tips or tricks would be appreciated!... I've done well pounding the banks for years, but I know there's fish off shore too, and I wanna find em!

[Josh Buck]

I am no expert and have never used a Lowrance, but I'll try to answer your questions as correctly as I can.

The new screen problem may be a problem with the battery. My Humminbird completely freezes if the battery starts to get low. I will assume you have the trolling motor and sonar on the same battery. My suggestion would be to upgrade the battery or get an extra for the sonar.

The white dots are theoretically fish, but could be leaves, or turbulence in the water.

From the description I read on Cabelas on your sonar it is a dual frequency, with my sonar I can use either frequency or both at the same time. The size of the cone is relative on how deep the water is (shallower water = smaller coverage.) I think my sonar has a 30 degree cone and a 60 degree cone. On the regular sonar screen I can tell which beam is picking up the object in the water by the color of the object on the screen (red is the narrower beam, and yellow is the broader beam.) I can only guess about the location of the structure (I hardly ever use the down imaging alone, usually paired with regular sonar or sidescan), but I will try to attach a photo on what I think. 

If you see a tree on your screen, chances are you passed right over it or just next to it. Best way to find the tree again would be to throw your buoy, then turn around and scan next to your buoy and see if you still find the tree. Or toss your buoy and fish something weedless around it until you hit structure, then fish the lure you are wanting to try.

With the down imaging, I don't think that the rotation of the trolling motor would have much affect on the image. Side imaging will be skewed with rotation of the boat or transducer

A round cloud looking object is usually a ball of bait fish. Longer or thicker lines or bars could be fish, but could also be a limb with few or no branches, or if fishing around docks or marinas it could be the anchor cable.

The other main thing is to just get used to the thing by using it. I have had my sonar for almost 6 years and it is now outdated (Humminbird 798) and I am still learning how to use it. The user manual is boring and sometimes difficult for me to understand, but it will help to look it over.

Hope this helps some.

[JRammit]

Yes that helps!... Thanks for the reply!!

You are correct, I have one battery in the boat... But it's fairly new, and fully charged every time I go out (learned to do that the hard way after paddling to shore against 20 mph winds one day)..... If I were to get another battery for the sonar, would something smaller work?.. Like a lawn mower battery??..... Not only for cost reasons, but weight issues as well (small boat)

The lines I see are out in open water.. I've also seen thick clusters of white dots, which I assume are schools of baitfish.. So the lines threw me off... They were off the bottom, so likely not logs

And you confirmed my theory about structure proximity... Few times I did what you suggested, drop the bouy and go back... My bouy was anywhere from 5' to 20' away from the structure.... Now I understand why, that structure could have been at any point of the cone

This thing is more complicated than I thought... But it sure beats dragging my anchor around to find creek channels!

[JRammit]

 

Hey, I just found this sitting in a corner of the house, didn't even know I had it

Came out of an old power wheels car my kid had about 5 years ago... Don't know if it's still good, I'll hook it to my charger after work and find out..... If so, this'll work right?.. Says 12 volt on it

[Braided Line]

If it were me ,  I`d call the manufacture .    I`m sure they have tech help.

 

Customer service   1-800-628-4487   

Edited December 6, 2016 by Braided Line

[Josh Buck]

No problem. Another thing I have noticed with sidescan possibly down scan also, the speed can affect the quality of the image. I think my optimum speed is between 2 and 6 mph. If you are barely moving or sitting still and fishing, a leaf could theoretically make a bar if it stays in the cone too long. If your unit has the capability, after you have found structure and are fishing around it I would switch back to a regular sonar screen.

I am afraid to say to use a lawn mower battery. As long as it is 12 volt it would work, but probably not for very long times. First I would try turning down the brightness level as much as possible, as long as you can see the screen.

I am using a 27 group deep cycle for my starting battery and sonar battery, but it is on its last leg. I have to turn the brightness down until I can just barely see the screen, and then it still will draw too much out of the battery and make it go haywire. I still have more than enough juice to crank the big motor, and that is what I have to do. Start it up and let it idle for 30 seconds or so, turn on the sonar and change the brightness level quickly. It's not annoying enough to get a new battery yet, but it will blind you at night. I think I am about to switch it from the cranking battery over to one of my trolling motor batteries.

Just hang with it and you will soon be finding stumps, big rocks, bridges, roadways, foundations, creek channels, etc. Anything to keep from draggin that anchor.

[Josh Buck]

Since you already have it, I would try it. But I think that battery, even if it were brand new, wouldn't last the whole trip. But I have been wrong a time or two.

[JRammit]

I'll call the manufacturer when I get a chance, thanks for that number braid

Josh, speed isn't much of an issue with my little Minn Kota, but I see what you're saying about an object staying in the cone

Another dumb question.. Looking at the picture you labeled for me, you have the far right labeled "farther from the transducer" and just to the left labeled "directly underneath"....... So, is it scanning ahead? Like the far right is just in front of me??.... Or is it scanning the cone side to side? Like the far right is just to one side of me??

[JRammit]

8 minutes ago, JRammit said:

Another dumb question.. Looking at the picture you labeled for me, you have the far right labeled "farther from the transducer" and just to the left labeled "directly underneath"....... So, is it scanning ahead? Like the far right is just in front of me??.... Or is it scanning the cone side to side? Like the far right is just to one side of me??

 

Wait, I think I got it... This thing is 3D right?.... So that's why the bottom shows up as a wide image.... Your arrows are indicating top and bottom of the image, not left and right........ So the lower portion of the image is behind the transducer, and the upper portion is right under 

that changes things... I really didn't know what I was looking at before.... Can't wait for my next day off now!

[Josh Buck]

That is how I read mine, but I may be wrong.   Sorry if I am starting to confuse you, I am starting to confuse myself haha. Also youtube has tons of videos on how to read down imaging and so on. https://www.youtube.com/watch?v=iG8HkZIB2Eo This guy covers down imaging starting around 3 minutes in.

Edited December 6, 2016 by Josh Buck

[JRammit]

It's hard to find any informative videos on the cheaper units like mine... Most of the videos out there cater to the high end units

I watched yours then swiped around for a while and found this short one... Gives me a good picture of what I'm looking at

 

 

Makes me wonder, can I judge the location of structure by the resolution?..... If it's in the center of the beam, the image should be clearer right??

Edited December 6, 2016 by JRammit

[Josh Buck]

I don't know if you could determine the location based on that. The more I look into it, I think I was wrong in the picture I posted. I think that may just be showing a relatively hard bottom, that's what it would look like on regular sonar.

If the info on Cabelas is correct and I did the math correctly, then when using the 455hz setting, the amount of bottom scanned is approximately equal to the depth, and the 800hz setting is approximately half the depth.

So in 20ft of water the 455 hz is scanning roughly 20ft of bottom, so a stump would be within 10ft of either side of your boat. 800 hz would be about 10ft of bottom, 5ft either side of boat.

[BobP]

You don't want to connect your sonar to the same battery as your trolling motor because the motor will cause electrical interference whenever you turn it on.  This shows on the screen as vertical lines.  There is a lot of  information on a sonar screen if you learn how to interpret it and like anything, it's a learning curve you have to climb to get the most out of it.  How to set up the sonar to give you the best information?  What do bait fish look like?  What do large fish like bass look like?  What bottom structure is conducive to bass habitat?  What does a thermocline look like and how does it affect fishing?  The best advice I can give is to get on YouTube and see some of the screen interpretations from experienced users.  Then get out on the water and see how your sonar pics compare.

I use sonar differently according to the season.  In warm water periods, it's mostly to find the best bottom structure to fish, to find how deep the thermocline is, and to note the presence of scattered bait fish.  In winter, it's to find schools of bait fish and see if they have active bass around them.  I don't fish offshore unless and until my sonar tells me the bass are there.  It eliminates the unproductive water and sometimes points you to a surefire bite.  

[JRammit]

Thanks Bob

When I say "offshore" I just mean not on the shore... The shore line has been all I could see until now... The lakes I fish are small (30-40 acres) so I run out of shore line fast

Ill mainly be looking for submerged duck blinds that were built when the water was low.... There's on in particular that was made from a layed over tree, at least 20 ft long and about 20 feet from the main creek channel..... I have no idea how deep it sits now cause I haven't been able to find it by dragging a Texas rig... It's the 20' needle in a 30 acre hay stack..... But now I have my needle detector!

So it's unanimous that I need another battery... I'll make due with the malfunction til after the holidays, then get me a battery... Hopefully that will be the ticket, luckily it does work currently, just a little annoying with the screen problem

Thanks for all the help!... Maybe just one more dumb question..... A hard bottom shows up brighter right? And a soft bottom would show up kinda dull??

[BobP]

http://www.scout.com/outdoors/wired2fish/story/1467188-how-to-use-sonar-to-find-hard-bottoms

rock transmits sonar better than mud so it should show up thicker and yellow on your color sonar.  If I had one sonar on a boat, I would mount it on the transom and have the display on my console.  That way, you can cover water faster from the comfort of your seat, and at higher speed.  See something?  Toss a marker buoy out the rear of the boat.  I'm betting that once you get used to it, another sonar for the bow will soon follow.  I use my trolling motor unit too, but turn it off when I get shallow and stop the boat to fish so as not to spook the bass (and run my TM at low speed for the same reason). 

[JRammit]

One of these days I'll have a boat fancy enough for two sonars, but this is what I'm working with now... And the reason I only fish smaller waters

The display is mounted on the small front shelf, so it's right in front of my face..... Transom mount wasn't an option cause the boat rides in the back of my truck, so there's always some dragging and sliding involved when loading/unloading..... So it's on my trolling motor, which gets dismounted when the boat leaves the water

I'll check that link out now, thanks again!

 

[mjs]

DSI, if I'm reporting what I've read right, isn't a cone. It shows a realistic picture because it is a 2d to 2d. Just the orange beam in your picture above. Not the best for marking fish, but better to see what kind of cover your looking at. Like you said seeing your depth is the most important thing. Long lines are caused by whatever it is, fish maybe, staying under the cone a long time. When it moves in and out you get the white blob. 

[stretcher66]

for a 2nd battery for the sonar , look into electric wheelchair batteries.  small but light and they are deep cycle.

 

https://www.walmart.com/ip/PowerStar-PS12-18-94-12V-18Ah-CB19-12-Sealed-AGM-Rechargeable-Deep-Cycle-Battery-2-Years-Warranty/183347885#about-item

[Musky Glenn]

I believe a lot of your problem is in the mounting of the transducer on the trolling motor. When you turn your trolling motor the screen should change as well. As you said it probably is getting dizzy. I would rig up a quick disconnect and mount it to the back of the boat so that it will always be in line with the direction of the boat. Then, what looks to the right will really be to the right. You can still mount the screen on the front of the boat. The screen shot shows 10 + volts, that is a near dead battery. My motor will start at a lower voltage than the depth finder will operate at. Good luck.

[BobP]

I can see bottom features and mark fish at 50 mph with my H’bird SI capable 987 sonar in downscan mode.  But the SI feature will only give an intelligible reading at speeds below 10 mph and is useless attached to a trolling motor unless you choose a direction and keep the TM stable.  The SI takes small slices to the side of the boat and it takes a bunch of them to build up a useable picture.  Turn the TM and the pic is a useless jumble.  That’s why it’s advisable to mount a SI sonar on the transom.  You can creep along a shoreline with the motor and study the underwater  cover.  You can motor at higher speeds over deeper water and detect cover, bait schools, and bass with the downscan feature.  I have sonars on both the transom and TM on my boat.  I use the transom unit 90% of the time.  I often fish with both sonars turned off because I already know from the Transom unit if there are fish present and I don’t want a sonar’s sound to alert nearby bass.  My main use of the TM unit is in winter when jigging for deep bass over shad schools.

Edited April 29, 2018 by BobP