Problem with Structure scan; cannot find solution

Had the Structure Scan installed by marine shop. Everything looks correct.

I have the Structure Scan set for “automatic”. When in this mode it is hit or miss. Sometimes it reads correctly (image and digital depth) and sometimes it reverts to 15′.

Seems like when I motor from point a to point b is when it happens the most. I have to wait for it to automatically change to the depth I am fishing. Sometimes it works correctly; when working right for some reason it reverts to 15′ and I get a super close up image of the bottom. Depth does not seem to matter, it happens at all depths.

I was told by the marine shop to set sensitivity between 90 – 100%. I did this but am still encountering the same issue.

I have installed the most recent update to both units.

Am I the only one who is encountering this problem? If this is not making sense let me know and I will try to explain better.

Which Lowrance unit are you running…HDS?

I am a little confused with your comment from your dealer on sensitivity. The Structure scan only has contrast not sensitivity. It almost sounds like you might need to adjust you transducer for the LSS-1 or maybe your motor is getting in the way of the LSS-1 signal. Does you 2d sonar work OK?

You should start with a contrast setting of around 70% and adjust up or down from there for structure scan and down scan. As said above, there is no sensitivity setting for those. At 90% you are likely not going to be able to pick out much. Can you give a little more detail on what page you have up and what color palette you are running? Do you have it zoomed in?

I have a HDS 5 and 7. Both units are linked. I am using palette #9, blue. I believe i went to the sonar page and into menu to change the sensitivity – it is there, although this did not help with the issue.

Example of the problem: i motor from one spot to other. Upon arrival one of two scenario’s take place. Lss is set to automatic, fishing 35 ft.
1) Lss is working fine, but then out of the blue will change to 15 ft. The digital depth changes to 15 ft., down imaging changes to 5 ft. The image on the screen looks like it is zoomed in, showing such a close up image of the bottom that i change back to the traditional sonar.
2) Lss shows 15 ft, down scan shows 5 ft. Image is zoomed in.

I spoke with Lowrance and he didn’t have too many answers. He told me to trim up the motor as the transducer may be catching the motor, and thinking it is shallow and thus reverting to 15 ft. Have not been on the lake yet to try this.

Lately i have been been using Lss in manual mode, changing the depth setting according to the depth i am fishing. It works, but automatic sure is nice. Using manual mode, i deleted the Lss digital depth reading from the screen and instead added the traditional depth reading.

The traditional sonar works great. No issues at all. Unless there is a setting that i missed, i guess maybe it is picking uo the motor. Perhaps i will need to trim up when i am fishing.

Hard to believe that nobody else has experience this issue.

I am running an 09 Alumacraft Navigator. The Lss transducer is on the starboard side, ~ 10 -12 inches from the traditional transducer.

First item, the sensitivity setting. The sonar menu sensitivity setting is for your traditional 2D sonar. For the structure scan, go to the structure scan menu and select adjust (I think that is the menu item. Its the top one) and adjust the contrast. It plays a similar role to 2D sensitivity settings in adjusting the brightness of your return, making your fish blips brighter or less bright.

With regards to the other problem, I have not seen that one. I don’t typically run the automatic setting as I like to maximize what I see. Coverage is typically three times depth on the side scan. If I’m running in 10 feet of water, I like it set to a range of 30 feet. If I know I’m going to be working 10 to 15 feet, I’ll set it to 40 or 50 feet depending on how the picture looks.

I run an 09 Navigator and my ducers are also on the starboard side, but only 4 inches apart. Just out of curiosity, is your LSS-1 ducer toward the outside or inside of your 2D ducer, and is the 2D lower on the boat than you LSS-1 ducer? It could be possible that your 2D ducer is getting picked up and causing a false return if the 2D ducer is lower.

I do run into issues with my main motor blocking most of the port side view with it trimmed down all the way. When I’m running sidescan, I trim my motor up a ways. I have not seen it freak out on the depth like yours though.

One other thing to check. Make sure your on a structure scan page, and then hit zoom out a few times. I don’t know if when you zoom in it remembers you are zoomed next time you power up, but just make sure you are zoomed out all the way.

John,

Thanks for the input.

Sensitivity… I will turn this back down and use the contrast on the Lss. Out of curiosity, what are you running for sensitivity on the 2D?

Transducer… Looking at the back of the boat, my 2D trans is lower and to the left of the Lss. The Lss is approximately 10″ – 12″ to the outside (NE) of the 2D trans. You would be correct in that the 2D trans could be in the way of the Lss, just as the motor shaft/lower unit also. Perhaps it is picking it up and reverting it back to 15′.

You said that you run in manual mode. Out of curiosity, why are you running it this way and not in automatic? Are you running an HDS 5/7 or 8/10? I could just as easily run in manual mode, just thought it would be easier to run automatic and have the unit do the work whilst I fish/look for fish – haha.

The depth reading, for all practical purposes, has been fixed. Running the digital reading from the 2D trans has not been a problem. My only issue is the image of the SS and Down image.

I think I will try to trim up the motor and see what happens. If this doesn’t work, maybe go back to the marine shop and have them relocate the Lss trans lower and to the inside of the 2d trans?

For the 2D sensitivity, I think I am usually running somewhere around 80%, but I change it quite a bit depending on depth and water clarity. To be honest, I don’t use the 2D for much other than when running on plane or when jigging. I adjust it so I get a fair amount of clutter, but can still see fish easily.

I like to run manual on the sidescan because I find the auto tends to use a bigger range than you can actually cover. For instance, if I’m trolling in 7 to 10 feet of water, the most area you can cover is around 3 X Depth, so 30 feet. If the auto is running at 50, I’m wasting screen on stuff the sonar isn’t getting to. If I’m fishing varying depths, I’ll let it run on auto, but I don’t run auto very often.

I run a 5 in the bow and by the kicker and a 7 at the console.

I would first try trimming your motor up while running side scan and see what that does for you. If that isn’t the answer, I would go back to where you had it installed and have them move the transducers closer together and on more of an even level.

It sounds to me like you are picking up something relatively close to the transducer that is making it think you are in really shallow water. Hopefully its just a setup issue.

If you were closer I would say lets hit the water and play around with it.