What am I seeing on my HDS7?

[311Hemi]

Can someone tell me what I am seeing on my HDS7, referring to the sonar side?

1) In this pic I would see these lines go at an angle from near the bottom up to like 15ft or more. I was on a mud flat in the middle of Mille Lacs.

2 & 3) The screen would become fairly cluttered like this when I accelerate, and it really does not seem to get much better from there. Here I am going 4 mph. Is this normal or do you guys get good pictures when moving any fast than trolling? I am in auto mode. If I go to manual and degrease sensitivity I can get the clutter to go away some.

3) High speed shot with sensitivity turned down so the image is not so cluttered. Should I be able to get a better image than this when doing 30mph? On auto the screen is full of clutter.

[Nick Kuhn]

If adjusting the settings doesn't do anything you are likely seeing either interference or cavitation. The causes would be mounting multiple transducers too close together, mounting too close to a propeller, or not mounting low enough on the transom.

Otherwise the unit may just be defective. You should definitely be getting better images than that regardless of the speed you are traveling.

[Surface Tension]

I'd go manual and turn the gain down more to start with. Auto should do a better job then this, for that reason I'd check ducer alignment and placement.

[311Hemi]

How about the first pic, what would be causing that line?

[MJCatfish]

Was there a mayfly or other fishfly hatch going on?

MJ

[Surface Tension]

How about the first pic, what would be causing that line?

Suspended fish.

At .5 for speed it is common for targets to mark as lines. It is just a matter of how long the ducer was over the fish + cone angle.

[311Hemi]

Suspended fish.

At .5 for speed it is common for targets to mark as lines. It is just a matter of how long the ducer was over the fish + cone angle.

I can and do see lines going across the screen horizontally which would be suspended fish, but the lines in the first pic would actually go from near bottom then raise up 10-15' in the water column with no breaks in the line. I captured a bad pic and it does not show as extreme as most of the ones I was seeing.

I didn't see much for bugs on the surface, but there were some mayflies in the boat.

The transducer is only 12-13" away from the motor mounting bracket. Maybe I should try moving it away some more? The transducer is mounted lower that what the manual calls for, that being the mid-line of the ducer even with the bottom of the boat, could that be an issue?

[Dale Rueber]

How about the first pic, what would be causing that line?

Do you have 2 sonars running or are you near any other boats when you see the lines running from the bottom at an angle? I would see these lines only when I was running both depth finders and was in more than 20 FOW or if I was near another boat. In my case this was cross-talk between the 2 units and I believe was caused when the 2 units ping synched up.

As far as your transducer goes, the location looks fine but you may want to try moving it right or left. Is there anything that ahead of the transducer that might cause a lot of air bubbles? I get a lot better picture at high speeds that you are getting but I also have the Structure Scan connected so it is not a direct comparison.

Also I had an issue with a lot of clutter and not being able to see the bottom well after I had changed one of the settings. I can't remember exactly but I remember setting it to Freshwater caused the poor performance. Changed it back to Normal or whatever it was from the factory and it worked much better. I believe there is a way to change all of the settings back to factory.

One more thing, make sure you have selected your transducer type in the settings.

[Surface Tension]

I can't tell from the pic but will say that the bottom of the ducer should be parallel to the transom.

Yes it looks too low to me.

You might be a little close to the outboard but at slow speeds or when using a trolling motor it wouldn't matter so I don't think that is the problem. If you move to far away from the outboard you stand a chance of the ducer losing contact as the boats hull planes out.

That type of a mount will have a tendency for the ducer to tip up. The outside/back edge should tip down a hair. All the above would be best for high speed performance.

Nothing there that I see would indicate a problem at slow speeds. I still think the sensitivity is too high as the readout looks hot to me. The line from bottom to top could be a change in water temp. Note how hot that line is marked.

So I'll say lift the ducer up.

Keep it parallel to the transom

Tip the the backside down a hair from being flat with hull.

Turn the gain down.

[311Hemi]

FF, there were times that we were in close range to another boat, maybe 20-30 yards. Never even thought about their sonar, I guess I will have to pay more attention to that if I see it again. I am only running the one sonar.

There is nothing in front of the transducer there that I am aware of. I cut the transducer board at an angle and mounted it 1/4" up, so that is not hanging below the bottom of the boat. Not sure if that 1/4" would cause any issues.

I am running the latest software and had it set to shallow water mode. I also have the correct transducer selected. That was all set up before I updated the software so maybe I should double check to make sure it's still set correct after the update.

[PerchJerker]

Does your HDS-7 do this on other lakes, or just on Mille Lacs? Mille Lacs has tons of bug hatches that can really clutter a screen. If you're not seeing it on other lakes then I'd lean to blaming the bugs in the photos you posted.

You might want to tweak some settings on your unit and see what that does for you. One is the noise rejection level, try it on Low, Med or High and see if that makes a difference. You may also want to increase your surface clarity rejection setting. I also think you might be getting some electrical interference and may need to rearrange your power wires a bit to clean it up, but I'd try the other settings first.

Also, it looks like you have your colorline setting way too high, unless you're over a super super hard bottom.

[Whoaru99]

Diagonal lines a couple of fish rising in the water column, coupled with the low speed? Just a wild-a$$ guess...

[solbes]

I haven't seen anything like that on mine. But I rarely use the zoom feature. Is that on 4x? Maybe that's what looks so strange to me.

I would say at 0.5, the first picture is plausable if large fish are moving up or down near the bottom.

2 and 3 look like the sensitivity is too high. I agree with PJ, try increasing your noise rejection up one level and see if that helps. It not, adjust your sensitivity down. I've had mine ramp it up and down way too far in auto mode.

4 doesn't look too bad if you are moving at 30 mph. Maybe because your transducer is a little low you're getting some kind of cavitation aroud it? Mine is a bit higher and I usually get pretty good results. The angle of the transducer front and back made a big difference for me also. Have you seen it mark any arches yet? If not I'd try moving it up some and adjusting the angle.

[311Hemi]

Thanks guys....your giving me some good ideas to look into.

Quote:

Also, it looks like you have your colorline setting way too high, unless you're over a super super hard bottom.

I was on top of a mud flat and this was the auto setting. I will have to pay more attention on other lakes regarding the bugs, but if your refering to pic 2 & 3 they looked good at idle/trolling speed. It does this when moving faster than trolling speed.

I haven't seen anything like that on mine. But I rarely use the zoom feature. Is that on 4x? Maybe that's what looks so strange to me.

I would say at 0.5, the first picture is plausable if large fish are moving up or down near the bottom.

2 and 3 look like the sensitivity is too high. I agree with PJ, try increasing your noise rejection up one level and see if that helps. It not, adjust your sensitivity down. I've had mine ramp it up and down way too far in auto mode.

4 doesn't look too bad if you are moving at 30 mph. Maybe because your transducer is a little low you're getting some kind of cavitation aroud it? Mine is a bit higher and I usually get pretty good results. The angle of the transducer front and back made a big difference for me also. Have you seen it mark any arches yet? If not I'd try moving it up some and adjusting the angle.

Yea, it was on 4x in that pic. The lines in the first pic would move up from 25' to about 10-15', so these fish would have been coming up a ways off the bottom if that's what it was. I think interference from another unit could be one explanation as someone else mentioned.

2 & 3 looked good at idle, it didn't look like this until I gave it a little throttle and the boat started moving. I think I need to play with the transducer location a little to see if that helps.

I will also have to rev the engine to see if I get interference from that, when not moving.

[solbes]

I've seen some weird things on auto mode too, although different from what you've shown. Sometimes it ramps up the colorline until even soft bottoms are yellow. And other times it will ramp up the sensitivity until the screen is filled. Good justification for me using manual mode all the time. I don't mind adjusting the sensitivity up and down a few clicks every once in awhile.

I would try moving your transducer and see if that helps. If not run it in manual mode for awhile.

[Ed Carlson]

Turn surface clutter on.

Set sensitivity to auto or mid point.

Set scroll rate to max, or auto....try max.

Reduce color line setting.

(Or...go to system settings, and do the system reset to factory new settings and then tun on the surface clutter reduction."

Diagonal streaks on the graph could be active fish being graphed at a slow chart speed and slow ping rate, or lures being tracked on the bottom, and/or sonar targets like weeds being read at a very slow chart scroll rate...or possibly cross talk interference from your boat or another boat near?

If I may recomend a new tool out that will help a lot with your HDS, I recommend you pick up Doc Sampsons new DVD on the HDS system and how to fine tune it. Great DVD, and it is very well done and informative. Lots of great tips in there to get the most out of your unit and you get to see it and all the settings and adjustment tricks live on the DVD...very handy tool.

[Turkeynate1]

First pic is in fact a bug hatch. I fished with a guide this past week and asked the same question about his graph because I get the same thing on my HDS 8. He said it's showing the bug hatch. My Verado has a little interference after running at 10 mph then moving it into just gear. There is a 10 sec moment of interference then it clears up. After it clears up you can bump up your speed a little and still get good returns at that point. The unit it working just fine. The other thing the guide said to do was turn on the surface clutter feature like previously mentioned. I'll see if I can pull some pics from some recodings I did this past week.