Author Topic: 898 side scan false traces (Read 24540 times)

planesmith · « **on:** April 22, 2012, 07:33:15 PM »

New to the forum and just installed an 898c SI. Took it for a test run on the lake and all looks good except the Left side side scan shows some kind of thin false return right next to the boat center line on the display. I lifted the motor to make sure it was not blocking the returns. Made no difference. I then shut the motor off and no change.

I did find that when I increase boat speed to over 5MPH the ghost trace dissappears. As soon as the boat hits less than 5 MPH it comes back. I am wondering if the transducer is pointed too far forward? When the boat speed increases the transducer may tilt a bit back due to the play in the bracket?

Anyone who has seen this symptom let me know. I wish I was smart enough to export a display but just bought the unit and have not figured that part out yet.

sonar2000 · « **Reply #1 on:** April 22, 2012, 07:45:26 PM »

If you got the manual or disk go to the part for snapshots.
If you did not get a manual the forum here has a section for manuals and they all work the same way for snapshot.
There are several postings also to put a snapshot in a post.
Try the search tab at the top of the menue here for your searches.
If you get stuck we can point to several postings that might help.
In your case a picture or two will be worth a thousand words..
Chuck

Humminbird_Greg · « **Reply #2 on:** April 23, 2012, 10:43:53 AM »

planesmith,
Are those thin lines there when the boat is drifting with the motor off and raised out of the way?
Can you post some images of your boat’s transom looking from behind and also from the left and right (at about the same height as the transducer)?
It sounds like there is some sort of physical blockage of the left Si sonar but it could be air mixed water flowing off the hull.
Oh, work on learning how to make a Screen Snapshot.

sonar2000 · « **Reply #3 on:** April 23, 2012, 10:46:59 AM »

Plane, what kind of boat do you have?

Chuck

Moose1am · « **Reply #4 on:** April 24, 2012, 12:22:22 PM »

I have the same thing now. I didn't have it until recently. I think that it's either some electrical interference with the transducer wire or the new software has a bug in it that causes this on some sonar units.

I never had this until this year. I just updated my software to the new 5.7 then the new 6.180 software. So you are not the only one to have this line next to the center line in SI mode. It's on the left side of my screen too. My motor is to the left of my transducer but the motor has never interfered with the SI signal before.

I have to do some more testing but I fear it's my transducer going out. I'd like to get it exchanged to make sure it's ok before my warranty expires. I have the extended warranty still.

[quote
author=planesmith link=topic=3965.msg23849#msg23849 date=1335137595]
New to the forum and just installed an 898c SI. Took it for a test run on the lake and all looks good except the Left side side scan shows some kind of thin false return right next to the boat center line on the display. I lifted the motor to make sure it was not blocking the returns. Made no difference. I then shut the motor off and no change.

I did find that when I increase boat speed to over 5MPH the ghost trace dissappears. As soon as the boat hits less than 5 MPH it comes back. I am wondering if the transducer is pointed too far forward? When the boat speed increases the transducer may tilt a bit back due to the play in the bracket?

Anyone who has seen this symptom let me know. I wish I was smart enough to export a display but just bought the unit and have not figured that part out yet.
[/quote]

Humminbird_Greg · « **Reply #5 on:** April 24, 2012, 01:03:54 PM »

Moose,
Make sure that you went back to using the same menu selections that you had before updating the software. If the menus got reset to the factory settings they could be different than what you were used to.

Same question for you:
Are the thin lines there when everything is shut off and the boat is drifting?

Moose1am · « **Reply #6 on:** April 24, 2012, 01:58:17 PM »

OK I reset my unit to the default settings both before and after installing the new software.
I'll have to get back to you about the drifting. All I know is that my boat is balanced on the water for and aft and from port to starboard and it's level with the water as is the transducer. I've had this transducer metal bracket on my boat since around 1985/86. It came with my Humminbird LCR 8000 unit. The metal part of the bracket has not changed a bit since back then.
I'm wondering if there is some sort of electrical noise coming into the transducer wire or the transducer is bad. I have good laminar water flow around the tranducer. The tranducer is below the water bottom of the boat so it's clear of obstructions. I've tilted my motor up and out of the way and still get that line on the left side. When the weather gets warmer I'll be back out on the water playing with this.
It's either the transducer going bad, electrical noise of some kind that was not there before or the software is buggy. I have a friend that has a similar unit and maybe I can talk him into letting me connect my control head to his boat and check it out using his boat and his tranducer. He can check out my transducer using his control head maybe. But that's a lot of trouble IMHO.

Humminbird_Greg · « **Reply #7 on:** April 24, 2012, 02:45:44 PM »

It may be a lot of trouble Moose but it will be worth it to be able to know where the issue is (transducer or unit).

sonar2000 · « **Reply #8 on:** April 24, 2012, 02:53:18 PM »

Unless you have a lot of complicated wiring and mounting the heads should switch pretty easily.
We carry a couple of extra cables for power, transducer and GPS antenna just for swapping our units for another one in/out for problem determination..

If you have other folks around it may be worth the extra cable cost to help with a problem or fix..

Chuck

yenrec · « **Reply #9 on:** April 26, 2012, 09:57:36 AM »

I was searching this the other day because i noticed it on my brand new unit as well, mine occured mainly at faster speeds, but once again only on the left. I may have found it on humminbirds website that if your unit is hooked up to your starting battery, it may pick up interference from the alternator charging the battery, also they mention switching to resistor spark plugs or something of the such if it has to do with interference under power. Ill see if i cant find the exact link and postt it up.

yenrec · « **Reply #10 on:** April 26, 2012, 10:04:16 AM »

here is the link i was talking about, i hope this helps! http://www.humminbird.com/FAQ.aspx?ContentId=1752

Humminbird_Greg · « **Reply #11 on:** April 26, 2012, 10:48:30 AM »

yenrec,
I think that they are talking more of a constant Si sonar return that only shows up on one side of the Si sonar (see picture below). Typically electrical interference shows up on both sides of the Si sonar (but not always) and also in the 2D sonar.

sonar2000 · « **Reply #12 on:** April 26, 2012, 11:08:37 AM »

the last picture generally indicates a blockage of a signal particullarily near the surface.
dont know if the pic is from your boat or just a reference.

Chuck

Humminbird_Greg · « **Reply #13 on:** April 26, 2012, 11:21:29 AM »

The picture I posted was from one of our test boats. Note that I set the SI Range to the 0 to 20 foot range so that the multiple return lines would be more visible. This is an example of what Si sonar blockage could look like on anyone’s boat.

Moose, planesmith: Is this something like you are both seeing?

yenrec · « **Reply #14 on:** April 26, 2012, 12:16:52 PM »

i had it on my boat last weekend,( only had it out twice since installed), but my lines, only when moving 1/4 throttle on up to full were running from left side SI to the middle line, never came onto the right side.

Humminbird_Greg · « **Reply #15 on:** April 26, 2012, 12:31:02 PM »

yenrec,
Are you talking about main motor interference like the link you posted or are you meaning like the lines in the image I posted?

sonar2000 · « **Reply #16 on:** April 26, 2012, 12:38:35 PM »

It would be really helpful if you can snapshot this occurance and post...

Chuck

Moose1am · « **Reply #17 on:** April 26, 2012, 01:33:50 PM »

Quote from: Humminbird_Greg on April 26, 2012, 10:48:30 AM

yenrec,
I think that they are talking more of a constant Si sonar return that only shows up on one side of the Si sonar (see picture below). Typically electrical interference shows up on both sides of the Si sonar (but not always) and also in the 2D sonar.

Greg: No mine has a single line that run's down the screen parallel to the center line and it's very bright. It's a narrow line and about 5 pixels or so from the center line. And it's on the left side of the center line. Center line is where the path of my boat went.

sonar2000 · « **Reply #18 on:** April 26, 2012, 01:41:19 PM »

Moose1, looks like a hard reflection off of something at the top. I say hard because of the bright color..
Again, a snapshot might help also..
Chuck

Humminbird_Greg · « **Reply #19 on:** April 26, 2012, 01:49:22 PM »

Depending on the SI Range you are using it could like one bright line Moose. Set the SI Range to the 0 to 20 foot scale and you may see multiple weaker looking lines like in the image I posted. Still it could be the same thing causing it – that is a blockage of sort.

sonar2000 · « **Reply #20 on:** April 26, 2012, 01:54:57 PM »

Moose1, yenrec,
could you post a picture of your transducer installed also. From to back and side to side..

chuck

Moose1am · « **Reply #21 on:** April 26, 2012, 02:19:14 PM »

I'll try to get the SDHC chip out of the unit. It's still in my unit which is on the boat. Boat is in the garage and I'll have to move some stuff in order to pull the boat out so that I can get to the card and the unit.
I've finally bought a good dslr so pictures are no problem for me anymore. I'll snap a few for you guys. Actually I probably already have them somewhere on my computer already. I'll have to find them.
Here is the thing! I never had this line before. Nothing on my transducer has changed. I did play around with some of the wiring in the back of the boat where I coiled the excess transducer wire into coils.
If this was bouncing of the motor or anything else on the boat's bottom or left side it would have showed up when I first installed the transducer.
My best guess still is electrical interference of some kind or something gone bad inside the transducer.
It's not stopping me from fishing yet so I'm not that worried about it ...yet. It's more of a inconvient distraction than a big problem to me.

sonar2000 · « **Reply #22 on:** April 26, 2012, 02:37:10 PM »

Moose1 when did you get the system?
there was a post somewhere about a short period of time when the transducer assembly was not quite up to par..
Look on your unit and the serial number will give us the date of mfg.
Greg, could probably check on this with the serial number..

The serial number is date coded.
The first two numbers are the year, the next two are the month and the next two are the day of the month.
As an example: if your serial number was 12010305-0159 then it would have been produced on January 3rd of 2012 .The other numbers represent the test station (05) and the sequential number of the unit that was tested at that station on that day (159th unit tested).

Chuck

arvinc · « **Reply #23 on:** April 26, 2012, 05:13:42 PM »

I have the same line on mine. I have trim tabs and I think the transducer is picking up the left tab.

sonar2000 · « **Reply #24 on:** April 26, 2012, 05:30:35 PM »

ARVINC...good point on the trim tabs.
From the picture posted by Greg, it seems to be something near the surface.
We can see the bottom pretty well after the water column..

Chuck

Moose1am · « **Reply #25 on:** April 27, 2012, 07:30:04 AM »

I think mine was one of the early models as it came with a printed manual in the box. I bought it in the spring of 2010 I think. I could not believe it's price of only 1500 when all the other's cost around 3k. But I wasn't aware it was a newer smaller unit until after I let myself think I could buy it. By then it was too late to turn back. It's got the smaller screen as compared to the two larger units but it's in my price range.

[quote a
uthor=sonar2000 link=topic=3965.msg24098#msg24098 date=1335465430]
Moose1 when did you get the system?
there was a post somewhere about a short period of time when the transducer assembly was not quite up to par..
Look on your unit and the serial number will give us the date of mfg.
Greg, could probably check on this with the serial number..

The serial number is date coded.
The first two numbers are the year, the next two are the month and the next two are the day of the month.
As an example: if your serial number was 12010305-0159 then it would have been produced on January 3rd of 2012 .The other numbers represent the test station (05) and the sequential number of the unit that was tested at that station on that day (159th unit tested).

Chuck
[/quote]

sonar2000 · « **Reply #26 on:** April 27, 2012, 09:22:19 AM »

Moose1....you are probably before the assembly issue with the transducer...And the window for the issue was very small, with only possibly a few affected..

Chuck

planesmith · « **Reply #27 on:** April 28, 2012, 10:17:24 AM »

Hey guys I started this original post and unfortunately just got back to take pictures of the back of my boat. My issue is false traces to the left of centerline while in side image views.

I took a picture of the left and right rear transom and a closeup of the transducer mount. I circled a few things that might be causing the problem by perhaps partially blocking the sonar signals. I would expect however that all of these things are fixed to the transom the problem would be there at any speed? In my case as soon as the boat passes 5 MPH the false traces dissappear.

New step is to get some snapshots but it is sleeting here in Minneapolis today so it may be tomorrow before I can get them on the site.

Humminbird_Greg · « **Reply #28 on:** April 30, 2012, 11:50:23 AM »

planesmith,
Those false Si readings disappear after 5 MPH but are there at slower speeds. Are they there while the boat is drifting? If yes than it still could be one of the objects that you marked. Any way that you could slip the transducer out of the metal bracket and affix it to a pole that you could lower down past the boat hull and motor and see if the lines are still there? This would rule out anything on the boat reflecting the left Si sonar. If it does, than maybe you could add something to the transducer mounting plate that you have now so that it sticks farther away from the transom.

Moose1am · « **Reply #29 on:** May 05, 2012, 09:49:49 PM »

Here is a screen shot from my photobucket account. Note the bright wide line that run's parallel to the center line and just ot the left of it. This is in the water column part of the image. It's as if there is something dragging right below the transducer about 2 to 4 ft below the transducer. But there is nothing there. Unless this is being caused by air bubbles. I'm fishing out of a 1978 Fisher Marine Water Strider III Aluminum Bass Boat. I don't think that I had the trolling motor in the water as I normally retract that back up onto the bow of the boat before running the gas motor and using my SI unit.

sonar2000 · « **Reply #30 on:** May 06, 2012, 09:23:47 AM »

Moose, not sure of the exact beam that the transducer puts out, and it could vary a bit unit to unit.
This thin line (clutter) may be the result of the transducer reflecting the very top of the water.
This could also be due to a very slight tilt of the transducer from horizonal level. (boat weighting or person positoning in the boat. Equipt placement , etc.)
As long as it is minimal I would not worry about it..
Since we run our units portable and on an adjustable pole we generally have the treansducer 1 foot deep in the water. Dont see this line at that depth.
Chuck

Moose1am · « **Reply #31 on:** May 06, 2012, 12:04:56 PM »

Hey Chuck:
That may be it. I too am not familar with the exact shape of the beam of sound. I'll check to see if it does that when using 800 Khz frequency as I think that sound wave is directed more towards the bottom and more away from the water's surface. I saw some diagrams that showed the difference in the 455 and 800 Khz beams.

I did add some lead to the left side of my boat to make it list more to port. Before it was listing towards starboard as I am heavier now than when I first setup the mount. I'm about 50 lbs heavier these days than in 1986 when I mounted the metal bracket on my boat.
I used some lead shot (shotgun lead shot) in Caldwell Bags so I can add or remove them easily to either side of my boat. I even added some weight lifting weights to the port side as well to make the boat side flatter in the water and level.
I check the coiled transducer wire last night and it was laying down near some other electrical wires. I moved it up and away from those wires and tied the coiled wire until a support to keep it away from the other electrical wires. I had the power wire for the humminbird coiled up next to the transducer wire and didn't think that was a good idea. So these are not seperated in space now.
I'll play with the boat and do a few things to see if I can clear up the noise lines. I'll also go out and play with the SI screen when it's set to 20 ft and check for multiple lines as someone else suggested.

It's a minor problem right now and is not keeping me from fishing. I'm not worried about it right now. Just more curious as to what may be causing the line.
I did get my SDHC card out of the control head and put it in my computers card reader. So I was able to see the files using my Photoshop Elements 9 program. They didn't show up in the Organizer at first until I inported them into the Organizer. I'm still trying to learn how to use Photoshop Elements. Now I can see them.
I guess I may need to get a 3 rd party program to view my recordings. Any suggestions on which programs to use to do that?

sonar2000 · « **Reply #32 on:** May 06, 2012, 07:22:11 PM »

Moose, A lot are happy with Humviewer. Martin has donated his time to write and maintain this program. You can get the download by going to his website.
http://humviewer.cm-johansen.dk/

Another is the YellowFin and available for download on this forum under third party software.
you will need the converter also for YellowFin.
Deepview is also good.

For mapping you can use 3DFMaps http://www.3dfmaps.com/ ....or SonarTrx or Dr. Depth. Those are for pay programs..

Chuck

Moose1am · « **Reply #33 on:** May 07, 2012, 12:20:57 AM »

Thanks for the help. I downloaded and figured out how to run HumViewer and it helped me find one of my PVC fish attractors that I have been having a hard time seeing on my screen. It showed up at the very end of my last record. I was patrolling around the spot and going back and forth over the area where I put the PVC crappie trees in the water. These PVC trees are ten ft long and have ten foot long arms on them but I have a hard time seeing them on my sonar screen.

Hummviews playback on my computer made it so much easer to see things on the computer's screen. No sun reflections to contend with like out in the field.

Now I have to figure out how to make it work with Google Earth. I think I may have deleted my google stuff. I have too many programs on my computer now that want to connect to the interent without my permission. All those network connections slows the computer down and opens up too many ports.

Quote from: sonar2000 on May 06, 2012, 07:22:11 PM

Moose, A lot are happy with Humviewer. Martin has donated his time to write and maintain this program. You can get the download by going to his website.
http://humviewer.cm-johansen.dk/

Another is the YellowFin and available for download on this forum under third party software.
you will need the converter also for YellowFin.
Deepview is also good.

For mapping you can use 3DFMaps http://www.3dfmaps.com/ ....or SonarTrx or Dr. Depth. Those are for pay programs..

Chuck

sonar2000 · « **Reply #34 on:** May 07, 2012, 08:06:38 AM »

PVC pipe is used by our Corps of Eng on the lake for fish attractors. We have run scans on them but it is a bit difficult to pick up. Kind of like radar and stealth aircraft, the sonar tends to slide around the pipe rather than reflect or absorb.
But with some algae it does come to view after a while..

Chuck

Moose1am · « **Reply #35 on:** May 07, 2012, 11:01:43 AM »

That's exactly what I found to be true. Stealth technology describes the effect quite well.
I was finally able to see these PVC attractors on the recording using Humviewer. I had made a pass over the area and then turned around and made another pass. The second pass showed the PVC attractor. Actually I put several of these in the area. There was at least 5 of them put in this area. I could see one very well. I could even see all the arms on the main brach. This is the one I put foam into the top to make it boyant at the top and stand up straight off the bottom. I think I saw two others on the recording as well. One was on the land portion of the screen and the other was in the water column portion of the SI screen. There was a cloud of air bubbles or turbulance in the area which obscured some of the area. These have been in the water for a couple of years now. I read where some people take sand paper or something abrasive to rough up the surface of the PVC pipes so that algae can attach to the PVC faster. I didn't take the time to do this. I stopped doing PVC fish attractors as the price of PVC pipe was getting too expensive and the place where I got my PVC pipe shut down. They basically priced themselved out of business as they kept rasing the price of their pipe. Other larger stores like Home Depot, Lows and Menards drove them out of business I guess.
I glad that I finally downloaded and installed Humviewer. It works well and I like the way I can change the colors on the screen by right clicking on the screen.
I did notice that I used different frequencies in my recordings. Sometimes I use the 800 KHz Freq an other times I used the 455 KHz Freq. I think I saw the PVC attractors using the 800 KHZ frequency on my SI.

sonar2000 · « **Reply #36 on:** May 07, 2012, 12:10:52 PM »

800 may give you a better picture. The corp added some foil danglies to the arms of the pvc stand and that does help a bit.
When we scanned over the pipe area we did see our water bubbles on subsequent passes. The motors do churn the water up.

Chuck

Humminbird_Greg · « **Reply #37 on:** May 07, 2012, 04:08:13 PM »

Moose,
You have the lines on each side of the centerline. They are stronger on the left side than they are on the right.
Do these happen while drifting?
The ones on the left are stronger/brighter due to their distance from the transducer (farther than on the right side). We do some near-field filtering to help dampen Si sonar returns from very close to the transducer.

Part of the problem with seeing PVC on sonar is its acoustic impedance which is closer to that of water than some other materials. This makes it sonar stealthy as it does not reflect sonar well.

Hmmm, maybe some non-toxic metalized paint for the next batch of fish attractors would work better? Or even a sealed ball would make them easier to see. Remember though: if it is easier for you to find them than it is also easier for others to find them as well.

Moose1am · « **Reply #38 on:** May 08, 2012, 12:42:22 PM »

Hey Greg:
I read that humviewer looks at the raw data file from the Humminbird unit and does not filter the data like the Humminbird Units do. This makes it easier to see the PVC trees perhaps.
I was out on the lake where I sunk at least 5 pvc crappie trees. Each tree is ten ft long and with ten small arms passing though a 4" OD ten foot long pvc pipe. The arms stick out 5 ft on each side of the tree base. These arms are 1" od and ten foot long and there are ten of these on each tree. Each tree is filled with concrete in the last 2 ft section of the base and some of them have foam float material stuffed into the top 3 ft of the tree to make the top of the tree boyant. This helps the trees to stand up straight off the bottom.
I put these trees in a few years back and in a spot that's easy for me to find. I know exactly where I put them as I used landmarks that were close buy on the shoreline and my GPS hand held unit to make the Waypoints for each tree. I was anchored at the time or tied to the shoreline with a long rope. So I know where they should be unless some divers went down to pull them up out of the water. I feared that the local dive team has done just that as they practice diving and recovering operations in these lakes sometimes.
Anyway I've been trying to see these PVC trees using my 898 unit and crossing over the area multiple times over the past three or four years. I only got one screen shot showing one of the trees on the screen. All the other times I could not see any of the PVC trees on my unit's screen while searcing for them in real time. Perhaps its the filters turn up to much. I even set the sensitivity up to 20 to make it easier to see weaker sound returns.
The last time I went out fishing I was going over this area and made a Humminbird Recording of a short track. At the end of the track I went over the area where I put the trees. I didn't see anything on the screen at the time. Game warden was in the area and distracted my attention. But when I got home I finally decided to download and install the hummviewer program and use it. I had tried to use it in the past on my older computer but gave up. Now that I was able to use Humviewer and play around with it I took my SDHC card out of my 898 unit and started to examine the recordings.
The last recording I made was the one that finally showed three of my PVC trees in the water. Some of them are in shallower water than the others. All are deep enough to be out of the way of swimmers etc. And some of them have fallen over on their side as they don't have anything in the top section to make them float. If I could still dive (scuba dive) I'd get some dive partners and go get them and rebuild them with floatation in the tops. They work better standing straight up from the bottom IMHO.
But I'm happy that I finally was able to see that they are still right were I put them. No one will see them easily on their sonars unless they are right over the top of them. They don't reflect sound waves back very good so they are very stealthy.
When I'm on the water I and using the smaller 898's screen and with the sunlight shining on the screen it's very hard for me to see things on the screen or pick out any tiny details. Now after the sun goes down it's easier to see the screen or if it's cloudy I can see the screen better.
But using Humviewer I can use my 26" flat screen on my computer and without the sun shining on the screen and it's much easier to see details in the recordings. So that's why I was finally able to see the PVC trees using humviewer.
I use the 455 KHz frequency setting for my SI scans. I'm wonder if the 800 KHz frequency would show them better? I was around 100 ft away from them as I had the SI range set to 100 ft in both diretions. Chart speed and boat speed also have an affect on the quality of the pictures I'm told.
I'll have to play around with those some day and see if speeding up the chart speed improves the image quality. It should draw a few more pixels on the screen of objects that are seen.
I was able to see the air bubbles after I made a pass though the area and turned around for a sceond pass. The propeller made these bubbles in the water on the first pass and had not disipated before I made my second pass. Or it may have been left over air bubbles from another boat that was in the area at the time. Come to think of it I only made one pass on this recording so it had to be air bubbles from the other boat. Bad timing on my part. I have to repeat that experiment.
I'll do some drifting next time I'm out with the boat and see if those line go away. Yes I noticed that they are on both sides of my screen.
I mounted the transducer metal bracket on the starboard side. I'm not sure which way my propeller spins. Clockwise or counterclockwise as it makes a difference from what I read in the Humminbird manual. I mounted the metal bracket on my boat years ago before they came out with the 898 unit. The older humminbird LCR unit's use the same metal mounting bracket thats still in use today. So I didn't move the metal mounting bracket and just exchanged transducers when I got the new 898 unit. My older Humminbird LCR 8000 is still used up on the bow of my boat and I intalled a new trolling motor mounted transducer for the LCR 8000 unit. It still works well as long as I keep the power cable's holes clean. They tend to get a green corrosion on them and the power won't get to the unit unless I keep the little holes cleaned out. I use a tooth pick to clean them. Works well and won't remove the metal coating on the pin holes. Wish that they would use a different type of power connection that's more solid and robust.
Anyway the lines are not a big problem for me but I was just curious as to what's causing them.

sonar2000 · « **Reply #39 on:** May 08, 2012, 08:32:32 PM »

Moose, I did not see any difference in the viewer. Primarily it is the PVC and the way the signal slides around it..
chuck

Moose1am · « **Reply #40 on:** May 09, 2012, 08:52:54 PM »

It's just that in the sunlight it's harder for me to see the screen as vs when I'm inside using the humviewer program and the computer monitor which is much larger in size.

I went out last night and reviewed the same movie and could see the PVC tree's clearly on the Humminbird 898 Screen. So it's really a matter of the smaller screen but more it's the problem with glare in the sunlight outside. I even have a raptor cap on my unit and it's still hard to see due to the glare coming off the water.

sonar2000 · « **Reply #41 on:** May 10, 2012, 04:05:08 PM »

Moose, that will make a difference. Indeed the screen is not real light comforting..Even on the 1197 or 1198 it makes a difference with an external viewer.

Chuck

Moose1am · « **Reply #42 on:** May 11, 2012, 01:25:12 AM »

I have an golf type umbrella that I use to get some shade while fishing but it also works good at blocking out some of the sunlight so that I can see my SI Screen during the daytime hours. I went out tonight and was going to make a few more recordings on my local lake but ran into a friend and we started to BS so much that it got dark before I got to launch my boat. Got cold too and mosquitos started biting as well. Had to go home before I was ready too. There's always tomorrow.

This afternoon I was playing with the SI unit on the boat which was parked in the driveway. So I put the umbrella up so as to see the screen better. Now I wish I had a bigger umbrella. LOL

sonar2000 · « **Reply #43 on:** May 11, 2012, 11:27:06 AM »

Moose, I need to get back up to the Corp of Eng area and try some sonar on the two new PVC trees with the alum pie danglies..

Chuck

Moose1am · « **Reply #44 on:** May 12, 2012, 12:51:38 AM »

Switching to resistor type spark plugs may be a good idea. I have my Humminbird 898 hooked up to the battery that runs my gas motor. So you may have something there. I'll have to try buying and installing some new spark plugs for my 35 HP Johnson Motor. It's an older motor from 1978.

I'll try to take the boat out tomorrow and do some testing. I was wanting to get it out today (friday) but was too tired to go out today. I did tilt the main motor up a bit more so at to get it out of the way of the left sonar sound waves.
Did the OP (original Poster) ever get his unit figure out? Sounds like there are three of us that have the same problem with this 898 unit and the new software installed.
What bothers me the most if that the problem was not there before. At Least I never noticed it in the past. So that makes me wonder if it's due to the new softare update. Nothing else has changed. I mean I was using the non resistor spark plugs before and I didn't get this interference problem. And my transducer's location and setup has not changed a bit? Just wondering why all of a sudden it started happening or I started to notice these lines.

Quote from: yenrec on April 26, 2012, 09:57:36 AM

I was se

arching this the other day because i noticed it on my brand new unit as well, mine occured mainly at faster speeds, but once again only on the left. I may have found it on humminbirds website that if your unit is hooked up to your starting battery, it may pick up interference from the alternator charging the battery, also they mention switching to resistor spark plugs or something of the such if it has to do with interference under power. Ill see if i cant find the exact link and postt it up.

Moose1am · « **Reply #45 on:** May 13, 2012, 09:54:12 AM »

Humminbird Greg:
I did some testing Saturday. I found that the lines are there no matter what the SI range is set to. They do appear larger when the range is set to 20 ft as compared to 100 ft or more. Secondly when I shut off the gas motor the lines are still there while I'm drifing. So it's not air bubbles or anything.

I tilted the 35 HP Gas Motor up as far it it will go using the holes and the metal rod to set the tilt angle on this motor.

Perhaps the tranducers' sound waves are not as focuces at they should be and some are leaking out of their intended or designed narrow path and hitting my motor metal on the left side? It didn't do this before.

I fear that some of the sound is hitting something right below the boat or at the surface near the boat or the engine and not getting sent out of the left side as far as it should.

I make a recording of my testing and tried several different settings during the recording. I have not looked at it yet on Humviewer but will soon. The SDHC card is stilll in my Humminbird Unit and the boat's in the garage. It's hard to reach the unit as the boat is right up next to the side of my garage and I can't squeeze back in there between the boat and the stuff stored in my garage along that wall. I have to climb up inside the boat to get to the control head and the SDHC card or move some things out of the garage so as to pull the boat out of the garage. But it's raning today and it rained yesterday too. I'll wait until it stops raining and pull the boat out to get that card and check out the recording on humviewer.

Do you know if one can take snap shots off the recordings while using humviewer or while playing the recording back on the control head it self?

The line is still present on both sides with the line on the left side being wider and brighter than on the right side. That's not right.
PS: my friend who also has the same unit was at the lake yesterday afternoon but he had to leave as he got called back into work on Saturday. He was on call and is a supervision at the company he works for and had to leave the lake to get back to work. So I'll get with him when he has some time free and we will swap control heads on our boats and do some testing on the control heads and transducers. He's got a triton bass boat with his transducer mounted on the jack plate bottom of his motor. Where mine is mounted right on the hull of the boat on the left side. I think his is too close to the prop as it's closer than 18" to the prop. While mine is mounted farther to the right side of my boat and away from the motor's propeller.
PSS: I still have another metal bracket that I could mount on the Left Side of my bass boat (Aluminu Fisher Marine 1978 Water Strider III) and do some testing. But I'd rather not drill anymore holes in my transom.

Quote from: Humminbird_Greg on May 07, 2012, 04:08:13 PM

Moose,
You have the lines on each side of the centerline. They are stronger on the left side than they are on the right.
Do these happen while drifting?
The ones on the left are stronger/brighter due to their distance from the transducer (farther than on the right side). We do some near-field filtering to help dampen Si sonar returns from very close to the transducer.

Part of the problem with seeing PVC on sonar is its acoustic impedance which is closer to that of water than some other materials. This makes it sonar stealthy as it does not reflect sonar well.
PSSS: I can level my boat out from starbard to port using weights and shifting my postion on the bench seat to make the boat level from side to side. But I wonder if my boat is level from front to back? I can vary the speed of the boat to raise the front end some before it starts to get on plane. But I wonder if the boats position while going slow at idle would affect the sonar waves from side to side?

Jimliner · « **Reply #46 on:** May 13, 2012, 06:09:26 PM »

In sim mode I have trace only on the left. Similar to yellow & orange graph above. This was after playing with some settings in sim mode. Hasn't seen water yet. Just wrapped up install on Tracker Targa. Weather permitting going out Tuesday.

Humminbird_Greg · « **Reply #47 on:** May 14, 2012, 11:39:14 AM »

Jimliner,
Don’t worry about what it is showing in the Simulator mode as this is not using the transducer you have on your boat. Wait until you hit the water to see if you have the same thing or not.

Humminbird_Greg · « **Reply #48 on:** May 14, 2012, 11:41:16 AM »

Moose,
I think that you need to try temporarily installing your HDSi transducer on a pole and lowering it down below the level of the boat hull and motor to see if the lines go away while you are drifting (with the motor and all other devices turned off) or not.

Moose1am · « **Reply #49 on:** May 14, 2012, 01:08:21 PM »

I'll have to try that. By the time all this testing it done my warranty may be over! This takes some time to do.

Testing specie ah it works Just installed a new spell checker for IE 9. This one works with MS Windows 7 64 bit version where as IEspell didn't work and/or contained a virus of some kind according to my security software. Hope this spell checker works better than the old one.

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