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Strange fishfinder phenomenon


Tim Bromund

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OK I guess it's time to look for some opinions on this before the next boating/fishing season starts.

2 years ago I took advantage of the smokin' deal that Bethel Marine had and retired my old LMS350A for a new Ray DS600X color graph. Overall I have been extremely pleased with it, but this past summer it would occasionally do something really odd. Not all the time, but every so often, when I had the transducer side rigger running shallow (40-50 down), it would lose bottom signal and start reading the rigger ball as the bottom. It didn't matter where I had the sensitivity level set, but I really don't think it's a situation that should EVER occur.

It is the Airmar P66 dual frequency transom mount transducer.

Anyone have any thoughts as to what might be causing that and how to correct it? I usually had to either swing the rigger 90 deg out, perpendicular to the gunwale to get the ball out of the transducer cone, or make that the deep rigger so that the blowback would take it out of majority of the cone. I usually have the other rigger (my probe rigger) as the deep one.

Thanks,

Tim

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Tim,

I have the same FF and have the same problem. The shallower I had a riggers the more it would happen. I would adjust the sensitivity and turn it off and on to get it to reset itself but even that didn't always work. Very frustrating to say the least!

Brian

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Dear Tim,

The mfger may give you an answer or they may give you smoke & mirrors about this type of problem. After many hours of operation, specific errors can be found in many types of "market targeted sonar equipment" The Great Lakes & the cold dense water produce very interesting problems for the sonar. Operating a particular piece of equipment on someone else's boat is the best way to make a decision on what you want to use! Hummingbird spends millions on sponsorship & advertisements. Direct marketing thru the boat mfgers is their way to promote & sell. Their equipment is seldom bought a second time. (In my experience). I also learned in the 1980's that the sonar logic could be designed & programmed to produce wonderfull screen content that wasn't there!! A good sonar and a good operator can be a powerfull tool to find fish & bait. Getting this equipment to work at cruise speed is very challenging but very rewarding for the educated fisherman.

........Respectfully submitted......Jet Boat Bill

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Tim,

First I would like to say Happy New Year to you and your dad.

Second, I would like to inform you that your problem is not spacific to your finder. I have the same issue with my Hummingbird. This issue happens more when I am on the big lake due to the currents and blow back. It seams to just be in the cone more on the big lake than back home on the Cape (use of heavier weights). My conclusion was to either chnge the angle of the transducer or I speed up for a short time to get the ball out of the cone. I also found that on those days where the fish were higher in the water column if I only used the wider cone it did not happen.

Richard

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Thanks guys, I'll definitely contact Raymarine and see what they say. I'll also adjust the angle on the transducer forward a little bit before i drop it in the slip this spring and see if that helps. Problem is, I don't have a tow vehicle anymore and borrow the diesel truck from work in the spring and fall for put in and take out, so once it's in, it'll be a big hassle to pull it for further adjustments.

Just thought it was odd, as I never had that happen with my old Lowrance LMS350A in the 12 or 13 years I ran it. When passing over a big ball of bait, this new Raymarine unit has also frequently read the top of the bait pod as bottom

Big Dave, it wasn't in the spring, it was August chasing offshore steelhead.

Tim

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When passing over a big ball of bait, this new Raymarine unit has also frequently read the top of the bait pod as bottom

My 500 does the same thing with really large bait pods. Never had the weight issue though. (knock on wood)

Tom B.

(LongLine)

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Happy new year!

Your problem sounds very interesting. and similar to mine. I had a humminbird 788ci. worked great for a few months then started doing the same thing. i sent it to mfgr and they sent it back with a new transducer. i put the new one on. Worked good for a week and did it again. It worked great on ontario, when i came back to my home lake, seneca, it did it again.. Needless to say I gave up, sold the boat and the bird. time to start new, LOWRANCE is now my only choice. i wish you luck, and remember youre not alone..

see ya on the water,

Nick

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My lowrance does the same on occasion. A quick sharp s turn sometimes fixes it. Or I will spin the rigger from the rear to out the side and back.

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Great topic started here tbromund. Maybe we'll all learn something from this one.

I have the Furuno FCV-620 and it will do the same thing from time to time. Not often, say a couple times a season. I think the lock on rigger balls or dense bait balls is probably more to do with the GAIN in the automatic mode than a messed up unit.

If it happens on a bait ball with my unit no big deal. The unit will reset as soon as the boat is past the bait ball. If my unit locks on the rigger ball and doesn't reset in a minute or two I just raise that ball up till the unit resets and locks on the bottom again. Usually resets and locks on bottom before the ball is all the way up.

Mine doesn't do it enough for me to even bother changing anything. I like the way it tracks and clearing the problem doesn't take much so I'll leave well enough alone.

It will be interesting to hear what the manufactures have to say about that phenomena. There are a few of us interested in what is really going on it seams to be common with several different brand units so if any of you guys happen to get any feedback from the manufactures please report back with what they have to say about it.

Thanks and Happy New Year!

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Tim,

First off im surprised this is something you just ran into. It happens primarily when the perfect storm of depth sensitivity and downrigger placement converge. So back to the beginning All Raymarine Fishfinders produced the last 6 or so years are equipped with Digitally Adaptive Transmitter Receiver with infinite receiver bandwidth settings and digital filter. I might explain it more like this imagine listening to your radio and having an equalizer tune every sound of every note coming back to your ears. Your Raymarine fishfinder does this leaving behind the traditional arches and painting a remarkibly accurate portrait of the image below your boat.

http://www.raymarine.com/SubmittedFiles ... .tn.lg.jpg

Long story short your Fishfinder when run in auto mode is in some cases over sensative. If you were in Salt water examining wrecks the auto feature on low med or high is unbelievable. The Downrigger throws it a curveball. Set the FF to run in manual mode and adjust the sensativity to run between 60 and 70 % this should be good for up to 400 feet or so. Also set scroll speed in manual to 100%. Finally set your depth manually as well upper 100 ft? 200ft? In this mode your depth will most likely read one of your downriggerballs since it is a hard target it will maintain a solid line however it will read all that is below as well. At any instant an overall depth is needed scroll down the range and the machine will pick up the bottom for you. In the end the machine is remarkable and is overbuilt for what we do we basically dumb it down a bit by placing manual limitations on the parameters set at the factory. There are some other things we can do with zoom and what not to give you overall depth readings all the time but it might be better to explain in person. Feel free to contact me anytime. Raymarine is bringing some crazy new stuff to the market this season geared towards us Great Lakers.

Hope this helps

Kevin Jerge

716-863-1001

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Thanks Kevin,

considering that it replaced a 13 yo Lowrance LMS 350A, I'm not at all surprised I never saw it with that old dinosaur of a unit. :)

It may just have been that with August being as screwy as it was this year, I ran offshore for steel more than I normally do.

I'll probably try to get a hold of you before the season starts to figure out the best settings for this unit.

Tim

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  • 3 months later...

Just wanted to follow up on this and mention that Raymarine did respond with pretty much the same as Kevin did above, although with a lot less detail. I'm just going to have to spend some time playing around with the manual settings this year. At least Kevin's info gives me a good starting point.

Tim

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I have a Raymarine L750 that I ran a lot like he put down on here. Mine will lose bottom on a bait pod but I don't remeber it doing it with the cannon ball. Every time out I would have to adjust the senativity and some times while on the water. Mine was BW so I would take it up till screen was mostly black then back it off watching the cannon balls getting a light ray color and clling it good. If I lost the racking of the balls I would kick it up a touch till I got them back same if screen got too much clutter drop it down..... I know yours is color but maybe this will help some.

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  • 2 weeks later...

Tim, I'm running a Ray C120W with the DSM300 sounder, and from time to time I've had the same experience. At first, when I was still learining the unit, I would just bump speed to get the weight out of the cone momentarily, but after getting a comfort level with all the default settings, I started to play the manual stuff. I found that manual sensitivity was best set at 70% as Kevin stated. I'm running the B60 tilted element thru-hull on the same hull as you (24 Thompson).

Kevin- Any ideas about manual settings to dial in a good pic when on plane with this unit?? I have really been frustrated in trying to do so. Is it possible that the B60 flush mount thru-hull has too much airation going over it at speed?? What are my options? Really want to be able to run and see the best pic possible.

Thanks,

Scott

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You would have to be more spacific as to what you are seeing or not seeing. Keep in mind at speed much of what you are looking for will likly be a flash in the pan unless you stumble over the mother load of bait. If the picture seems very busy than its possible it may be ducer placement. The tilted element is great for not producing large amounts of cavitation however mounted too far forward on the vessel or near a through hull fitting may produce these results. Next time out get me a shot of your ducer placement. Also with a blank compact flash card in the machine stop your scroll while running. Press and hold the data key on your machine. This should capture and store a jpg image on the card that you can post here.

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Kevin, I rarely see anything appear on screen while running although I still have a return as far as depth is concerned. Ducer is placed between Keel and 1st Strake, and approximately 3'- 31/2' forward of transom bottom (directly beneath crank pully of engine and to starboard side). Again it's a B60 flush mount/tilted. As soon as I come off plane I immediately see a great picture. I am from Ohio, and will be up for the last weekend of the LOC, if I get the chance I'll swing by the shop. Thanks for the suggestions.

-Scott

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