Transducer giving false signals

[MASTER Brian]

I just bought and am installed a Humminbird Matrix 17.

I took it out tonight for a test. The water was pretty choppy and I got a lot of false signals. Very choppy picture and depths of 900+ feet. The lake is maybe 35' deep.

These readings were while underway, but when I stopped in calmer water and went at trolling speeds I seemed to get good readings.

Is it possible a setting is wrong on the fish finder or is something happening to my transducer? It has 3 places to attach it to the hull, but only 2 screws were in for the test. They say to wait on istalling the 3rd screw until it's working properly.

I put it on the starbird side of the hull, because that's where my other one is mounted and according to the instructions that's where it should be with my prop turning clockwise. It's also mounted over 15" away from prop, which is the other spec the instructions gave.

Is this just common for chop/rough waters? I thought these newer ones would read at higher speeds. What's going on???

 

[Boatist]

Re: Transducer giving false signals

That the number one problem that every hummingbird has in year past.
They would give false reading or not see the bottom at all.
I tried to help so many with the same problem finally just decided must be the design of the transducer creating it own air bubbles.

I think that problem damaged Humminbird to the point that many will never trust them again. At least I never even go near the Hummingbirds at the boat shows.

All other brands it usually means transducer not mounted deep enough or has something in front of the transducer causeing air bubbles.

Things to try is lower the transducer. Transducer should point straight down so the deep side of the transducer make sure at least 1/2 of the transducer is below the hull. If it too far away from the engine out near the chimes then may not always be in the water.

I usually suggest very near the pitot tube or just on the engine side of the Pitot tube.

Since the matrix came out have seen many less conplaints

Good Luck

 

[Texasmark]

Re: Transducer giving false signals

One thing you might try before committing harey-carey.

Mount the unit internal to the boat so as to eliminate any surface activity associated with the transducer. Then you will only see hull bubbles at speed. Location is crucial to get the best response.

The sensitivity on your unit seems to be set too high. If you have a manual sensitivity control, reduce it till the bubbles stop in your current setup; prior to any moving trans.

If electronic you should have a screen where you can reduce the sensitivity.

Obviously depth sounding will be reduced, but in a 35' lake you could be down on 30% or more on sens and get your bottom readings.....would just miss some smaller fish. Then it's a matter of how many bubbles you can tolerate for seeing what kind of fish pattern you want to see.

Mark

 

[MASTER Brian]

Re: Transducer giving false signals

I may have set the sensitivity really high. I'll check and turn it down if so. I can easily turn it back up, if need be.

Is it just as good mounting this transducer inside the hull? I seem to have 2 others that are mounted this way, which I'm not currently using. They are old and for older finders. I know the paperwork on this said it can be mounted inside or outside. I just figured outside was better.

The boat is an 86 Ranger 373V.

 

[jtexas]

Re: Transducer giving false signals

Only real remaining advantage to outside mounting is you can get surface temp if your FF has that feature. (just my 2¢)

Best way to solve that problem is to get an Eagle or Lowrance. Sorry, just kidding. I had a humminbird that did that but I'd hoped they'd have fixed that problem by now.

Usually if the 'ducer is mounted too high it goes to 0. A reading of 900 could possibly be caused by angle of attack...other words, it shows the distance from the transducer to the bottom, but it won't be the depth unless it's pointed straight down.

Or, it could just be unable to hold the signal. Could be turbulence.

Wish I could be more help.

 

[MASTER Brian]

Re: Transducer giving false signals

jtexas, I probably deserved that after getting your opinion, then going with the Humminbird.

However, I do really like this units features. The volt thing has explained a lot and I like the fact I can hook my GPS into it.

Didn't think about the temp thing, but I do like that as well. Of course I have a temp gauge on the dash, so really not that crucial, but it is nice. I was thinking of moving the dash temp gauge to the bow just because...

At this point, I bet my issue was with turbulance since it was choppy and the fact that I probably had the sensitivity turned way up.

 

[Gone]

Re: Transducer giving false signals

One thing that troubled me at first, was that I held the on button too long and put it into the demo mode. A mometary push works best.
I lowered mine to where the transducer (boat shaped) top was even with the bottom of my hull. It will still black out sometimes at speed but not very often.

CD

 

[MASTER Brian]

Re: Transducer giving false signals

So you put it down further than called for? I can try that if adjusting the sensitivity doesn't fix it.

One other thought is the back of my boat "steps" a bit where the drain plug and livewell fittings enter/exit the boat. I can't mount there, so I am up on the transom area after the step up. Should I maybe move the transducer off to the side further? I just mounted it next to were the other transducer is.

I'll take pics if the settings don't fix it.

Thanks!

 

[jtexas]

Re: Transducer giving false signals

I bleeve it needs to be even with the bottom of the pad...if you're back of the stepup then that'll be what's causing your turbulence. Chop or no chop shouldn't affect you. You can go either side...I'm thinking the prop rotation thing is just a guideline.

Very Crusty Dude might be on to something, though...hey dude, didn't it find a lot more fish like that?

 

[MASTER Brian]

Re: Transducer giving false signals

Well, they have a template to use as a guide. It hangs the unit down about 1/4" on a fiberglass boat.

If I do move it to the side more, then the main thing to be aware of is mounting it where it will be under water...correct?

 

[Texasmark]

Re: Transducer giving false signals

I had a Hummingbird from '89 and it worked just fine for me.

Internal mounting needs to be in an area where water is touching the hull when you are at the top speed where you expect to see bottom echo's.

Unit needs to point directly at the bottom at the boat attitude that you are running when you need to see the exact distance the most.

An epoxy that is bubbleless is the best and most depth finder mfgrs recommend, by brand name, the best bubbless epoxy. RTV is nice, but not a solid, it's rubbery and will loose some signal and it is very hard to get all the bubbles out which don't hurt anything other than reducing your sensitivity; course if you have too much, big deal. d

The other thing is that you want to mount it to a solid surface in contact with the water; like shoot thru solid alum or solid FG. You don't want to shoot thru an inner hull lined with FG with a balsa wood filler (or foam), then FG on the outside hull sort of thing.

Markl

 

[Silvertip]

Re: Transducer giving false signals

You might want to make sure the transducer is not kicking up at speed and then snapping back down as you slow down.

 

[dough41]

Re: Transducer giving false signals

Brian;
I recently replaced my H-Bird wide 3d Paramount with the Matrix 17 ( used the speed/temp from wide 3d) and it works fine. I do have mine about 1/8" below bottom away from strakes etc and it reads at all speeds. ( so far, knock on wood), possible turning resolution to a lesser setting? Good luck.
Joe

 

[MASTER Brian]

Re: Transducer giving false signals

Well, I looked and the resolution wasn't as high as I thought. I did turn it down.

I also noticed that where I mounted it was just on the edge of the step up of the hull. I mounted it right next to my other one. I'll move it over and hope that helps. Whats the best way to plug the holes? Epoxy Resin or something else??

 

[Boatist]

Re: Transducer giving false signals

I would use 3m's 5200 or Marine-Tex. Also if you move it you might think about mounting it on a mounting plate. That way you will never have to drill another hole in the boat.

 

[jtexas]

Re: Transducer giving false signals

I always use 5200 to seal the holes with screws in 'em, and marine-tex for the empty ones...

 

[Gone]

Re: Transducer giving false signals

Very Crusty Dude might be on to something, though...hey dude, didn't it find a lot more fish like that?

I'm not sure that found any more fish but they seem to be in shallower water!:}

My logic was to get away from bottom turbulance/air bubbles that shot under the hull. By placing it deeper, I reasoned that it would be in pure water ie no bubbles. It improved greatly by doing this but will blank out maybe 5% of the time as opposed to 80% before. Maybe it's the aluminum boat with rivited bottom???

CD

 

[jtexas]

Re: Transducer giving false signals

CD, I was referring to running it in demo mode! 8)

 

[Gone]

Re: Transducer giving false signals

CD, I was referring to running it in demo mode! 8)

I'm a Slowski! (Love that Comcast commercial)
More fish is right, and in much deeper water than the lake had that I was on.

CD

 

[xtraham]

Re: Transducer giving false signals

http://www.humminbird.com/images/PDF/hdr400gi.pdf