Getting bad interferance on HB

I just got a Terrova with universal sonar and hooked it up to my HB 787c. Every time I use the trolling motor it makes the depth go crazy and the bottom picture goes away. Even when I am not using the TM the bottom does not show up well on the sonar. I have all of this installed on my WarEagle and both the power for the TM and the HB are run together in the same raceway from the back to the front of the boat. Is the fact that they are run together causing the innerferace or is there something else I should check? Thanks for any input.

I'm having the same issues with my Matrix 97 and my Terrova. With the trolling motor on. The screen is just one big bunch of crap. With it off it works right for me. But still not showing fish like the 987c-SI does in the back?
Run the motor again, Screen is covered with lines everywhere running from top to bottom.
I have read theres some kind of filter that helps this? Sure hope I can get it worked out. My Garmin unit did not have this problem. Also I think I'm right on this. But on the 200 section of the transducer is where mine does this bad.
Guess I need to get screen shots of it doing this and try to get it working right before the Fishing trip next week.
Pete

I have the same problem. I contacted HB and they sent me a kit that I installed. This eliminated most of the proble, but I still have some interference. I have a 997 on the console and a 917 on the bow---most of the problem is with the 917 with the US2.

If you guys are running both sets at the same time, they may be overlapping. Try turning the back set off and see if that helps. I had the same problem with my 2 eagles. A 640 on the console and a 480 on the troller. I shut the back one off when i moved up front and no more interference problems. I hope thats all it is with you guys. It was always when i got to water that was deeper than 10ft or so. Another thing, my boat is only 16.6ft.

If you are having trolling motor interference on your Humminbird units; call the Humminbird Customer Resource folks and see about getting a trolling motor interference kit. These were developed for the side imaging units but components of these kits will apply to the non-Si unit as well.

If the sonar is still not right when the trolling motor is off than that’s another issue.

had the same problem with the 777, called HB 3mo ago never did get the kit, sold the 777 bought a lowrance and it works fine, still have the 797 on the console. it works just great, no problems, it's not on the trolling motor .

I am (or at least was - us transducer took a dump) running the exact same
setup. I was sent the kit, it helped a little, MAYBE.
What seemed to make a great difference is the last software update I did,
4.510 I believe it is. Made night and day difference in tm interference.

The only thing is, I have to lie to it and select "dualbeam" transducer,
even though I am actually using us2. If I select us2, it goes back nuts
again, worse than before even.

But also after this update, I can't use depth offset anymore, anything other
than 0 and it hops and skips around like it can't find bottom.
Oh well, I normally can't stand it if everything is not exactly perfect, but
I'm getting used to just dealing with it - if it's working at all, living with it :rolleyes:

If you have the finder and the trolling motor connected to the same battery, that may be your problem. Try connecting the HB to a different battery and see if this changes your problem any.

I have noticed if the US2 cable is laying on the power cable, I get interference sometimes. I've gotten to watching for this.

I tied into my ground wire going to my 787c2i and run a wire down to where i have the clamp around the actual trolling motor. I stripped some of the wire and loosened the clamp wrapped it around and tightened it back up and it took out 90% of my interferrence !!! I hope this helps you guys out. Hummingbird sent me their kit and it had a piece in it they said mount to the floor of the boat. That thing was huge !! There was no way I was gonna mount it in the floor of my boat. Thank goodness this extra ground did the trick for me !!

You fellers with all the noise, do you have metal or plastic boats? This makes a difference.

Quote:

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Originally Posted by Cane Pole

You fellers with all the noise, do you have metal or plastic boats? This makes a difference.

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Metal boat here Tom.
Mine works good until I turn the Terrova on. And if the trolling motor is on high its not as bad?
May try what Jeff has done. And trick it with telling it I'm using a different transducer.

Pete

All metal boats have grounding loop problems. If you remove the ground loop, this usually fixes the problem.

If you isolate your TM bracket from your boat chassis (such as Motorguide rubber isolator shock mounts), this removes the ground loop from the chassis by isolating the boat chassis from the tm. The Ground return to the battery then becomes the cable and not the cable and the boat chassis.

Simple to check with a ohm meter. If the ground lead to your TM reads continuity (short) to the chassis, the you have a ground loop. This means that current returns from the TM to the battery thru the cable and also to the battery thru the boat chassis (via engine) to the battery negative. This constitutes two return paths (ground loop) to the battery negative thus causing the ground loop. Plastic boats don't have this problem unless someone hacked the ground wire.

Ask any good radio man about this ground loop phenomenon.

Quote:

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Originally Posted by Cane Pole

All metal boats have grounding loop problems. If you remove the ground loop, this usually fixes the problem.

If you isolate your TM bracket from your boat chassis (such as Motorguide rubber isolator shock mounts), this removes the ground loop from the chassis by isolating the boat chassis from the tm. The Ground return to the battery then becomes the cable and not the cable and the boat chassis.

Simple to check with a ohm meter. If the ground lead to your TM reads continuity (short) to the chassis, the you have a ground loop. This means that current returns from the TM to the battery thru the cable and also to the battery thru the boat chassis (via engine) to the battery negative. This constitutes two return paths (ground loop) to the battery negative thus causing the ground loop. Plastic boats don't have this problem unless someone hacked the ground wire.

Ask any good radio man about this ground loop phenomenon.

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Thanks Tom..
I may have to get you to check it when were at Paris. :D
I was with you until you got to the part about ground loop. LOL
MY trolling motor is mounted on the rubber mounts. But not the solid mounts your talking about. I may run a piece of rubber pipe up the bolts and see if that take care of the problem..
Also getting white spots showing up on the SI unit like Todd had with the new boat. The old War-Eagle did not have these. So you may have my problem nailed down.
Trade you some 1/2 oz jig for a test.:D Tied up in the color you say.;)
Pete

I use to have the same problem with an old Eagle finder and they suggested to run a ground from the negative side of the battery and attach it to the metal boat. It worked great.

Quote:

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Originally Posted by ifish

I use to have the same problem with an old Eagle finder and they suggested to run a ground from the negative side of the battery and attach it to the metal boat. It worked great.

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This can also create other problems as it introduces yet another ground loop. Sometimes it works, sometimes it doesn't.

Quote:

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Originally Posted by ShilohRed

Thanks Tom..
I may have to get you to check it when were at Paris. :D
I was with you until you got to the part about ground loop. LOL
MY trolling motor is mounted on the rubber mounts. But not the solid mounts your talking about. I may run a piece of rubber pipe up the bolts and see if that take care of the problem..
Also getting white spots showing up on the SI unit like Todd had with the new boat. The old War-Eagle did not have these. So you may have my problem nailed down.
Trade you some 1/2 oz jig for a test.:D Tied up in the color you say.;)
Pete

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I will bring my meter Pete.

Quote:

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Originally Posted by J White

I am (or at least was - us transducer took a dump) running the exact same
setup. I was sent the kit, it helped a little, MAYBE.
What seemed to make a great difference is the last software update I did,
4.510 I believe it is. Made night and day difference in tm interference.

The only thing is, I have to lie to it and select "dualbeam" transducer,
even though I am actually using us2. If I select us2, it goes back nuts
again, worse than before even.

But also after this update, I can't use depth offset anymore, anything other
than 0 and it hops and skips around like it can't find bottom.
Oh well, I normally can't stand it if everything is not exactly perfect, but
I'm getting used to just dealing with it - if it's working at all, living with it :rolleyes:

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This indicates (to me) that the us 2 may be being over driven by the transmit signal. In other words, too much transmit power. Too bad it ain't adjustable.
MOAO only.