Another electrical interference thread

[Hez]

I have a Humminbird 1199 at the console that is wired direct to my cranking battery. I was having some interference problems only visible on the side imaging / down imaging (more side imaging), and I re-ran the transducer cable and power cables - making sure to separate the transducer cables away from any of the power cables. Doing that improved my interference, or so I thought. I was out graphing last weekend and when I increased my side imaging to 250' on each side...the interference was back and seemed to be worst than ever. I dialed the range back down, and most of the interference was gone.

I'm thinking the interference is a result of being connected to the cranking battery along with the motor.

I am considering a small dedicated 12v battery just for my graphs (Livescope with EM 93 on bow and Humminbird 1199 at console).

When I research the topic, it seems like consensus is to get a bigger battery...but I'm running a 31 group commercial battery from NAPA...recommended by the bbc....and voltage isn't the issue...it's interference.

Also, as I was listening to BTL today, they had the guys from the Bass Tank on and they recommended a dedicated battery for electronics.

What do you guys think?

Can anyone confirm my theory about the source of the interference?

Any input is appreciated.

[CRAWFW]

I have a dedicated battery for my electronics and seem to get interference on side imaging as well. But only going thru the Ethernet hub. If I turn off the hub and run my units in stand alone mode it goes away.
Helix 8 MSI+ up front and Helix 7 MDI at console.
Along with an Ultrex but not using the 2D transducer in the motor.
Also the left side imaging seems weaker than the right. Made several passes around bridge pilings the other day and could barely see them on the left side.

[Wallace]

I’ve seen some where on this forum someone using a ring terminal under any one of the Ethernet connectors on the hub to “ground” out the hub to the hull. Solving there interference .

[Royt]

250 feet on each side, 500 feet total. WOW, amazing if you can actually see any detail at that distance!

[Hez]

250 feet on each side, 500 feet total. WOW, amazing if you can actually see any detail at that distance!

That is looking for structure only...and when you are idling a big bowl of sand full of water...1 blade of grass or 1 anomaly sticks out like a sore thumb. Use that just for idling around scanning. If I'm looking for fish, or details - I usually run about 75 on each side

[bobcoy]

Have you tried a ferrite choke on the transducer cable right at the back of you 1199. ( the donut shaped one that you wind the cable through several times?) I bet that will help

[CRAWFW]

I’ve seen some where on this forum someone using a ring terminal under any one of the Ethernet connectors on the hub to “ground” out the hub to the hull. Solving there interference .

Sounds like a good thing to try. I can’t really imagine grounding to fiberglass being effective but I’ve seen stranger things.
Possible static electricity buildup?
I do know I got shocked for the first time in my boat reaching into the live well where I keep a net full of minnows. It freaked me out. Never had static discharge on a boat before.

[bobcoy]

Sounds like a good thing to try. I can’t really imagine grounding to fiberglass being effective but I’ve seen stranger things.
Possible static electricity buildup?
I do know I got shocked for the first time in my boat reaching into the live well where I keep a net full of minnows. It freaked me out. Never had static discharge on a boat before.

You were the one with the charge. the water was grounded. The grounding on the ethernet switch helps because the ground for the boat is through the motor to the water.

[Hez]

Have you tried a ferrite choke on the transducer cable right at the back of you 1199. ( the donut shaped one that you wind the cable through several times?) I bet that will help

I will research that option, thank you for the input.

[Crappie Bob]

Dedicated battery for the electronics. Cable from the ground on that battery to the ground on your start battery. Might help you out. I did that plus grounded to the transom brace but I have a tin boat. I think what fixed it was the NEG cable from one to the other since the motor is in the water as ground. Can't hurt to try.

[Hez]

Dedicated battery for the electronics. Cable from the ground on that battery to the ground on your start battery. Might help you out. I did that plus grounded to the transom brace but I have a tin boat. I think what fixed it was the NEG cable from one to the other since the motor is in the water as ground. Can't hurt to try.

Thanks Crappie Bob, I actually ordered (prior to the ferrite choke recommendation) a small 12v 18ah battery to run just this unit. The 1199 specs out to use 1.3 amps, so I should be fine in a long day of fishing.

[Dogfish_Jones]

I think the interference problem is all caused by some type of grounding issue. Find that, you have found the problem.

[bobcoy]

Sounds like a plan Hez. If the interference is RFI it can be broadcast through the air so your choke may still be needed. If you should hook up any grounding rigs make sure you do not ground to you hull, anywhere besides the - side of your starting battery and you are risking electrolosis. JMHO Bob

[Crappie Bob]

It took me a while reading all I could find here, and other boards, and asking the people that have been here a long time to get it figured out. Mine works like it should now. And I'm not really concerned about electrolysis since only the grounds are connected.

[Hez]

I have a dedicated battery for my electronics and seem to get interference on side imaging as well. But only going thru the Ethernet hub. If I turn off the hub and run my units in stand alone mode it goes away.
Helix 8 MSI+ up front and Helix 7 MDI at console.
Along with an Ultrex but not using the 2D transducer in the motor.
Also the left side imaging seems weaker than the right. Made several passes around bridge pilings the other day and could barely see them on the left side.

It actually sounds like you need to check your transducer installation to correct the weakness on the left side. It sounds like the boat may be listing to the right slightly and possibly weakening your signal.

[Hez]

Sounds like a plan Hez. If the interference is RFI it can be broadcast through the air so your choke may still be needed. If you should hook up any grounding rigs make sure you do not ground to you hull, anywhere besides the - side of your starting battery and you are risking electrolosis. JMHO Bob

Received the new battery last night - installed it and wired the HB up to it. Turned the unit on and cranked the motor for a second, and still seems to have interference from the motor. I double checked my transducer cable to confirm there was as much separation as I could create.

I've ordered the ferrite choke ring to now install to try and eliminate the interference.

[bombercraw]

Received the new battery last night - installed it and wired the HB up to it. Turned the unit on and cranked the motor for a second, and still seems to have interference from the motor. I double checked my transducer cable to confirm there was as much separation as I could create.

I've ordered the ferrite choke ring to now install to try and eliminate the interference.

I feel your pain. I am dealing with RFI issues as well and have spent countless hours trying to trouble shoot to resolve. It's a real PITA !! My issue is the bow unit and RFI from the trolling motor. I believe the electronics and trolling motor companies should figure out how to make their products so we consumers don't have to deal with this crap. There should be a way to fool proof their products to avoid RFI issues. It's extremely frustrating. It's been my experience that the best "fixes" to eliminate or reduce the RFI is some sort of grounding solution. The ferrites didn't make any difference whatsoever for me in reducing the RFI issues. Some have had luck with them, but I didn't.

[Crappie Bob]

Actually what fixed all mine was a dedicated battery solely for the fish finders, absolutely nothing else hooked to it but the onboard battery charger. Grounded that battery to the outboard battery and then to my transom. I have a tin boat, but I think just grounding the 2 batteries did it because the outboard is mounted to the boat so it is already grounded...I know I about pulled out what was left of my hair over it. And calling the manufacturer was a fart in the wind as far as I am concerned. Once they sell it, it's yours

[Hez]

After messing around with it last night - I was able to eliminate the interference...but I did that by running the transducer cable on the outside of the boat, to the unit at the console.

I know...I know...I can't run like that...but at least I was able to eliminate the interference temporarily...so I know it's possible...but anytime it got near the motor...boom, interference.

I could tell a difference the the ferrite core ring I got...but it turned out to be a small one that I could barely wrap 6 times. I'm getting a larger one that can wrapped a lot more times.

Actually what fixed all mine was a dedicated battery solely for the fish finders, absolutely nothing else hooked to it but the onboard battery charger. Grounded that battery to the outboard battery and then to my transom. I have a tin boat, but I think just grounding the 2 batteries did it because the outboard is mounted to the boat so it is already grounded...I know I about pulled out what was left of my hair over it. And calling the manufacturer was a fart in the wind as far as I am concerned. Once they sell it, it's yours

That may be an idea worth considering. I have a glass boat of course, but can I run a ground wire back to my jackplate? That seems to be the most logical place to establish a ground....any body know?

Thank Crappie Bob

[bobcoy]

A second ring might do the trick. Have you tried using the filter setting 1 higher? If that troubleshooting was in the garage don't do anything else till you try it in the water. The water has a big effect. Your outboard provides a ground to the boat when its in the water. Bob