TM interference on Mega 360 (Helix 12 SI G3N)

[bombercraw]

I am on my last leg hoping that someone will have some additional suggestions on things to try to help me eliminate my interference problems. I started out with my old Motorguide Tour 82 which was a 2005 model when I added my Helix and Mega 360. Had bad interference with that setup and tried many things to eliminate to interference to no avail. I was able to reduce it some but not totally. As a last resort and from suggestions gained from others on this forum regarding the potential root cause maybe being wear on my old trolling motor causing the RFI issues, I decided to buy a new MG trolling motor (bought a new MG Tour 82). Once everything was installed, I found the RFI was as bad or worse than before. I have tried everything I can think of to eliminate the issue but have had no luck. Here are the things I have tried:

**Added ground wire from skeg to negative TM battery ground post-- (A little improvement but not much)
**Added ground wire from skeg to negative electronics (starting battery) battery post-- (no change)
**Tried running ground wires from skeg to various other places such as spots on the trolling motor foot pedal--(no change)
**Tried running ground wire between trolling motor battery ground to starting battery ground--(made RFI allot worse)
**Made sure transducer cables and electronics power cables ran down trolling motor bracket and not with trolling motor power cable
**Cable management--made sure to figure 8 excess transducer cables inside bow
**Added choke provided by HB between onboard charger and starting battery--(no change)
**Unhooked onboard charger wires from starting battery to test it--(no change)
**Added TM1 choke on trolling motor foot pedal power supply wires --(no change)
**Added a quantity of 5 240-mix 77 ferrites to the Mega 360 transducer cable --(no change)
**Added a quantity of 6 240-mix 77 ferrites to the SI transducer cable (transducer that came in box with HB 12)---(saw a little improvement but not much)
**Added ferrites provided by HB to various electronics power cables--(no change)
**Tried powering Bow HB electronics from separate stand alone battery outside the boat--(no change)
**Tried wrapping the various cables inside the bow in aluminum foil to shield them--(no change)
**Tried all the various noise filter settings on my HB Unit--(saw a little change but not much)
**Been on the phone with HB for countless hours trying to solve to no avail--last thing they told me is that they think it's my trolling motor and suggest I call MotorGuide
**Called MotorGuide, and explained all of this and begged for help.........they had no suggestions beyond what I have tried and told me to call HB.......LOL

Also noticed that the RFI issue gets exponentially worse while on the water vs testing in my garage. I have also tried trial and error testing on the water trying to solve this issue.

I am literally at my wits end having spent hours and hours and days trying to solve this issue and am at the end of my rope. The interference is so bad that it renders my mega 360 useless. It is so frustrating to spend thousands of dollars on electronic equipment to have an issue like this that makes them unusable.

I am hoping that someone will have some other suggestions of additional things I might try to solve this issue. Would really like to be able to use my mega 360 as intended.

thanks in advance.

[Tone357]

PM sent.

[bombercraw]

PM sent.

Thanks Tone357

[Hollada]

Take your TM to a service center and have them check the shunts and brushes.

[bombercraw]

Take your TM to a service center and have them check the shunts and brushes.

Thanks for your note and suggestion Hollada. I just installed this new trolling motor and it is brand new so I would not think there is anything wrong with the shunts and brushes.

[franktank009]

Have you tried changing the noise filter setting on your helix? If I remember it has 4 settings and I believe the settings are not progressive from low to high. So you would need to try each setting individually. I had interference when using tm my first day out with mega360 and noise filter fixed it, been great ever since.

[franktank009]

Sorry saw the note that you have tried the noise filter settings. I got nothing lol.

[bombercraw]

Sorry saw the note that you have tried the noise filter settings. I got nothing lol.

Thanks for your note. Yeah, I have tried that and everything else suggested and things I have read. Not sure what else to try as nothing has worked. Praying that someone out there has some additional suggestions that I have not tried. This has been a real PITA !!

[Dirtyeggroll]

Have you tried it on the water or just in the garage/shop?

[bombercraw]

Have you tried it on the water or just in the garage/shop?

I have done both. It's actually worse on the water vs in the garage/shop.

[bobcoy]

I saw that in your initial post. That is counter to what most of us experience. Question. Did you remove all those ground wires you installed? With as many remedies applied there are some that might in fact complicate the troubleshooting. To simplify the project perhaps go back to the way things were immediately prior to installing the new trolling motor. You said you had solved the interference(mostly). About a dozen years ago I got into a similar quandary as you have reported and I was troubleshooting with my boat on a floating hoist.(totally insulated from any ground(water or otherwise) I had compiled a list much as yours of what I had tried. I undid everything. I put the boat into the water and noticed about 75% of my interference was gone. Put it back on the hoist and I had 100% of it back. The water for me killed most of that interference. From that point, each thing I tried was then tested on the water. Some better some worse. I eliminated most of the fixes because they did not fix anything or made things worse. I had almost totally eliminated all except the actual RFI (transmitted radio signals through the air). The last of my interference was solved with a couple toroid chokes on my transducer cable right at the back of my unit.
It was very frustrating! I was an electronics repair tech for 37 years before that so I was not without troubleshooting experience. There is always something new to frustrate. Good luck Bob

[bombercraw]

I saw that in your initial post. That is counter to what most of us experience. Question. Did you remove all those ground wires you installed? With as many remedies applied there are some that might in fact complicate the troubleshooting. To simplify the project perhaps go back to the way things were immediately prior to installing the new trolling motor. You said you had solved the interference(mostly). About a dozen years ago I got into a similar quandary as you have reported and I was troubleshooting with my boat on a floating hoist.(totally insulated from any ground(water or otherwise) I had compiled a list much as yours of what I had tried. I undid everything. I put the boat into the water and noticed about 75% of my interference was gone. Put it back on the hoist and I had 100% of it back. The water for me killed most of that interference. From that point, each thing I tried was then tested on the water. Some better some worse. I eliminated most of the fixes because they did not fix anything or made things worse. I had almost totally eliminated all except the actual RFI (transmitted radio signals through the air). The last of my interference was solved with a couple toroid chokes on my transducer cable right at the back of my unit.
It was very frustrating! I was an electronics repair tech for 37 years before that so I was not without troubleshooting experience. There is always something new to frustrate. Good luck Bob

Thanks Bob. I was wondering about that as well regarding the possibility of my ground wires etc., possibly causing issues while on the water instead of helping. I think that is sound advice to undo all of that and put the boat in the water and see how it looks and then trial one thing at a time to eliminate options. I remain hopeful that there is a way to solve this issue. I really want to be able to use the mega 360. And I totally agree with your comments regarding it being frustrating. There has been a time or two that I was ready to rip it all out and sell the 360 and be done with it. one thing I was wondering is if there is some type of insulating wrap that exists that a guy could put around all the cables to help avoid any RFI that might be getting picked up? With your electronics experience, do you know of anything like that? Thanks again for your advice. I'll keep trying and circle back to post results as I do. Really appreciate your suggestions.

[bobcoy]

There are but then you are putting cables together in a way that the can experience possible problems between them as well. It should not be necessary to get the problem at least minimized. Shielding is only good if all wires are separate. There are things to avoid as well. Connect nothing to your trolling power other than the motor. No grounds and even wires in close proximity( tied together) even a couple inches can make a difference. If there is a charger common to the TM batteries and other batteries there needs to be some isolation involved.(like the choke supplied with some imaging transducers). You will get it done. Hang in there.