Running my 917c up in the bow with a Minn Kota PD with a universal transducer. I’m seeing interference on the 917c screen. It appears like electrical “noise”. Anybody have this issue and a possible fix? Thanks.
Where is the power coming from for the finder? If you are running it from the trolling motor batteries that could be it.
DT
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Where is the power coming from for the finder? If you are running it from the trolling motor batteries that could be it.
DT
Not feeding off the trolling motor batteries. I knew better and isolated the units power.
I only see the interference when the trolling motor is running. Otherwise screen is nice and clear. Actually it’s only at certain speeds of the motor. So that leads me to believe it may be a harmonic frequency from the prop. OR the motor when it hits a certain RPM.
Do you have an onboard charger? If so it maybe creating a common ground between the trolling motor and sonar batteries. This will cause interference. With the US2 you do not want a common ground with your trolling batteries. I had a similar problem with a Terrova. My Terrova actually had an internal fuse that would blow due to the common ground. I now unhook the ground from my onboard charger to the starter (sonar) battery except when I am charging, and when charging I unplug the trolling motor. This and replacing the fuse solved my problem.
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Do you have an onboard charger? If so it maybe creating a common ground between the trolling motor and sonar batteries. This will cause interference. With the US2 you do not want a common ground with your trolling batteries. I had a similar problem with a Terrova. My Terrova actually had an internal fuse that would blow due to the common ground. I now unhook the ground from my onboard charger to the starter (sonar) battery except when I am charging, and when charging I unplug the trolling motor. This and replacing the fuse solved my problem.
I have an on-board charger, however it is not charging my starting battery where the electronics are connected. Good FYI for when I upgrade to a 4 bank though. Perhaps I’ll just put in a toggle for the “common ground”. If I wire it that way.
Do you have another sonar unit running at the console?
If so you might be getting interferring sonar signals from the two units. Change the console to a different frequency while running the bow unit.
—Edit: I didn’t see the interference is only while running the trolling motor so this dual sonar interference is probably not the cause.
Ruger- I think this post might have a solution to your issue: http://www.walleyecentral.com/forums/showthread.php?t=161997
It looks like you can call Humminbird customer service and get an inline filter to solve the issue. Although this specific post is regarding a Terova I suspect it might also cover your issue.
I would still check to see if you have small fuse under the head on your PD2. My terrova has one and I know Maxum US2 do also, but I am not sure if PDs do. If it does and is blown I would guess that has something to do with your problem. I am not sure exactly what this fuse does but when it is blown it causes interference. If it is blown try replacing it, but if a blows again you have to figure out why (onboard charger in my case).
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Calling Minn Kota and/or Humminbird would be a good idea. Someone on another forum posted an email from Minn Kota which is what led me to my solution.
Yup. Get the RF kit from Johnson Outdoors. 
Ok, here is the interference. First pic is trolling motor set to “O” speed. Second is set to “2” speed. Third is set to “4” speed. Fourth is set to “6” speed. Fifth is set to “8” speed. Sixth is set to “10” speed. In the last frame you’ll see interference when I power up from 0-10, then it seems to settle down some.
Wade, are you referring to Humminbird’s TMC-1 (Trolling Motor Choke)? Thanks.
Was there a good chop,It looks like the same thing I get when the bow is bobbin! I think its a combination of the bubbles from the prop and the bow bobbin. To be honest,I never liked the us-2 much,I put a HDSI transducer on the trolling motor.I think its Much better!
You could put a quadra beam transducer there also,if you don’t have side imaging up front!
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Was there a good chop,It looks like the same thing I get when the bow is bobbin! I think its a combination of the bubbles from the prop and the bow bobbin.
I was moving forward, so it wouldn’t be bubbles from the prop. Also it was calm.
Anyone experiencing this. I installed an electrical choke, and trolling motor choke and neither seemed to help (or minimally). Then I installed the Ferite Rings and that solved the problem.
What are the Ferite Rings?
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What are the Ferrite Rings?
They are part of the interference kit. Basically doughnuts made of Ferrite. Jason may have a better explanation. Basically you wrap your transducer cable through the Ferrite Ring about 6-7 times. I assume it has something to do with isolating the weak electrical signal. The polarity of the Ferrite Ring can do that. That’s an educated guess though.
Wow, that’s crazy. Seems weird that someone would have to do such a thing.
The manufactors should have a better fix for this. Or is it needed because of some other product that is not built as well in shielding?
Wouldn’t you as well bring on issues from kind’of kinking the cable around that tight as well in the long run?
The manufacturers should have a better fix for this. Or is it needed because of some other product that is not built as well in shielding? I’m assuming this is Humminbird’s fix for a Minn Kota transducer issue. Not a 100% sure, but that seems logical to me.
Wouldn’t you as well bring on issues from kind’of kinking the cable around that tight as well in the long run?
It is a tight corner, but I don’t think it’ll be to big of an issue. It’s not like you are kinking and unkinking. It’s a 1 time deal. So far.
Also it doesn’t look as bad as you would think. I’m zoomed in pretty tight to show you the rings. They blend in pretty good.
Quote” The manufacturers should have a better fix for this. Or is it needed because of some other product that is not built as well in shielding? I’m assuming this is Humminbird’s fix for a Minn Kota transducer issue. Not a 100% sure, but that seems logical to me.”Unquote
With both being owned by the same parent company, I would think this would have been worked around.
I’m really not sure if that’s the reason for the fix. However, I can tell you that working with major corporations. Just cause there is a parent company, doesn’t mean they communicate or work together. I could be wrong about HB and MK though.
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I’m really not sure if that’s the reason for the fix. However, I can tell you that working with major corporations. Just cause there is a parent company, doesn’t mean they communicate or work together. I could be wrong about HB and MK though.
I agree with you, but I still am looking forward to them (HB and MK) doing it!
This is probably a dumb question but after having a lot of issues with my minnkota an my humminbird 798 they finally decided to sent me the trolling motor interfernce kit 2 & 3….My question is I have a 798 at the bow an a 997 on the console….I am thinking about taking the 798 an selling to a buddy…..Should i still put some of the ferrite rings on the graph on the 997 on console?? also what cord are your suppose to wrap them around? just the one you get power from?? They sent me 4 ferrite rings…..Also would it be worth putting the trolling motor choke on if I take that graph off the bow??
Thanks abunch guys….
what did we ever do without the internet!
Ok guys here is something i found this weekend my terrova (us2)is mounted on a MKA-21 Quick Release Bracket made of plastic so when mounted to my aluminum boat it is not grounded to the boat. when I use a ground wire from the frame of the minn kota (us2) to frame of boat i get different readings coming from my us2 when not in the water on my 597ci hd so the question is when mounting minn kota TM with us2 should the trolling motor be grounded to boat or not someone should check with humminbird/minn kota 
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