Thread: RF Interference

OK, I haven't contacted them. The unit is a used 798c si. The one I purchased new is a 798ci si. The internal is at the console and the external is at the bow near the TM. My internal is out of warranty at this point so I wasn't sure they would help? I'll send an email and see what they say.

Yes they will help anyways AZ.
Calling them will produce better results than an e-mail.

Thanks again Greg. I didn't even realize that I could call. I talked to a nice gentleman by the name of Nagee. He is sending me a ferrite ring and instructions. He said if it doesn't work then to call back. I tell you what. Not enough companies have customer service like Humminbird does! Thanks again. I'll post back after I get it and try it.

Well, I finally got the boat out yesterday. The ferrite ring seems to have done the trick! There was no interference like what I was seeing before. There were some minor things but I am not sure what they were so a little more time with it and I should know for sure but I am amazed at the difference in clarity! Such a simple fix :D

I was experiencing terrible RF interference between my Terrova with US2 and two different greyscale HB units-a 718 and a 570. I ran #6 wire to the TM and had it mounted as far away from my sonar cables as possible. I added the HB choke on the recommendation of the HB customer care center-no go. I also purchased 4 additional ferrite cores and placed them in series on the HB power cord as close to the unit as possible-no go. I still had interference issues that made the unit useless most of the time on the water, as all but the top 5-10 feet of water were completely blacked out. I was about to sell the Terrova on Craislist and deciced to try one more thing. I installed a Lowrance x135 unit up front and connected it to the US2 and no interference. I have fished it for the last 2 months from water depths of 3'-88' with no RF interference whatsoever.

I'm not making this out to be a HB vs Lowrance thread as I have always been a dedicated HB customer and have an 898 on the console. I just wanted to give others hope and explain the way that I ultimately got rid of the interference and still get to use the awesome features of the Terrova.

597 di goes crazy when I touch TM workers great on 100 percent . I have it mounted on my maxxum 80 variable speed. What good place to start to fix this. It is hook to start batt

I would start by making sure that the software in your unit is up-to-date (version 6.090) and if it is, call the Humminbird Customer Resource folks at 1-800-633-1468.

Originally Posted by Hunterjt

597 di goes crazy when I touch TM workers great on 100 percent . I have it mounted on my maxxum 80 variable speed. What good place to start to fix this. It is hook to start batt

Same problem but what worked for me was a couple of RF chokes on the Power Cord for the finder and re routing the transducer cable pictured below. Good Luck.