[CA] [CA11] Odd interference on axiom units

[Farmhand]

I recently swapped out a network of a and es series units for axioms. Currently running 3. One is hooked to a through hull 50/200 transducer. One is hooked to a rv transom Mount transducer , 1 is just networked in through a network switch. Also running an ev 200 , vhf radios , fusion stereo , and p70r. The only thing I swapped out were the multi function displays and the 1 rv transducer. The system runs great, but I am getting some interference I never had with my other units. They ran extremely clear. These have interference that is occasionally worse, sometimes better. I have turned everything off and on to try and isolate, and checked the proximity of the cables with other electronics but can’t sort it out. Could the drain wire be the cause? I think my mechanic ran them to a negative bus. Your help would be much appreciated. Thanks

Farmhand

I can’t get an attachment to upload for some reason. Will try again later, but it is thin vertical lines. Sometimes I barely see them. Sometimes they are really prominate.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Farmhand,

Regarding the drain leads/terminals of Raymarine products, please click here to view a FAQ addressing this subject. Regarding the interference issue, while I understood your troubleshooting to indicate that the problem could be duplicated with everything OFF, did this include the vessel's engines? If not, please re-test with the engines off. With respect to the noise observed, is it only visible when viewing the Fishfinder application? If so, please use the MFD's Capture Screen Image feature to save a copy of the screen's image (when exhibiting the reported issue) to a microSD memory card within the MFD's memory card reader. The saved PNG file may then be attached to your response for further analysis.

[Farmhand]

Thanks Chuck,
I have narrowed it down but grabbed th wrong card lol. The offending unit is my p79 through hull connected to the axiom by adaptor cables. Just not sure if it’s the cable, adaptor, or transducer. The interference is present weather the engine is running or not. It shows up regardless of weather I’m running the 50/200 Sonar or chirp sonar. I don’t seem to notice it on down or side imaging. Do both transducers ping regardless of which one is selected? Is crosstalk a possibility? It only shows up on the sonar pages, not on navigation or anything else. And it immediately stops if I turn off the unit connected to the p79..any thoughts.

Thanks again
Wade

[Chuck - Raymarine - Moderator]

Wade,

While some degree of noise would not be uncommon, it is typically not significant and may be eliminated if the MFD is operating with the latest available LightHouse 3 software (v3.5.40 at the time of this response). By selecting Dual Channel Ping Mode (MENU->SETTINGS->SOUNDER->DUAL CHANNEL PING MODE) when using the Sonar channel, the reported noise may be cleared from the high CHIRP Sonar imagery produced by the RV transducer.

[Farmhand]

Hi Chuck,

Ok I have it completely narrowed down to crosstalk. If I disable pings on either transducer the interference goes away, so per your last response, should I enable dual channel ping mode on both transducers? Are there other fixes to try? Thanks again

[Chuck - Raymarine - Moderator]

Wade,

Installation of a 600W 50kHz/200kHz transducer in addition to the RV transducer would typically be recommended for vessels which reported being
- unable to hold bottom at planning speeds, and
- the problem persisted after dropping the tail of the RV transducer a notch or two below the setting which would make it parallel to the hull's bottom
In such cases, the 50kHz or 200kHz fishfinder channel would be monitored when operated at planing speeds. When not needed, then the 50kHz and/or 200kHz ping may be disabled.

Contrary to my prior response, Dual Channel Ping Mode is a feature of Axiom Pro RVX MFDs, not of Axiom RV MFDs and accordingly would not be applicable to an Axiom RV MFD. Would it be possible for you to attach some screen captures (use the option provided by the MFD's Shortcuts menu) showing the interference which you are reporting? How close to one another (linear distance) are the transducers? Has excess cables for these transducers been loosely (6" minimum bend radius) coiled rather than tightly bundled. Please additionally ensure that your MFD has been updated with v3.5.40 software.

[Farmhand]

Thanks again Chuck. I figured out that dual ping mode was not an option lol. I have been doing what you suggested and running 200kz on plane. My cables are all loosely coiled , I have upped the interference rejection and it may have helped. The vertical lines are maybe often enough to see 4 to 5 across the screen at any time. Forgot my card again. I’m feeling like it’s something I may have to deal with. I don’t get any interference on the 50kz which is what I use to monitor my downrigger [censored]. If I run 50 and chirp I should be good correct?

[Chuck - Raymarine - Moderator]

Wade,

Q. If I run 50 and chirp I should be good correct?
A. Yes. Unlike 50kHz, 200kHz is within the CHIRP frequency band of the RV, DownVision, CPT-S transducers, SideVision.