Furuno TZtouch3 12F interference

[Nick]

Hello everyone,

I would appreciate any advice if possible. TZtouch3 12F with Airmar B275LHW transducer is installed on board. Everything is connected with the original cable and M&M adapter. Everything worked fine for about two months, but now, there are huge interference when the engine is running (alternator). The boat engine is new. Nothing was changed or added to the boat. I tried with a completely isolated battery, but the same thing, no difference. I tried grounding the device to the minus of the power supply, that didn't help either. I've tried disconnecting all the peripherals, but it's obvious that the interference is coming through the transducer. I also put ferrite beads, but no results were achieved!? After all, I don't understand what else I could do?

Thanks
Nick

 

[Johnny Electron]

If related to the engine being on and running it is likely to be a bad diode in the alternator at least that is what we see on boats that have ran into this problem. Grounds are important but ultimately getting rid of the noise source is the best method to resolution.

 

[Nick]

Thank You,

I have the same thoughts but I'm a little confused about the boat engine being new (no more than 50 hours)!? I will have a chance to try it with another TZtouch3 device. I just want to be sure.

Thank you for your reply
Nick

 

[DannyAtSowilo]

"Tried with a isolated battery" : Do you mean you disconnected house battery. So alternator only charge start battery?
If so it is strange.

Still it sound like alternator problem. I would remove the drive belt of the alternator to see if the problem goes away. If so you know for sure.

 

[Keta]

Nick what engine do you have? Does the noise increase as you go up in rpm's? I have a Volvo D6. Same transducer as you but unfortunately installed right next to the alternator. The noise I have looks like I have too much gain...IE it doesn't look like cavitation noise (air bubbles). Never lose the bottom. I have to drop the gain settings when running versus fishing. I've done the same steps as you. Also added a Newmar filter into the system...helped a bit but not much. Added a Dynaplate to the bottom of the boat to ground to. I don't think that helped much but it's there.

I've kind of given up so have been operating with a decreased amount of gain when running and then cranking it up when fishing/trolling. I haven't heard about maybe a faulty diode in the alternator thus the reason I asked what your engine was. My problem has been there from the start. I guess it's time for me to call Volvo to see what they have to say.

Please let us know if you solve it and what was done.