[CA] Transducer Problem?

[bonzoid]

Hi, I re-positioned my Dragonfly transducer in an attempt to try to keep the readings at speed. They drop out as I get up on plane. In making the change I now get no reading at all. Blue Screen on sonar and black on down vision. I do get a temperature reading and the GPS appears to be working. Any help would be appreciated

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum bonzoid,

Please click here to view a FAQ addressing loss of depth when operating on plane. It sounds as though you may be on the right path to addressing the issue by relocating the transducer.
Would it be possible to have you attach some photos of the transducer's instalaltion which may aid in identifying:
- it's mounting height with respect to the hull's bottom
- it's location with respect to any lifting strakes, steps, thru-hulls, steps, or other features of the hull
- it's location with respect to the lower units, running gear, trim tabs, or other transducers.
Would it be possible for you to attach a photo of the Dragonfly display's screen when the problem is observed? Finally, when this problem is observed, is the depth of the water at least 3' beneath the transducer, but not greater than 600'?

[bonzoid]

Chuck, I attached the images you asked for in hopes that it helps. My concern was for the screens not reacting like they have in the past with the boat on the trailer. I also notice a very slight flickering of the screen. I'm thinking a possible power or mounting issue with the unit?

The transducer was close to the spray deflector of my jet motor. Moving it put it near a "rib" on the opposite side. You can see where it was to where it is now.

[bonzoid]

The unit is working, but I need to get it on the water to test.

[Chuck - Raymarine - Moderator]

bonzoid,

The transducer appears to have been installed too low and appears to have been installed very close to a fore-aft strake ... the latter will most certainly expose the transducer to an aerated flow of water.

[joe-al]

I have an aluminum Ranger RT188 bass fishing boat with a Dragonfly 7 Pro fishfinder installed. I would like some assistance in determining the correct location to mount the transducer. I have good depth indication at speeds less than about 6 mph, but above that i get a blank/snowy screen with no bottom and no digital depth indication. I have attached some pictures of the current location of the transducer and the boat transom. The 1702.PDF file has some notes about the bottom of the hull where the transducer is now located; the anti-porpoising angle piece is about 1/2 in. high and welded to the hull, and the transducer is directly in front of it. I know i need to move the transducer away from its current location, i just want to make sure i don't end up moving it more than once. If you could provide some suggestions on a better (best) location, it would be most appreciated.

[Chuck - Raymarine - Moderator]

Joe,

Please click here to view a FAQ addressing this subject. Unfortunately, while most power driven hulls are quite satisfactory for transom mounted transducers, those having hull features which can cause aeration such as shown within the referenced FAQ (ex. the anti-porpoising angle stock welded to the bottom of the hull), can pose a challenge or impossible conditions for transducers mounted aft of such features or thru-hulls. You may want to consider installing a transducer mounting plate to the hull in the area between the inboard edge of the anti-porpoising angle stock and the inboard strake. The transducer may then be mounted half way between these two hull features.

[SteveME]

Got a similar issue with a new RV-100 transducer recently installed. At speeds of 12kts and above (not the same speed every time) I lose depth. Should I start troubleshooting with location or electrical interference?
Also, can the transducer be painted with an antifouling paint?

Thanks

[Chuck - Raymarine - Moderator]

Steve,

Please click here to view a FAQ addressing this subject. This problem is most commonly caused by the transducer's mounting location with respect to hull features which cause the transducer to be exposed to aerated water.

While Raymarine has not made any specific recommendations for anti-fouling paints for RealVision transducers, it is recognized that marine growth may necessitate the use of anti-fouling paints. Like the recommendations for other fishfinder transducers, it is recommended that a water based anti-fouling paints which do not contain metals (ex. copper, etc.) be used for such purposes.

[joe-al]

I moved the xducer to between the strake and the anti-porpoising angle piece, had it level with the hull bottom, above the hull, below the hull, tilted up and down in each location. the best i've gotten is depth readings at between 20 and 25 mph, and that is not very repeatable. I was advised by the merchant where i purchased it to move it outside the last strake to the right of the anti-p angle; i did that and had similar results at each height i tried.