DFFI using SS264N pair 1000kw transducers



I have read a few posts that seem to relate to my problem yet seem to differ slightly. The problem that is the same is I lose bottom readings at speed.

The transducers are installed 22" forward from the transom and about 20" off the centerline. There's no thru hulls in front of them and they're inside the lifting strakes and from what I can see when looking at the water at speed it's clean coming out from under the boat in these area's. The ducers have a nice clean fit to the bottom of the boat.

I just last week realized that when I installed the DFF1 I failed to set it for 1kw so I had only been putting out 600kw as I understand the manual. I set dip switch 1 on the circuit board to 1 and took the boat out for a test run. The result was less than satisfying. Although it seems to work a little better I'm still losing bottom at speed. The digital readout blinks at crazy depths and the sounder range goes from a few hundred down to several thousand. When running these tests I'm in 150 to 600 ft of water.

Is there something I need to reset? Should I do a master reset?

The thing that's driving me nuts is that the transducer location works with other sounders such as Garmin etc. The boat I have is a Pursuit and the dealer sells and installs Garmin. I installed my ducers in the same location they install them. They get readings at speed and I get don't. So I'm stumped. Hopefully someone can shed some light.
Thank you for your question. It's hard to comment without seeing a screen shot of your sounder. Having said that there are a couple things to look for. First, how is the sounders performance in the 2-3 knot range, is the bottom nice and solid? If so, when the boat gains speed does the bottom go from a deep red to orange and yellows or does the bottom return stay deep red but have gap in the returns? What are you using the DFF1 with, 3D or VX2?

Thanks for the reply Snips. I have a very nice and solid reading at trolling speeds. I'm using the DFF1 with a 3D MFD12 both of which were purchased and installed in July of last year. If my memory serves me correct the bottom stays red but has gaps and keeps jumping the depth scale all over the place. The digital readout for example might say 420 ft when I know we're over 600 ft for example. In shallow water of say less than 80' the reading will be solid red but a very thin line instead of thick. Does that help answer your questions?

I can get some screen shots the next time I go out.
Gaps in the bottom usually means that bubbles are passing over the face of the transducer.
Below is a screen shot of what it can look like. One sign that I look for is that turbulence will (in most cases) affect the lower frequency first. If you can post a few screen shots that would help.



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I finally got out in boat and was able to get the following screen shots:

This first one is at about 8 to 10 knots


These are then the shots when cruising at speed:






The last few shows the sounder searching for bottom and were taken when the boat was over 400 to 500 feet of water.

So based on this would the conclusion be that I have air bubbles passing over the transducers?