The Sonar shows two bottoms..

[viktor_89]

Hi, my problems is that the Sonar (Humminbird wide Panorama) shows one bottom at 0,6meters depth (no matter what the real depth is). Below this false bottom, the real bottom is visible at the display but you cannot see the depth.

I got an inboard transducer, but when I tested the Sonar I held the transducer outside the boat into the water so it should not be any problems with air between the transducer and the water or similar.

Any ideas of what can be wrong?

Thanks in advance
/Viktor

 

[Beefer]

Re: The Sonar shows two bottoms..

In the sonar settings menu, there are adjustments you can make to eliminate the 'false bottom', or surface chatter. Change (lower) the sensitivity on the surface chatter, and you should be good to go.

 

[viktor_89]

Re: The Sonar shows two bottoms..

I have now tested to change the sensitivity to all possible modes without any good resluts Is there any special senstivity setting for surface chatter or did you mean the "usual" sensitivity? By the way, the transducer is now mounted inside the boat.

 

[dingbat]

Re: The Sonar shows two bottoms..

By the way, the transducer is now mounted inside the boat.

Sounds like your trying to shoot thru a double walled hull.

 

[viktor_89]

Re: The Sonar shows two bottoms..

Before i mounted it in the boat I tried to hold the transducer straight into the water but with same result, so I don't think that's the problem:/ Also if that should be the problem the real bottom sholdn't be visible, right?

 

[John_S]

Re: The Sonar shows two bottoms..

That unit is old and uses a multi element transducer. I believe it has two side angled 455khz elements along with a down facing 200khz one. Through hull peformace would be problematic for the side ones, even with the right type of hull. I would mount on transom. What does your beam diagnostic screen show?

 

[viktor_89]

Re: The Sonar shows two bottoms..

That unit is old and uses a multi element transducer. I believe it has two side angled 455khz elements along with a down facing 200khz one. Through hull peformace would be problematic for the side ones, even with the right type of hull. I would mount on transom. What does your beam diagnostic screen show?

The beam diagnostics says:
Left: 0 (depth 0.6) Right: 0 (depth 0.6) Center:26 (depth 0.6)

I dont know what these 0 0 26 means, do you?

I had prefered to mount on the transom but since the transducer got no monts for that, it becomes a bit difficult. But since i tried to hold it into the water beside the boat whit same result, it would not help to mount on the transom, right?

 

[John_S]

Re: The Sonar shows two bottoms..

The beam diagnostics says:
Left: 0 (depth 0.6) Right: 0 (depth 0.6) Center:26 (depth 0.6)

I dont know what these 0 0 26 means, do you?

I had prefered to mount on the transom but since the transducer got no monts for that, it becomes a bit difficult. But since i tried to hold it into the water beside the boat whit same result, it would not help to mount on the transom, right?

Assuming those numbers are coming from the amplitude readout, it says you are receiving nothing on the left and right, and very low on the center. That would be an indication of a bad thru hull location/install. If you are absolutly sure that you had the same results (on that diag) when it was off the transom and perpendicular, that basicly leaves defective h/w.

Do you know for sure that have the correct transducer? How many pins are in the connector end?

You can buy the mounting h/w seperatly, but might be harder in Sweden.

Manual: http://store.humminbird.cust.shopatron.com/media/document/widepanorama.pdf

 

[viktor_89]

Re: The Sonar shows two bottoms..

h/w?

The result from the diagnostik I wrote was tested with the boat on trailer. It looks the same on the display (besides the real bottom) as in the water so I assumed it wouldn't matter. But I can check the result with the boat in water tomorrow. I can also add some pictures on the screen and the transducer.

I think it shold be the right transducer. Some times when I held the transducer into the water the sonar worked correctly but only for som seconds, then it showed 0.6 and so on..

 

[John_S]

Re: The Sonar shows two bottoms..

h/w?

The result from the diagnostik I wrote was tested with the boat on trailer. It looks the same on the display (besides the real bottom) as in the water so I assumed it wouldn't matter. But I can check the result with the boat in water tomorrow. I can also add some pictures on the screen and the transducer.

I think it shold be the right transducer. Some times when I held the transducer into the water the sonar worked correctly but only for som seconds, then it showed 0.6 and so on..

No, you don't want the results from on the trailer. Provide results from on the water with estimate of actual depth and bottom type. Remove the unit from the tilt/swivel mount and draw a diagram of the pin arrangement for the transducer plug. It is sort of "house" shaped and the left most connector.

If you are getting those same results on the next water test, try moving the wire near the transducer, and see if you get any change on diagnostic display. That is a common place they break, but in most cases, not repairable.

H/W = hardware

 

[viktor_89]

Re: The Sonar shows two bottoms..

Today I looked in the diagnostics with the boat in the water. It was the same exept from 24 insted of 26 on the center. The real bottom depth seemed to meet that showed on the sonar pretty good but often it was a very weak signal. (And of course I couldn't read the depth in numbers sice it only shows 0.6..

This is how the connector from the transducer looks like:

http://www.garaget.org/?car=76095&image=2367180

Do you think there can be loose connection on the cable near the transducer?

 

[John_S]

Re: The Sonar shows two bottoms..

Today I looked in the diagnostics with the boat in the water. It was the same exept from 24 insted of 26 on the center. The real bottom depth seemed to meet that showed on the sonar pretty good but often it was a very weak signal. (And of course I couldn't read the depth in numbers sice it only shows 0.6..

This is how the connector from the transducer looks like:

http://www.garaget.org/?car=76095&image=2367180


That is the correct transducer. Make sure it is flush with the top of the connector block and supported by the metal bracket.



Do you think there can be loose connection on the cable near the transducer?

Yes, given your comment it worked mommentarily when you were hanging it over the side.

Wiggle the cable around while monitoring the diag screen, if you see a big change, (amplitude or bottom) that may be it.

Otherwise, I'd pull it out the boat and retest it in the water. If you get the same results, its not a hull/mounting issue. Transducer or the unit.

 

[viktor_89]

Re: The Sonar shows two bottoms..

Okej, I will try to wiggle the cable. Probably that's the problem I think, since I tried to hold it straight into the water several times and it worked mommentarily as you said. Hopefully I can find a location for the cable that works and strap it there.

I'll post the outcome of the "wiggle test". Thanks alot for the help!

 

[John_S]

Re: The Sonar shows two bottoms..

Okej, I will try to wiggle the cable. Probably that's the problem I think, since I tried to hold it straight into the water several times and it worked mommentarily as you said. Hopefully I can find a location for the cable that works and strap it there.

I'll post the outcome of the "wiggle test". Thanks alot for the help!

When you are there, also put your ear as close to the transducer as possible. If you hear a clicking noise, at least one of the three elements are working.

If wire or wires are broke, very unlikely to be able to find and keep that "perfect" position. They tend to break right at the entry point to the transducer. No length to splice back together, either. I still think there is a good shot that it is your hull, especially if you hear a clicking noise.