Could comeone point me in the right direction????
I have a Lowrance LMS320 and am having trouble picking up the bottom when in water deeper than 30m. The unit works fine a speed and when at rest in anything under 30m.
I was at the 36's saturday in about 67m and the bottom was showing as just dots(i don't have a pic) as soon as I started the motor it would loose the bottom alltogether and just flash the depth. I have turned off all auto settings and still have this problem. It's driving me nuts. The only thing I didn't try was the depth range and also the noise reduction but I thought that noise would be showing at all depths.
Could anyone help?
Cheers
Justin
Justin
I started a new thread on this because I thought it was a bit too specific for the sounder post.
I have been going through the same issue with my Eagle Seacharter 480DF.
Having gone through some trial and error myself, this is what I would do.
Before you do anything you need to be sure your sounder output is OK.
First, de-select auto depth control and set the depth manually to say 2 to 3 times the depth you are in. Do this in water say 5 mts deep.
Then turn off the auto sensitivity control.
Also turn off both the noise rejection and surface clarity. (These two features effectively reduce the receiver sensitivity and at this stage you need maximum sensitivity.)
Set the grayline/colourline setting to 0%.
Set the manual sensitivity to a low setting say 10%, now progressively wind the manual sensitivity setting up.
If the sounder power is anything like it should be, as you increase sensitivity you should first see a single return for the bottom. As you increase sensitivity you should see returns at multiples of the bottom depth on the screen.
For example lets say your depth is 5 mts and you have manually set the range to 25 mts, you should see multiple echoes at 5, 10, 15, 20, 25 mts. All echoes getting progressively weaker. You might not get them all, but you should get some of them. Certainly more than one.
If this is succesful, try it again in deeper water.
If you still get mutiple echoes then I think you can say that your sounder power and receiver sensitivity is OK.
However, from what you describe, I suspect you will find that you are struggling to get multiple echoes. Either your transmitter is low power, receiver low sensitivity, or your transducer is stuffed.
What you need to do then is to eliminate by substitution. Find someone with the same transducer and arrange to meet up and do a test.
What transducer do you have?
In my case I believe it was the transducer causing the problem, but to complicate matters, I also had an issue with the head unit so in the end they both went back to Lowrance in the States. The repaired/replaced units are presently on the way back to me, so I have to wait to see what they say was the problem.
Hope this helps
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