Depth sounder struggling

Lucky Duck

Lucky Duck

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Following on my from my earlier issues with a sticking paddle wheel (some mclube seemed to sort that one), today the depth sounder wasn't giving any data once beyond 30m.

In the short term this isn't much of an issue when day sailing on lake Solent, however I would like to fix it.

Any thoughts on possible causes?

When messing around with the paddle wheel I could here the unit 'clicking'

Speed/depth unit is a DST200

Edit- last season it was showing up to 130m deep
 
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Only thing I can think of apart from a partial failure of the unit itself is a lack of power meaning the transmitted pulses are weaker than they should be. Check the supply to the N2k power tee?

Pete
 
+1, if it's N2K, undo and redo the tee and check for muck or verdigris, never seen such a thing though, it would affect displays and other instruments unless it's v.local to that tee, wouldn't it?
 
I had a similar problem several years ago, but worse As it only worked under about 10 metres. I vaguely recall it was something to do with the cable braided screen connection on the back of the display head. Possibly it was the screen is not supposed to be connected. When the screen was bonded/connected to the negative it induced into the sounder cable interference sourced from elsewhere in the boat electrics . The screen was acting like an antenna. It could have been that something new on the yacht caused the new interference. Maybe the cable is pinched so the screen is now touching one of the cores.
 
A number of things can reduce the range of a depth sounder. I have the same transducer. In the clear waters of the Eastern Med I sometimes see depths of over 180 metres before the depth display blanks because the water is too deep, but in murkier water it will blank out at shallower depths. Were you in particularly dirty water?, though I would still expect to be able to see depths up to about 100 metres even in the cloudier waters around parts of the UK.
Another thing that will reduce the effective range of a depth sounder is anything coating the outer surface, grease or antifoul will both cut the range, but again 30 metres is poor and suggests that all is not right with the transducer. Did you check that when it said 30 metres, that was at least approximately correct?
 
The depth data was lost when in the ship channel between the Solent forts so 30m seems realistic.

Will start with the cable connections.

Thinking about it the depth sounder has always seemed quite sensitive to air bubbles so a big dose of reverse when berthing or the prop wash from a large ship can occasionally confuse it.
 
Little Grebe said:
The depth data was lost when in the ship channel between the Solent forts so 30m seems realistic.

Will start with the cable connections.

Thinking about it the depth sounder has always seemed quite sensitive to air bubbles so a big dose of reverse when berthing or the prop wash from a large ship can occasionally confuse it.
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yes, but were you at planning speed at the time, doubt it :rolleyes:
not much you can do really, undo the tee and redo it, they do have some rubber o-rings, so nothing should be getting in.
then if you do have the plug and you're happy to get some water in, remove it, check it clean the surface and try again...

V.
 
you don't happen to have a second transducer for a fishfinder which is also on the same NMEA2000 bus, do you? I did have some issues (different values reported) when I'd turn on the fishfinder option of the garmin plotter. Was a matter of choosing which sensor data you want to show. Mind even in the Med, I sometimes get it to show up to 140-160m, other times looses the bottom at 100...

V
 
Little Grebe said:
Following on my from my earlier issues with a sticking paddle wheel (some mclube seemed to sort that one), today the depth sounder wasn't giving any data once beyond 30m.
Click to expand...
Personally, once I am over the 10 meter contour I really don't care what the depth is.
 
Sandy said:
Personally, once I am over the 10 meter contour I really don't care what the depth is.
Click to expand...

Nor me really, but if my sounder was showing signs of potentially failing, I’d want to fix it before it stopped working in shallow water as well as deep.

Last year I ignored my AIS receiver starting to lose more and more targets over several months, and then regretted it when it crapped out completely in thick fog in the shipping lanes. Radar saw us through, but it would have been extremely helpful to have had both operating in tandem.

Pete
 
prv said:
Nor me really, but if my sounder was showing signs of potentially failing, I’d want to fix it before it stopped working in shallow water as well as deep.

Last year I ignored my AIS receiver starting to lose more and more targets over several months, and then regretted it when it crapped out completely in thick fog in the shipping lanes. Radar saw us through, but it would have been extremely helpful to have had both operating in tandem.

Pete
Click to expand...
I ignore my AIS all the time. It sits down at the nav station letting the world know where we are.
 
prv said:
Nor me really, but if my sounder was showing signs of potentially failing, I’d want to fix it before it stopped working in shallow water as well as deep.

Last year I ignored my AIS receiver starting to lose more and more targets over several months, and then regretted it when it crapped out completely in thick fog in the shipping lanes. Radar saw us through, but it would have been extremely helpful to have had both operating in tandem.

Pete
Click to expand...

This, although knowing the depth can be useful in terms of navigation. The 'loss of data' alarm is a bit annoying as well.

Lodesman77 said:
How heavily has it been antifouled
since last season? Build up getting a bit too much?
Click to expand...

I put some of the 'echo' transducer a/f just before launch a fortnight ago but it was a bit stodgy so it is on my list to clean off if the problem persists.
 
Little Grebe said:
I put some of the 'echo' transducer a/f just before launch a fortnight ago but it was a bit stodgy so it is on my list to clean off if the problem persists.
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Pull it out and clean it off, and see if that does the trick. I never antifoul mine, but just pull it from time to time and clean off any growth from paddle wheel and transducer face. If you are quick pulling it and pushing the bung in you only get a pint or so of water in.
 
Little Grebe said:
Following on my from my earlier issues with a sticking paddle wheel (some mclube seemed to sort that one), today the depth sounder wasn't giving any data once beyond 30m.

In the short term this isn't much of an issue when day sailing on lake Solent, however I would like to fix it.

Any thoughts on possible causes?

When messing around with the paddle wheel I could here the unit 'clicking'

Speed/depth unit is a DST200

Edit- last season it was showing up to 130m deep
Click to expand...
That is speed, shouldn't affect depth in any way.
 
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