Eratic Depth Sounder

[BalmainBug]

My Nasa target depth sounder works (pretty much) beautifully when in the Marina and when under sail, but as soon as I turn the engine on, it goes ballistic, giving readings that are way way out.

I presume that this is some sort of electrical interference in the power supply. Is there some sort of suppressor I can hook in somewhere, and where would it need to be connected.

Any help gratefully received.

Thanks

Mark

<hr width=100% size=1>

 

[Metabarca]

Does the cable run close to the engine or any of its cabling (alternator cables etc.)? If so, the problem might very well be here rather than one of power supply. If you can, try re-routing the cable away from these and see it that cures it.

<hr width=100% size=1><A target="_blank" HREF=http://www.comoy.com/saillinks.html>http://www.comoy.com/saillinks.html</A>

 

[summerwind]

You might want to look for a loose connection somewhere in the feed. It could be that vibration is causing your problem when engine is running under load.

<hr width=100% size=1>

 

[arran]

If you dont get the problem in the marina with the engine ticking over then it could well be associated with The Sensitivity Threshold.

To change the sensitivity you need to change the variable sweep gain (see instruction manual). The gain is factory set to 0.0 Meters - try increasing it.

It is possible that some extra underwater turbulence is created when you are motoring. Worth a try if you havn'e already given this a go.

<hr width=100% size=1>

 

[rivalranger]

I have the same problem with my NASA Target unit.

With the engine on (moving or not) readings are random. With the engine off no problem. Adjusting the sensitivity makes no difference. Does any one have a solution ? Or can anyone recommend a good replacement option ? Are the clipper units any better ?

<hr width=100% size=1>

 

[NigeCh]

NASA Clipper - Exactly the opposite problem

The NASA Clipper (lurid red back(???)-lighting) works fine under all conditions except in a marina when the engine is gear and the prop turning. The transducer is in the cut-away forefoot and the prop is at the stern. I've tried all combinations of timing as set out in their equally poor manual .... Marina depth 4m ... Shallow alarm set for 1.5m under transducer. Start engine ... as soon as I engage gear the alarm sounds. Once I get out of the marina the alarm and the screen start behaving normally.

I'm saving up to buy a Raymarine depth sounder as the backlighting will match the nice pale green of the Furuno Navtex/GPS repeater.

<hr width=100% size=1>

 

[gjgm]

Re: rivalranger

go for a garmin 100 fishfinder, about £90. So called because of all those USofA huntin and fishing folk,,, depth sounder doesnt have same panache ,does it. You simply epoxy the transducer on the inside of (grp) hull, and wire it up. I wouldnt bother mounting it externally. You can set it for numericals if you prefer, but the chart of the sea bed is amazing.. you can see th bed sloping right up under you ! And you can offest for the keel, so you read clearance if you prefer. You can (sort of) identify the type of seabed ,rock/mud etc, and even set it to show the fish if you want. Who would want just a depthsounder...!

<hr width=100% size=1>