Clipper Duet, is it me !

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tsekul

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Hi There,

I have a Nasa clipper duet, log and depth. I have tried to set the depth to water line but it does not allow me to enter a negative figure in the keel offset option. It must be possible to do it surely, but I can't figure it out, and I have the instruction booklet............is it me !

Thanks in advance
Tim
 
The offset is the distance down from the transducer to the bottom of the keel. I can't see how this would be negative as it would mean that the keel is higher than the transducer.
 
I have Clipper Duet and as far as I am aware you can only have depth below transducer or depth below keel. I have mine set on depth below keel and have the alarm set at 0.5m. Once you get used to it it is no problem. Check with NASA but I believe you can have depth below waterline with the standalone Clipper depth instrument.

Dave.
 
ghostlymoron said:
The offset is the distance down from the transducer to the bottom of the keel. I can't see how this would be negative as it would mean that the keel is higher than the transducer.
Click to expand...

Agreed. With my Raymarine system, keel bottom is negative offset and waterline is positive offset. OP should be able to set a negative offset but for waterline he needs to go positive.

Richard
 
ghostlymoron said:
The offset is the distance down from the transducer to the bottom of the keel. I can't see how this would be negative as it would mean that the keel is higher than the transducer.
Click to expand...

Because depth below keel is LESS than depth below transducer so a negative offset is required. (if logic applies ?)

Similarly a positive offset for depth below waterline.

If manufactures have the opposite offset for depth then they have some crazy logic !
 
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theoldsalt said:
Because depth below keel is LESS than depth below transducer so a negative offset is required. (if logic applies ?)

Similarly a positive offset for depth below waterline.

If manufactures have the opposite offset for depth then they have some crazy logic !
Click to expand...


The OP is trying to set depth to waterline and is trying to set a negative offset in this context. I think that ghostlymoron is saying he can't see how this can be a negative offset.

Richard
 
Thanks guys looks like I will have to make do with below keel.
Positive, negative what ever it only adjusts one way.

Bit stupid really as there must be enough people out there that prefer depth from water line,
 
tsekul said:
Thanks guys looks like I will have to make do with below keel.
Positive, negative what ever it only adjusts one way.

Bit stupid really as there must be enough people out there that prefer depth from water line,
Click to expand...

I have never been able to understand the preference of depth below waterline. Depth below keel is what indicates whether you are about to go aground or not. Added to which the draft of a vessel can vary due to many factors.
 
I can't understand the desire for depth below waterline. Surely all you need to know is how much water there is under the keel? Displaying depth below waterline requires constant mental arithmetic.

However, I have a friend whose plotter displays depth in metres, but whose depth display is always in feet, because "that's what I'm comfortable with".
 
MM5AHO said:
an alarm set at 0.5m doesn't give much warning. I have mine at 3m and I wonder if that's too little?
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1m for me and in the tidal waters I sail in the alarm regularly goes off as we creep back into the tidal-rode berth. Anything more than that and people would start throwing things at it to shut it up!

Depth from waterline makes little sense to me, I like to know what I have beneath my keel without doing any maths.
 
pvb said:
I can't understand the desire for depth below waterline. Surely all you need to know is how much water there is under the keel? Displaying depth below waterline requires constant mental arithmetic.

However, I have a friend whose plotter displays depth in metres, but whose depth display is always in feet, because "that's what I'm comfortable with".
Click to expand...

My Garmin plotter / sounder (451S) only has one selection for unit type. If I want the speed and distances to be shown in knots and nautical miles the depth is shown in feet. I could have the depth in meters (which I prefer) but I'd have the distances in Knots and speed in kmh.

Mind you, it's cured me from telling marinas etc that the boat 31ft long, 1.4m deep.
 
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+1 for having depth shown as below keel. I discounted the depth from waterline (charted depth?) in my earlier post as i couldn't see the use for it but it does enable you to compare actual with charted i suppose. My guru advises mounting transducer as far forrard as possible to give longest warning of disaster!
 
I checked with NASA a while back - you can't set from waterline.
I wanted to set from waterline because it was a lift keel boat so depth below keel was variable.
I still prefer to set from waterline (I can with ST60).
Setting below keel is a bit like setting your speedometer to show how much above the speed limit you are!
 
Plevier said:
I still prefer to set from waterline (I can with ST60).
Setting below keel is a bit like setting your speedometer to show how much above the speed limit you are!
Click to expand...

Snap. Actual depth is more logical when looking at charts & tide tables. I don't need to make any conscious conversion from depth of water to depth below my keel.
 
SteveTibbetts said:
My Garmin plotter / sounder (451S) only has one selection for unit type. If I want the speed and distances to be shown in knots and nautical miles the depth is shown in feet. I could have the depth in meters (which I prefer) but I'd have the distances in Knots and speed in kmh.

Mind you, it's cured me from telling marinas etc that the boat 31ft long, 1.4m deep.
Click to expand...

I think you'll find that your Garmin 451 has a "Custom" settings facility, allowing you to choose the units you want.
 
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