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Short Wave Sportfishing[_2_] Short Wave Sportfishing[_2_] is offline
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First recorded activity by BoatBanter: Mar 2008
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Default Which echo sounder is good up to (almost) zero depth?

On Mon, 09 Jun 2008 19:50:06 -0400, RLM wrote:

On Mon, 09 Jun 2008 23:31:21 +0000, Short Wave Sportfishing wrote:

On Mon, 09 Jun 2008 11:04:13 -0400, wrote:


In a sailboat, the transducer would be mounted in the hull, above the
level of the top of the keel, so you would have 4-10 feet (depending
on how deep a keel you have) of water even with the keel scraping
bottom. Sounders usually have a "keel offset" setting to compensate
and tell you how much depth remains after the keel height is
subtracted.


I understand that - I'm not clear on the whole zero depth concept.


If the water's muddy and you can see the bottom that's the zero depth
concept or just use the acronym ZDC.

The sounder is the noise the hull makes scrapping in the mud.


That's kind of my point. Zero depth implies no water. If there is no
water, why do you need a depth finder?