T&T: Anchoring and anchor watch

[Jim Ague]

> Help me understand why it is a "problem" for the GPS to not be over the
> anchor?  ...  Why not use the location
> where the boat comes TO REST after anchoring?

Maybe the phrase "TO REST" is where the confusion is coming from.

If you only anchor for lunch or evening cocktails for half an hour, the boat 
probably comes to rest, and stays there. But if you anchor overnight, 
there's a chance that the wind will clock around, or if in a tidal area the 
current will change 180 degrees. Now instead of being 150 feet in one 
direction of the anchor, you're 150 feet in the opposite direction, 
presuming the anchor remained at rest. Or a football field away from where 
you started!!

So the anchor watch we want is a circle with its center at the point where 
the anchor lies and its radius equal to how much rode we paid out. If the 
GPS thinks we left this circle, then the anchor alarm goes off and 
presumably the anchor drug.

-- Jim Ague