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rhys
 
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On Mon, 14 Feb 2005 21:07:37 GMT, Dan Best
wrote:

I dissagree.
The antenna that the energy is radiating off of is much wider than the
mast, so while some of the energy is reflected and scattered, most of it
just flows right on past. The reverse happens with the reflected
energy. As a result, the targets are weaker, but should still be there.
If this were not the case, then whenever you had a mast mounted radar,
everything in a fairly wide cone behind you would be invisible and this
is obviously not the case.


Thanks to you and Otnmbrd for these answers.

On a related topic, make sure that you mount the display where it can be
seen by the helmsman. A friend of mine has it mounted where it can only
be seen at the nav station and having played radar officer calling up
instructions to the helm on a foggy night in SF Bay while dodging
freighters, I'm here to say that that's not how you want to set it up.


It would tend to "compound errors", certainly. I've installed
something on my current boat, however, that I haven't seen before. I
got a gooseneck armature from an old draftsman's flourescent light and
clamped it so that it swings into the companionway. It can be lashed
in position with shock cord, if needed, but usually the friction knobs
do the trick.

On the armature I've secured a handheld GPS on "ship's power" (a 12 V
cigarette lighter style adapter). This means I can reference the GPS
quickly without using my hands, and without it being loose in the
cockpit, without eating batteries (they go through AAs in 2-3 hours of
continuous use), without losing "satellite lock" (because they are on
all the time and in the companionway can "see" enough sky).

Other advantages are (mostly) out of the weather (a ziplock bag will
do the trick here as well).

Of course, I have a tiller, which means I am standing most of the time
by the companionway near the winches and aft of the traveller on the
cabin-top.

I wonder, however, if my "armature idea" would be useful for any
similar devices, as opposed to a "hard-mount" at the wheel? If, for
instance, you had a 15" LCD panel and a wireless mouse, the panel
could be some distance away and still be readable.

R.