I would like to see out 8 to 10 miles with the
radome mounted 20-30' up the mizzen.

Hi Bruce,

As Jeff says, your radar will not be able to pick up small targets past
your visible horizon (about 6.3 nm according to Bowditch). You will be
able to pick up big, tall contacts further out, but that's about it.

I'd stick to a 1.5 to 2 kw radar if I were you. Higher power doesn't
"burn" through anything, including fog, and I think 4 kw is over kill
for what you'll be doing. In fact at the short ranges you'll be
operating at, the higher power will probably be a disadvantage. The
RayMarine stuff looks pretty nice and has alot of nice features (like
color and MARPA (their adaptation of ARPA)). But I'd go with a small
Furuno if you can afford it or another JRC if you're on the cheap. Just
my biased opinion though. Walk around the docks and see what the
smaller commercial fisherman in your area use. They tend to only get
stuff that works, why not do the same?

Just remember, if you get too fancy a radar, chances are your attention
will be fixated on that fancy screen and not your main navigation tool:
your "Mark I Mod II Eyeballs" ;-)

Hope this helps,

Paul

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In article ,
renewontime dot com wrote:

Higher power doesn't
"burn" through anything, including fog,

Bzzzzt, wrong answer Dude, would you like to try for what is behind
Door #3??????

When was the last time, you measured Water Adsorption at 10Ghz?
Obviously, not in the last 50 years, since Xband has come into
Marine Radar use. Water Adsoption is a Significant cause of loss of
Targets, when the humidity of the air between the transmitter
and target is high. 4Kw PPP wil certainly "Burn thru" more
humid air than 2Kw PPP. One must also consider, that heavy rain,
like in squalls, will also tend to drop the siganl level of received
targets in the Xband, due to defraction of the RF by the rain droplets.

These, and other KNOWN, physical elements all play a part in
Maximum Detection Distance of a target in Marine Radar Systems.

Me one who deals with this stuff every day......

On Mon, 14 Feb 2005 21:22:32 GMT, Me wrote:

In article ,
renewontime dot com wrote:

Higher power doesn't
"burn" through anything, including fog,

Bzzzzt, wrong answer Dude, would you like to try for what is behind
Door #3??????

When was the last time, you measured Water Adsorption at 10Ghz?
Obviously, not in the last 50 years, since Xband has come into
Marine Radar use. Water Adsoption is a Significant cause of loss of
Targets, when the humidity of the air between the transmitter
Perhaps you mean 'absorption?' 'Adsorption is hardly possible for rf.



and target is high. 4Kw PPP wil certainly "Burn thru" more
humid air than 2Kw PPP. One must also consider, that heavy rain,
like in squalls, will also tend to drop the siganl level of received
targets in the Xband, due to defraction of the RF by the rain droplets.

These, and other KNOWN, physical elements all play a part in
Maximum Detection Distance of a target in Marine Radar Systems.

Me one who deals with this stuff every day......



Rodney Myrvaagnes J36 Gjo/a


Does one child rape really change Strom Thurmond's lifetime record?
For better or worse?