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Bruce in alaska Bruce in alaska is offline
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First recorded activity by BoatBanter: Dec 2007
Posts: 153
Default Microwave leak detector - active radar reflectors

In article ,
larry wrote:

John Navas wrote in
:

Marine radars have a limited vertical beam width, and the transponder
should be mounted above or below that vertical pattern. See the
Handbook:


WRONG! Geez, John....

Marine radars have limited HORIZONTAL beamwidth so you can see 3 targets
kinda close together as 3 targets, not 1 blob. They have WIDE VERTICAL
beamwidth so they are pointing at the horizon EVEN WHEN THE BOAT IS HEELED
OVER OR ROLLING!

If they had narrow vertical beamwidth, the only time you'd see the target
is in flat water or at the marina dock!


"Limited" is such a nondescript word. It really doesn't define what
either of you are trying to say. Marine Radar Antennas, typically have a
25 Degree Vertical Beamwidth, Now to some that may be "Limited", (25°
as opposed to 360°) but when compared to a Marine Radars Horizontal
Beamwidth, (Typically 2° to 6°) it is not "Limited" at all. John's
Point, was that the Radar Transponder MUST be mounted Clearly OUTSIDE
the Vertical Beamwidth of the Onboard Radar, so as to not be triggered
by the operation of the onboard Radar. This is correct.

Bruce in alaska

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Bruce in alaska
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