On Tue, 2 Dec 2003 16:59:39 -0500, "Jeff Morris"
wrote:

An interesting explanation, but this isn't the image I see. They appear from
medium sized vessels (tugs, CG, etc). They are roughly a 90 degree arc of a
circle centered on my vessel, and intersecting the target. Thus, the radius
indicates range, and the position of the arc is the approximate direction.
Although I always assumed it was something "active" on the target, I'm beginning
to think it might be entirely my radar. The fact that the arc is on both sides
of the target makes me think that my transmitter is radiating small side lobes
(if that's the correct term) that precede and follow the main beam. If the
target is a large reflector, and my gain is high, that might show as the arc.

-jeff

I do see what you describe occasionally with a Raytheon SR 70. I never
have seen the other phenomenon, and I never saw this one with the
previous Furuno 1720.

I don't think it indicates an active radar on the target, because I
have had it happen with big rocks. It usually goes away pretty soon.




Rodney Myrvaagnes J36 Gjo/a

"That idiot Leibniz, who wants to teach me about the infinitesimally small! Has he therefore forgotten that I am the wife of Frederick I? How can he imagine that I am unacquainted with my own husband?"