DIY Radar reflectors and which one is best ??

[Evadne]

An alloy mast does not show up on radar: as pointed out (Brendan I think it was) you have to reflect the signal back to the sender, so any convex surface is next to useless.

Biggest is best, yes. The same principle as radio aeriels applies: a small but clever one will efficiently reflect back a small amount of signal, whereas a large and relatively inefficient one can send back just as much. One of the best reflectors on a sailing boat is the mainsail, wet or dry. I have seen a signal appear from nowhere when a yacht changed course and gybed, putting the sail square on to the ship's radar signal.

Despite my desire for the minimum of electronics on my boat, I am seriously considering the SeaMe this year, as it gives the best return of all, albeit in X-band only, and offers the minimum windage and inconvenience. At a cost.

 

[Oldhand]

No, I'm afraid your proposed DIY radar reflector wouldn't be much good, it would scatter radar signals in all directions but the reflected signal strength would be low because of the small reflecting area presented in any one direction. I might produce a few good random "glints" but not a strong all round reflection.

The requirements to make a good radar reflector are;

1. A large presented reflecting area.
2. Even presentation of the reflecting area in the horizontal plane
3. Minimum reduction in reflecting area at +/- 30 degrees in the vertical plane.