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Robert Miles Robert Miles is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 13
Default Radar for sailboats

First see what you need:
If you want it for tight waters a radome might not have sufficient
resolution, as this is dependent on the lenght of the antenna.

see this post (lenghty
discussion of all the aspects under the title Koden radars:

radio beam width [degrees] = 2.1 / Antenna Length [m]
ie a 40 cm radome gives 5.6°
a 65 cm cm (2') radome gives 3.2°
a 90 cm (3') open array gives 2.3°
a 120 cm (4') open array gives 1.8°
a 180 cm (6')open array gives 1.2°

Then: eg 4kW is the peak power.

As for manufacturers apart from Furuno there is now Koden it seems, and
have a look at Simrad DX-60 if you want a radome.


Thanks for the posts.. to expand a little, and bemoan the fact that I can't
get what I want! ( do small sail boat users feature in the designers mind at
all?)

Most times I use radar for collision avoidance and sometimes to identify
Racons.
The most important factors I look for are low power consumption, and a small
radome to minimise impact on the sail ( Friction when tacking) and CoG.
As some folk have said, the pulse power can be higher but average power kept
low. I guess that there is a trade off with a lower pulse repetition
frequency to reduce average power.. or is the rotational frequency reduced
to compensate.. ?
The sales blurb has a lot of attention on beam width and sexy graphics and
colours for the display but less on usability and installability in small
yachts?

I guess I can get an 18" radome and 2Kw from a number of suppliers..but I
quite liked the 1.5Kw 12" Radome of the JRC 1000 - 30W average power
consumption .. 25% - 40% saving on power!

Did the job for me! Size isn't everything..

Just have to compromise.. again..

Regards

Bob