See Below:
"Geoffrey W. Schultz" wrote in message
7...
I have a Furuno 1621 MkII radar that I've never been happy with. At this
point I believe that the radome has basically failed and I'm planning on
replacing the entire system.

I think that I'm going to replace it with RayMarine C70 system which
provides a radar and chartplotter. This will be compatible with my
Autohelm autopilot and this will provide a redundant chartplotter.

I've been pondering the differences between a 2KW radome and a 4 KW
radome.
Based upon the litature the 2 KW unit provides 24 nm range vs 48 nm range.
This doesn't seem to really matter as the radar is only mounted about
10-12
feet above the water on a radar mast and the radar horizon to a 50' high
target is only 14+ miles. I've been told that the 4KW is very helpful in
dense fog (not applicable to the Caribbean where I spend most of my time,
but would be useful when I return to New England) or heavy rain and that
it
also provides better separation of targets.

My typical use of radar is at night where I have the range set to about 8
nm or to watch for squalls, where the extended range would be useful.

There's a huge difference in cost between the two. The 2KW unit runs
around $900 and the 4KW unit runs about $1600. Based upon my usage and
setup, is the additional cost worth it? Are there other things that I
should be thinking of?

Thanks, Geoff

Definitely go with the higher power/larger dome if it is available. Not
only more power too burn thru rain/fog but better target discrimination with
larger dome. Is that a single blip or a tug/barge? Without gong into great
detail I ma running a 10 KW on my yacht because I can afford it both
economically and from a power draw and mounting standpoint because I was
once in a situation where the rain was so heavy that I couldn't attenuate
the rain echoes without losing all targets and I was in the Straits of
Mackinaw where there were 1000 foot freighters within 1 mile of me (I knew
because I was giving security broadcasts and they were responding on the
VHF).