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TT: Radar flag was radar reflector

FM
Faure, Marin
Fri, Jun 20, 2008 5:58 PM

I just took possession of a new dry suit and the literature that came

with it boasts of new more light reflective material as well as metal
backing to make the wearer more visible to radar when on the surface.
So, considering that at most only the top of your shoulders are above
water, I guess the claim made by that company could be plausible.

I think it was Arild that made the very good point that what you see on
your radar display depends very heavily on how well the radar is set up.
I find that with our relatively new Furuno NavNet VX2 I am always
adjusting the various settings to make sure I'm not overlooking
something, particularly when I change ranges.  The VX2 has auto settings
for gain, rain, and sea clutter, but I've found that I can get much
better display detail by tuning manually than using the auto settings,
so we never use them.  With regards to the dry suit comment above, if
the water is relatively smooth, we easily pick up the crab pot buoys
that often litter Bellingham Bay.  These buoys are made of foam, but
many of them have a metal fender washer to keep the pot line from
slipping through the buoy.  And we routinely see seagulls and other
waterbirds on the display and they have no metal on them at all.  Same
thing with kayaks although there may be a bit of metal on them in the
form of hardware.  If the water is at all choppy, however, these targets
pretty much disappear or become so intermittent they are easy to
overlook.

But I think the success a person has with radar displays is mostly
dependent on their ability to tune the set, and to periodically check it
to make sure a weak return is not getting buried in noise or clutter, or
being "overpowered" by too-high a gain setting or whatever.  I did not
learn any of this intuitively.  I used several books, the best of which
is "The Radar Book" by Kevin Monahan.  If you want to know how to get
the most from your radar I highly recommend it.


C. Marin Faure
GB36-403 "La Perouse"
Bellingham, Washington

>I just took possession of a new dry suit and the literature that came with it boasts of new more light reflective material as well as metal backing to make the wearer more visible to radar when on the surface. So, considering that at most only the top of your shoulders are above water, I guess the claim made by that company could be plausible. I think it was Arild that made the very good point that what you see on your radar display depends very heavily on how well the radar is set up. I find that with our relatively new Furuno NavNet VX2 I am always adjusting the various settings to make sure I'm not overlooking something, particularly when I change ranges. The VX2 has auto settings for gain, rain, and sea clutter, but I've found that I can get much better display detail by tuning manually than using the auto settings, so we never use them. With regards to the dry suit comment above, if the water is relatively smooth, we easily pick up the crab pot buoys that often litter Bellingham Bay. These buoys are made of foam, but many of them have a metal fender washer to keep the pot line from slipping through the buoy. And we routinely see seagulls and other waterbirds on the display and they have no metal on them at all. Same thing with kayaks although there may be a bit of metal on them in the form of hardware. If the water is at all choppy, however, these targets pretty much disappear or become so intermittent they are easy to overlook. But I think the success a person has with radar displays is mostly dependent on their ability to tune the set, and to periodically check it to make sure a weak return is not getting buried in noise or clutter, or being "overpowered" by too-high a gain setting or whatever. I did not learn any of this intuitively. I used several books, the best of which is "The Radar Book" by Kevin Monahan. If you want to know how to get the most from your radar I highly recommend it. ______________________________ C. Marin Faure GB36-403 "La Perouse" Bellingham, Washington
MM
Mike Maurice
Fri, Jun 20, 2008 6:25 PM

I find that with our relatively new Furuno NavNet VX2 I am always
adjusting the various settings to make sure I'm not overlooking
something, particularly when I change ranges.  The VX2 has auto settings
for gain, rain, and sea clutter, but I've found that I can get much
better display detail by tuning manually than using the auto settings,
so we never use them.  With regards to the dry suit comment above, if

Marin,
Your conclusion about the automatic settings is quite right. I consider
the auto settings to be dangerous and avoid using them. This includes
the Raymarine stuff as well as Furuno radars.

Mike


Capt. Mike Maurice
Beaverton Oregon(Near Portland)

> I find that with our relatively new Furuno NavNet VX2 I am always > adjusting the various settings to make sure I'm not overlooking > something, particularly when I change ranges. The VX2 has auto settings > for gain, rain, and sea clutter, but I've found that I can get much > better display detail by tuning manually than using the auto settings, > so we never use them. With regards to the dry suit comment above, if Marin, Your conclusion about the automatic settings is quite right. I consider the auto settings to be dangerous and avoid using them. This includes the Raymarine stuff as well as Furuno radars. Mike _____________________________________ Capt. Mike Maurice Beaverton Oregon(Near Portland)
MR
Mark Richter
Fri, Jun 20, 2008 7:49 PM

A number of years ago, I read a test report in Sailboat Reports??  They
tested a number of radar reflector devices, among them a radar reflective US
flag, with metallic threads in it.  This device was one of the lowest
performing reflectors they tested.  I don't know whether this flag is the
same one you are considering or not.

Personally, I'd stick to one of the aluminum corner-cube style reflectors,
the largest size you can reasonably mount.

MArk Richter, m/v Winnie the Pooh
tied up Baldwinsville, NY

A number of years ago, I read a test report in Sailboat Reports?? They tested a number of radar reflector devices, among them a radar reflective US flag, with metallic threads in it. This device was one of the lowest performing reflectors they tested. I don't know whether this flag is the same one you are considering or not. Personally, I'd stick to one of the aluminum corner-cube style reflectors, the largest size you can reasonably mount. MArk Richter, m/v Winnie the Pooh tied up Baldwinsville, NY
K
Keith
Sat, Jun 21, 2008 1:08 PM

Here's a great site for those of you interested in radar reflectors,
performance, etc. Appropriately titled:
http://www.theradarreflectorsite.org/ it covers both passive and active
models.

Also, here are some interesting ones used for military applications... maybe
good choices for boats? Picking the right one seems to be the task.
http://www.rozendalassociates.com/reflectors/monostatic.htm

Keith


We have enough youth.
How about a fountain of "smart"?
----- Original Message -----
From: "Mark Richter" trawlermark@gmail.com

A number of years ago, I read a test report in Sailboat Reports??  They
tested a number of radar reflector devices, among them a radar reflective
US
flag, with metallic threads in it.  This device was one of the lowest
performing reflectors they tested.  I don't know whether this flag is the
same one you are considering or not.

Here's a great site for those of you interested in radar reflectors, performance, etc. Appropriately titled: http://www.theradarreflectorsite.org/ it covers both passive and active models. Also, here are some interesting ones used for military applications... maybe good choices for boats? Picking the right one seems to be the task. http://www.rozendalassociates.com/reflectors/monostatic.htm Keith _____ We have enough youth. How about a fountain of "smart"? ----- Original Message ----- From: "Mark Richter" <trawlermark@gmail.com> >A number of years ago, I read a test report in Sailboat Reports?? They > tested a number of radar reflector devices, among them a radar reflective > US > flag, with metallic threads in it. This device was one of the lowest > performing reflectors they tested. I don't know whether this flag is the > same one you are considering or not.