My limited experience with seeing passive returns was a big surprise. A
50' wooden boat broadside in calm waters 300 yards off didn't give
any return until the gain was turned up to the point it would give too
much cutter in rougher water. I also don't see too much of the folks
with the Davis type reflector, three sheets of metal put together at
right angles. The type I have is the Ferdel Bilpper, I was seen by
everyone I asked. I was able to see everyone who had a the any of the
more expensive reflectors that were covered in plastic. Apparently they
have more facets that are in more directions and give a better
reflections. I buddy boated 200 miles up the coast once with some
friends in a 46' Kelly Peterson and a 38foot sloop. The Peterson had
a Davis type reflector and the other sloop had a more modern reflector.
The sloop and I rarely saw the Kelly Peterson and were able to see each
other consistently. I was always amazed at how many boats I didn't
see on the radar. It's a Raymarine SL72
Unfortunately the active radar reflector is not cheap, about 50
percent the coast of the low end Raymarine and about $100 less then a
JRC Radar 1000 MKII. If I had a limited budget and had to choose, I
would take the radar.

John
S/V Pangea

wrote in message
oups.com...

My limited experience with seeing passive returns was a big surprise. A
50' wooden boat broadside in calm waters 300 yards off didn't give
any return until the gain was turned up to the point it would give too
much cutter in rougher water.

snip

John
S/V Pangea

There's a "possible" tuning flaw here.....
Set your picture up for maximum clarity and target acquisition first, then
use "sea clutter" controls (and often, "rain clutter") to reduce clutter in
rougher water, rather than gain/intensity.
Admittedly, you may have to reduce gain at lower ranges, but always try
clutter controls first.
When doing the initial set-up, use a higher range to begin with (3,6,12mi.
depending on your set) and get your best picture there.

otn

"otnmbrd" wrote in message
nk.net...

wrote in message
oups.com...

My limited experience with seeing passive returns was a big surprise. A
50' wooden boat broadside in calm waters 300 yards off didn't give
any return until the gain was turned up to the point it would give too
much cutter in rougher water.

snip

John
S/V Pangea

There's a "possible" tuning flaw here.....
Set your picture up for maximum clarity and target acquisition first, then
use "sea clutter" controls (and often, "rain clutter") to reduce clutter
in rougher water, rather than gain/intensity.
Admittedly, you may have to reduce gain at lower ranges, but always try
clutter controls first.
When doing the initial set-up, use a higher range to begin with (3,6,12mi.
depending on your set) and get your best picture there.

otn

That procedure works well with my JRC Radar 2000. Keep the gain turned up
all the way and increase the sea clutter setting as you go to shorter
ranges. I just started using it this summer and I'm impressed with its
ability to pick up targets. There was, however, an initial tuning
adjustment that I had to go through to get this level of performance. This
procedure peaked the tuning to obtain the maximum number of targets. After
that I just leave it on Auto Tune and adjust sea clutter.

Those active radar reflectors seem overpriced considering all they are doing
is transmitting/receiving just like a radar unit but not providing a display
or any of the other bells/whistles associated with modern radar.

I have a small Furuno on my boat and it picks up everything. On a calm
day I track seagulls and logs. Its only when the sea surface is really
disturbed (25+knots and lots of fetch that the radar starts missing
small boats.

Having driven large ships, I would say that if they are watching their
radar, they will see you even in a small fiberglass boat unless the sea
state or weather is such that clutter is a problem

Gary...does your Furuno unit have alarms
or notifications of "bogies"... ?

~^ beancounter ~^ wrote:
Gary...does your Furuno unit have alarms
or notifications of "bogies"... ?

It probably does but I have never used them. It is a baby ARPA system.

Gary

"Gary" wrote in message
news:l5zaf.392963$oW2.159703@pd7tw1no...
I have a small Furuno on my boat and it picks up everything. On a calm day
I track seagulls and logs. Its only when the sea surface is really
disturbed (25+knots and lots of fetch that the radar starts missing small
boats.

Having driven large ships, I would say that if they are watching their
radar, they will see you even in a small fiberglass boat unless the sea
state or weather is such that clutter is a problem

I'm guessing you're X-Navy (not that it really matters).
Picking up a "small fiberglass" boat on radar in open sea conditions depends
a good deal on luck, the operator, and the radar set,
in question.
I've totally missed large ships, small boats, land masses, weather fronts,
etc., on radar.......
I've picked up seagulls, small boats in 30k wind conditions, land masses
(low lying) at maximum ranges, etc.......
A good deal depends on the particular radar, the particular operator, and
the particular conditions ......
Radar is not a "cure-all"..... for those of you who have installed it and
think you are an expert at using it, as soon as you turn it on or after a
"season" using it ....... forget it ..... you're a trainee.
One in a thousand of you might become good .....some of you will become
passable "mechanics"........ the majority of you will be divided into two
groups:
1. Those with enough common sense to realize they need to be and are aware
of their limited abilities and experience with radar.
2. Those with ego's bigger than their brains.

EG

otn

otnmbrd wrote:
"Gary" wrote in message
news:l5zaf.392963$oW2.159703@pd7tw1no...

I have a small Furuno on my boat and it picks up everything. On a calm day
I track seagulls and logs. Its only when the sea surface is really
disturbed (25+knots and lots of fetch that the radar starts missing small
boats.

Having driven large ships, I would say that if they are watching their
radar, they will see you even in a small fiberglass boat unless the sea
state or weather is such that clutter is a problem


I'm guessing you're X-Navy (not that it really matters).
Picking up a "small fiberglass" boat on radar in open sea conditions depends
a good deal on luck, the operator, and the radar set,
in question.
I've totally missed large ships, small boats, land masses, weather fronts,
etc., on radar.......
I've picked up seagulls, small boats in 30k wind conditions, land masses
(low lying) at maximum ranges, etc.......
A good deal depends on the particular radar, the particular operator, and
the particular conditions ......
Radar is not a "cure-all"..... for those of you who have installed it and
think you are an expert at using it, as soon as you turn it on or after a
"season" using it ....... forget it ..... you're a trainee.
One in a thousand of you might become good .....some of you will become
passable "mechanics"........ the majority of you will be divided into two
groups:
1. Those with enough common sense to realize they need to be and are aware
of their limited abilities and experience with radar.
2. Those with ego's bigger than their brains.

EG

otn


Not X-Navy, still in and Captain of a ship. You are right with you two
categories of people.

I think the original question had to do with radar returns and radar
reflectors. The best way to find out is call another ship or Vessel
Traffic and ask them if the can see you on their radar.

Easy!

Gary wrote in news:b_Waf.407318$1i.381368@pd7tw2no:

Not X-Navy, still in and Captain of a ship. You are right with you two
categories of people.

I think the original question had to do with radar returns and radar
reflectors. The best way to find out is call another ship or Vessel
Traffic and ask them if the can see you on their radar.

Easy!



Captain, is the Canadian Navy installing AIS transponders aboard their
vessels?

--
Larry
(Just an old Electronic Technician keeping the radar running.)