First Sailing Topic For 2004 . . for me
 

I'm sure there had to be more but I haven't read backwards in time.

This is weather related for voyage planning. Download the 500 milibar
chart. Look for a heavier than normal line marked "564." Stay at least 300
miles south of it for large, fast ships and 500 miles south for our size
vessels. That's good weather. The buffer zone is for just in case one of
the pressure areas decides todip South. Gives you time to go a bit more
south yourself. We saw a lot of sailboats heading across this time but May
is the best month for crossings so that was no surprise. Mostly they showed
up as a tiny speck on the radar first about 10 miles out then eyesight 6-8
miles. And we're 120 feet up! One guy looked like the return from a
carrier! He came close enough and we talked on radio a bit. He had a mast
mounted refector, a regular reflector hung properly and and a second one up
on the windward side flag halyard plus had stuffed his wooden mast with
crumpled tin foil (a old Pardey trick.) Two had radar detectors that picked
up our 10cm beam. All were having thoroughly enjoying a great month of
crossing weather!

Cheers

Michael

First Sailing Topic For 2004 . . for me
 

Michael wrote: He had a mast
mounted refector, a regular reflector hung properly and and a second one up
on the windward side flag halyard plus had stuffed his wooden mast with
crumpled tin foil (a old Pardey trick.) Two had radar detectors that picked
up our 10cm beam.

If you were looking at him with a 10cm set then his mast full of
crumpled tinfoil did nothing to increase his return. The reflecting
surface has to be wider than the wavelength.

Fresh Breezes- Doug King

First Sailing Topic For 2004 . . for me
 

What, no tin foil beanie?

SV

"Michael" wrote in message
...
I'm sure there had to be more but I haven't read backwards in time.

This is weather related for voyage planning. Download the 500 milibar
chart. Look for a heavier than normal line marked "564." Stay at least
300
miles south of it for large, fast ships and 500 miles south for our size
vessels. That's good weather. The buffer zone is for just in case one of
the pressure areas decides todip South. Gives you time to go a bit more
south yourself. We saw a lot of sailboats heading across this time but
May
is the best month for crossings so that was no surprise. Mostly they
showed
up as a tiny speck on the radar first about 10 miles out then eyesight 6-8
miles. And we're 120 feet up! One guy looked like the return from a
carrier! He came close enough and we talked on radio a bit. He had a
mast
mounted refector, a regular reflector hung properly and and a second one
up
on the windward side flag halyard plus had stuffed his wooden mast with
crumpled tin foil (a old Pardey trick.) Two had radar detectors that
picked
up our 10cm beam. All were having thoroughly enjoying a great month of
crossing weather!

Cheers

Michael

First Sailing Topic For 2004 . . for me
 

Now that would explain why the 3cm set picks up a lot of small boat stuff .
...when it's working that is. Both ours are made by Sperry and I wouldn't
give you a nickel for all of them in the whole fleet. Every ship the 3cm
works once in a while and then not well so we normally slave it to the 10cm
for an extra readout station. Ours has been that way for three months. The
other day we were talking about buying a small Furano and wiring it up on
the bridge with a 12 volt battery figuring we couldn't do any worse. So the
10cm picks up the sailboats close in because of that width rule and in the
case below he had three reflectors up? We also get a lot of ghost returns
some do 50 and 60 knots but don't exist! Worse yet we got a bunch of
returns in formation one day in the Red Sea and instead of ghosts turned out
to be the French Navy. Scary!

"DSK" wrote in message
.. .
Michael wrote: He had a mast
mounted refector, a regular reflector hung properly and and a second one
up
on the windward side flag halyard plus had stuffed his wooden mast with
crumpled tin foil (a old Pardey trick.) Two had radar detectors that
picked
up our 10cm beam.

If you were looking at him with a 10cm set then his mast full of
crumpled tinfoil did nothing to increase his return. The reflecting
surface has to be wider than the wavelength.

Fresh Breezes- Doug King

First Sailing Topic For 2004 . . for me
 

Michael wrote:
Now that would explain why the 3cm set picks up a lot of small boat stuff .
..when it's working that is. Both ours are made by Sperry and I wouldn't
give you a nickel for all of them in the whole fleet.

OK, thanks for the info... not shopping for radar at the moment anyway.
I would have thought Sperry made pretty good stuff though.


.... The
other day we were talking about buying a small Furano and wiring it up on
the bridge with a 12 volt battery figuring we couldn't do any worse.

That's work, but because of the power limits you won't get any extra
range mounting it that high up. Get one of the wireless networking ones,
that way you can carry a repeater screen anywhere. Stand radar watch in
the chow line!

Anyway, if the ship is administered under NAVSEA don't change anything
on it. They get very angry (huff huff very angry indeed huff huff) when
people monkey around with their boats. I got in trouble for fixing a
tank level regulator on a whole class of ships, problem is I had a
machinist on a tender make a non-standard part...


... So the
10cm picks up the sailboats close in because of that width rule and in the
case below he had three reflectors up? We also get a lot of ghost returns
some do 50 and 60 knots but don't exist!

I'm not sure why that is, ghost returns seem to come & go even on the
best set ups. Multiple returns can be a timing problem, can you adjust
the rotation of your 10cm set?


... Worse yet we got a bunch of
returns in formation one day in the Red Sea and instead of ghosts turned out
to be the French Navy. Scary!

C'mon the Frech Navy isn't scary. And they couldn't have been in
formation unless the lead ship spilled their wine...

Fresh Breezes- Doug King

First Sailing Topic For 2004 . . for me
 

DSK wrote:


I'm not sure why that is, ghost returns seem to come & go even on the
best set ups. Multiple returns can be a timing problem, can you adjust
the rotation of your 10cm set?


Please explain this statement.

Cheers

First Sailing Topic For 2004 . . for me
 

DSK wrote:

Michael wrote: He had a mast

mounted refector, a regular reflector hung properly and and a second
one up
on the windward side flag halyard plus had stuffed his wooden mast with
crumpled tin foil (a old Pardey trick.) Two had radar detectors that
picked
up our 10cm beam.


If you were looking at him with a 10cm set then his mast full of
crumpled tinfoil did nothing to increase his return. The reflecting
surface has to be wider than the wavelength.


Do you know how wide 10 cm is or has someone been telling you that 4" is
really big?

Bwhahahhahahaha

Cheers

First Sailing Topic For 2004 . . for me
 

Navigator wrote:
Do you know how wide 10 cm is or has someone been telling you that 4" is
really big?

Bwhahahhahahaha

Do you know how to crumple tinfoil so that the crumples are all larger
than 4"?

Put that in your bwahahahah and smoke it.

DSK

First Sailing Topic For 2004 . . for me
 

DSK wrote:
I'm not sure why that is, ghost returns seem to come & go even on the
best set ups. Multiple returns can be a timing problem, can you adjust
the rotation of your 10cm set?

Navigator wrote:
Please explain this statement.

I don't claim to be an expert on radar (like you do with so many
things). However, a ghost image is most often a secondary (or more)
return from a real object, so you see them 180 degrees from the real
return, and/or at some multiple of the distance. If you adjust the sweep
rate or rotation, that seems to make them better... if not disappear,
they at least get smaller. I'd guess the time of the return will come at
a different angle to antennae and not produce the ghosts.

Fresh Electrons- Doug King

First Sailing Topic For 2004 . . for me
 

DSK wrote:

DSK wrote:

I'm not sure why that is, ghost returns seem to come & go even on the
best set ups. Multiple returns can be a timing problem, can you
adjust the rotation of your 10cm set?

Navigator wrote:
Please explain this statement.


I don't claim to be an expert on radar (like you do with so many
things). However, a ghost image is most often a secondary (or more)
return from a real object, so you see them 180 degrees from the real
return, and/or at some multiple of the distance. If you adjust the sweep
rate or rotation, that seems to make them better... if not disappear,
they at least get smaller. I'd guess the time of the return will come at
a different angle to antennae and not produce the ghosts.


This makes no sense to me. The radar does not have significant rotation
(certainly not 180 degrees) between pulse emission and reception.
Where's Gilligan!

Cheers