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[email protected] January 4th 05 02:33 AM

Radar burst SOS device
 
I have never used radar so this idea may be useless (ok, so almost all
of em are) but.....
Producing an intense burst of RF is fairly easy by firing a magnet
through a properly shaped coil. This is done in new EMP weapons where
the power output is high enough to fry nearby electronics. So, why not
use the same idea in a 12 guage shell dsigned to fit in one of those
flare launchers. The charge fires the magnet through the coil (this is
destructive as the coil disintegrates) producing a short intense pulse
of RF that will appear on the radar scope. Maybe it could also fire a
cloud of chaff into the air to make a longer lasting return. The idea
is that the initial pulse will get the operators attention and then the
chaff would allow him to see the source.


Roger Long January 4th 05 12:19 PM

Unless the pulse is tied in timing to the one that is sent out by the
receiving sets, there will be no distance information. It wouldn't
help people find you at all.

Radio and GPS have obsoleted this kind of thing. "Hi, I'm here within
this 30 foot diameter circle. Come save me." Even my cell phone has
GPS in it now.

--

Roger Long



wrote in message
oups.com...
I have never used radar so this idea may be useless (ok, so almost
all
of em are) but.....
Producing an intense burst of RF is fairly easy by firing a magnet
through a properly shaped coil. This is done in new EMP weapons
where
the power output is high enough to fry nearby electronics. So, why
not
use the same idea in a 12 guage shell dsigned to fit in one of those
flare launchers. The charge fires the magnet through the coil (this
is
destructive as the coil disintegrates) producing a short intense
pulse
of RF that will appear on the radar scope. Maybe it could also fire
a
cloud of chaff into the air to make a longer lasting return. The
idea
is that the initial pulse will get the operators attention and then
the
chaff would allow him to see the source.




Steve January 4th 05 02:42 PM


wrote in message
oups.com...
of RF that will appear on the radar scope. Maybe it could also fire a
cloud of chaff into the air to make a longer lasting return. The idea
is that the initial pulse will get the operators attention and then the
chaff would allow him to see the source.


Your proposal makes the assumption that someone is watching the radar screen
at the time of the RF burst. This is normally not the case on pleasure or
commercial vessels. Most watch standers only take a quick scan of the radar
display at infrequent intervals or at best, when they are in close proximity
of another vessel or tricky navigation situations. It is possible to set a
radar to trigger a zone alarm but this frequently 'false triggers' and is
seldom used (in my experience).

I have sailed as crew on recreational, commercial and Navy vessels and only
the latter has a dedicated radar watch (combat information center, CIC).
Generally the watch(person) only 'concentrates' on the radar information in
the extreme information mentioned earlier. Monitoring the radar is only one
of many equally important responsibilities of a watch(person).

I believe that a good selection of flares is the best way to attract
attention (assuming the other vessel has a proper watch 'on deck'.

My opinion and experience. FWIW

Steve
s/v Good Intentions



Bruce in Alaska January 4th 05 07:59 PM

In article ,
"Steve" wrote:

wrote in message
oups.com...
of RF that will appear on the radar scope. Maybe it could also fire a
cloud of chaff into the air to make a longer lasting return. The idea
is that the initial pulse will get the operators attention and then the
chaff would allow him to see the source.


Your proposal makes the assumption that someone is watching the radar screen
at the time of the RF burst.


And the radar antenna in question is pointed directly at the source of
the RF Burst. since most radar have a 2.5 to 5.0 degree Horozontal
beamwidth, divided by 360 equals, from less than 1% of the time, to
slightly more than 1% of the time. Would you bet your LIFE on 1%?
Also getting an RF Burst, of sufficent power, in Xband out of a magnet
and coil as you invision, is Exteremly Problematic, and not likely.

Much better to own an Xband Radar Transponder that will reply whenever
it is interigated by an Xband radar, which will give distance and range
information to the radar screen. These have been around for years, but
they cost a bit much for noncommecial operators. Every SOLAS Required
Vessel has one or more onboard.


This is normally not the case on pleasure or
commercial vessels. Most watch standers only take a quick scan of the radar
display at infrequent intervals or at best, when they are in close proximity
of another vessel or tricky navigation situations. It is possible to set a
radar to trigger a zone alarm but this frequently 'false triggers' and is
seldom used (in my experience).

I have sailed as crew on recreational, commercial and Navy vessels and only
the latter has a dedicated radar watch (combat information center, CIC).
Generally the watch(person) only 'concentrates' on the radar information in
the extreme information mentioned earlier. Monitoring the radar is only one
of many equally important responsibilities of a watch(person).

I believe that a good selection of flares is the best way to attract
attention (assuming the other vessel has a proper watch 'on deck'.

My opinion and experience. FWIW

Steve
s/v Good Intentions



Bruce in alaska
--
add a 2 before @

Roger Long January 4th 05 09:15 PM

I believe that a good selection of flares is the best way to attract
attention (assuming the other vessel has a proper watch 'on deck'.


I was once sinking in the middle of the night in Buzzards Bay. I was
pretty sure I could manage the situation and decided not to fire off
flares at the line of fishing vessels that were headed into New
Bedford. Then I realized that they were very likely to run me down
because the boat was small and I was pretty low in the water. I
decided to fire off a few flares. If they stopped, I'd ask them to
report me (no radio) and carry on.

I fired off my flares when I was right in front of them. They never
saw me.

--

Roger Long





Wayne.B January 5th 05 03:16 AM

On Tue, 04 Jan 2005 21:15:22 GMT, "Roger Long"
wrote:

I fired off my flares when I was right in front of them. They never
saw me.


=======================

The only flares I've ever seen that looked like they would really be
useful in an emergency are those that are SOLAS certified. A SOLAS
parachute flare is an awesome sight and it has a peak altitude of
about 1,000 feet.

On the other hand, I doubt that the New Bedford fishing fleet would
stop for anything on the way home, not even a cold beer or a comely
deck hand.

akcarlos January 5th 05 11:38 AM

where do you get a cell phone with a GPS built into it?


Keith January 5th 05 12:16 PM

.... or ignored you.

--


Keith
__
The secret of a good sermon is to have a good beginning and a good ending;
and have the two as close together as possible. -George Burns
"Roger Long" wrote in message
...
I believe that a good selection of flares is the best way to attract
attention (assuming the other vessel has a proper watch 'on deck'.


I was once sinking in the middle of the night in Buzzards Bay. I was
pretty sure I could manage the situation and decided not to fire off
flares at the line of fishing vessels that were headed into New Bedford.
Then I realized that they were very likely to run me down because the boat
was small and I was pretty low in the water. I decided to fire off a few
flares. If they stopped, I'd ask them to report me (no radio) and carry
on.

I fired off my flares when I was right in front of them. They never saw
me.

--

Roger Long







Keith January 5th 05 12:18 PM

I'll second that. The SOLAS handheld flares are MUCH brighter than those
Orion or automotive types. Once I saw them in action, that's all I'll carry
now. I'll describe it like this... if you look at one, you're going to have
a green spot in your vision just like someone flashed a flashbulb right in
your fact. They are REALLY bright.

--


Keith
__
Why do we say something is out of whack? What's a whack?
"Wayne.B" wrote in message
...
On Tue, 04 Jan 2005 21:15:22 GMT, "Roger Long"
wrote:

I fired off my flares when I was right in front of them. They never
saw me.


=======================

The only flares I've ever seen that looked like they would really be
useful in an emergency are those that are SOLAS certified. A SOLAS
parachute flare is an awesome sight and it has a peak altitude of
about 1,000 feet.

On the other hand, I doubt that the New Bedford fishing fleet would
stop for anything on the way home, not even a cold beer or a comely
deck hand.




Rodney Myrvaagnes January 5th 05 06:00 PM

On 5 Jan 2005 03:38:37 -0800, "akcarlos" wrote:

where do you get a cell phone with a GPS built into it?


They all have it. They don't tell you where you are, but they tell the
cel station where you are if use 911, for example.




Rodney Myrvaagnes J36 Gjo/a

Entering your freshman dorm for the first time, and seeing
an axe head come through the door on your right.


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