[117902] in Cypherpunks
RE:
daemon@ATHENA.MIT.EDU (Steve Schear)
Tue Sep 14 15:37:13 1999
Message-Id: <4.1.19990914115304.03cb0b20@popserver.com21.com>
Date: Tue, 14 Sep 1999 12:09:04 -0700
To: "Trei, Peter" <ptrei@rsasecurity.com>, cypherpunks@cyberpass.net
From: Steve Schear <schear@lvcm.com>
In-Reply-To: <D104150098E6D111B7830000F8D90AE8E62A60@exna02.securitydyna
mics.com>
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Reply-To: Steve Schear <schear@lvcm.com>
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At 02:20 PM 9/14/99 -0400, Trei, Peter wrote:
>
>
> Steve Schear[SMTP:schear@lvcm.com] wrote:
> >At 10:46 AM 9/14/99 +0200, you wrote:
> >>At 06:50 PM 9/13/99 -0700, Steve Schear wrote:
> >>>Just the sort of device to position on your front lawn in a large
>wooden
> >>>planter for chamoflage. Set it to a 24-hour timer and use a radio
>shack
> >>>sound level meter and a infrared spot light/photocell as the
>trigger. When
> >>>those jerks cruise by a 2:00 am with their windows down and 500 W
>stereo
> >>>blasting you can smile as their cars sudden quiet and coast to a
>stop some
> >>>distance away. After they flatten their batteries from cranking,
>you might
> >>>even hear them cursing and kicking their tires and trying to
>figure out why
> >>>their cellulars also quit so they can't call a tow truck ;-)
> >>
> >>Yup. Or when the neighbor's dog starts barking, you HERF out
>their TV,
> >>and they come and kick your ass.
> >
> >Hence the need for the photo cell in addition to the noise level as
>a
> >trigger. Perhaps the EMP could be directed by a conductive path
>formed to
> >the target, so as not to severely affect other equipment. Might an
> >inexpensive Nitrogen UV laser do the trick?
> >
> >--Steve
>
> I think this is a non-starter.
>
> Any laser powerful enough to ionize the air and form a conductive
>path
> * is not inexpensive.
Not true. Although Nitrogen lasers are of low efficiency (~ 0.1%) and cannot be
operated CW they are capable of inexpensively (less than than $500) producing
high peak power and repetition rates of more than 20 Hz (100 Hz have been
achieved) with moderate gas mixture flow rates. See
http://plop.phys.cwru.edu/repairfaq/sam/lasercn2.htm
> * takes *lots* of power.
If you want high aggregate power this may be true
> * is not stealthy - a line of ionized air at atmospheric
>pressure
> resembles a lightning bolt.
Have you actually seen such a path. I have, in the lab. If the ionizing source
is a UV laser you'd never know it was there. The lightening bolt ionizes the
air through a breakdown of its insulating properties and great-rapid heating
which causes the thrunder. The UV causes no appreciable heating and though
there is a slight flouresence of the air (the target may brilliantly illuminate
depending upon its properties) its likely to be missed. The laser's brilliance
could damage vision if the target's occupants were looking in its direction.
> * has much more direct ways of disabling a target than just
>acting
> as an EMP conduit.
Unless the peak power and total power delivered (i.e., ergs) are significant no
surface damage to the target may result.
> * probably prevents the HERF stuff from working - you basically
>are
> connecting a wire from from your spark gap to the car body,
>and
> pumping power through it. Metal body cars can shrug off full
> lightning strikes and keep going. The HERF stuff works by
>inducing
> voltages on wires *inside* the car, and so needs a delivery
>mode
> which gets it around corners and bouncing around inside the
>car body.
Perhaps, be an interesting experiment to conduct.
--Steve
N7ZEZ
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At 02:20 PM 9/14/99 -0400, Trei, Peter wrote:<br>
><br>
><br>
><x-tab> </x-tab>Steve
Schear[SMTP:schear@lvcm.com] wrote:<br>
><x-tab> </x-tab>>At 10:46
AM 9/14/99 +0200, you wrote:<br>
><x-tab> </x-tab>>>At
06:50 PM 9/13/99 -0700, Steve Schear wrote:<br>
><x-tab> </x-tab>>>>Just
the sort of device to position on your front lawn in a large<br>
>wooden<br>
><x-tab> </x-tab>>>>planter
for chamoflage. Set it to a 24-hour timer and use a radio<br>
>shack<br>
><x-tab> </x-tab>>>>sound
level meter and a infrared spot light/photocell as the<br>
>trigger. When<br>
><x-tab> </x-tab>>>>those
jerks cruise by a 2:00 am with their windows down and 500 W<br>
>stereo<br>
><x-tab> </x-tab>>>>blasting
you can smile as their cars sudden quiet and coast to a<br>
>stop some<br>
><x-tab> </x-tab>>>>distance
away. After they flatten their batteries from cranking,<br>
>you might<br>
><x-tab> </x-tab>>>>even
hear them cursing and kicking their tires and trying to<br>
>figure out why<br>
><x-tab> </x-tab>>>>their
cellulars also quit so they can't call a tow truck ;-)<br>
><x-tab> </x-tab>>><br>
><x-tab> </x-tab>>>Yup.
Or when the neighbor's dog starts barking, you HERF out<br>
>their TV,<br>
><x-tab> </x-tab>>>and
they come and kick your ass.<br>
><x-tab> </x-tab>><br>
><x-tab> </x-tab>>Hence
the need for the photo cell in addition to the noise level as<br>
>a<br>
><x-tab> </x-tab>>trigger.
Perhaps the EMP could be directed by a conductive path<br>
>formed to<br>
><x-tab> </x-tab>>the
target, so as not to severely affect other equipment. Might an<br>
><x-tab> </x-tab>>inexpensive
Nitrogen UV laser do the trick?<br>
><x-tab> </x-tab>><br>
><x-tab> </x-tab>>--Steve<br>
><br>
><x-tab> </x-tab>I think this
is a non-starter.<br>
><br>
><x-tab> </x-tab>Any laser
powerful enough to ionize the air and form a conductive<br>
>path<br>
><x-tab> </x-tab>
* is not inexpensive.<br>
<br>
Not true. Although Nitrogen lasers are of low efficiency (~ 0.1%) and
cannot be operated CW they are capable of inexpensively (less than than
$500) producing high peak power and repetition rates of more than 20 Hz
(100 Hz have been achieved) with moderate gas mixture flow rates. See
<a href="http://plop.phys.cwru.edu/repairfaq/sam/lasercn2.htm" eudora="autourl"><font color="#0000FF"><u>http://plop.phys.cwru.edu/repairfaq/sam/lasercn2.htm<br>
<br>
</a></font></u>><x-tab> </x-tab>
* takes *lots* of power.<br>
<br>
If you want high aggregate power this may be true<br>
<br>
><x-tab> </x-tab>
* is not stealthy - a line of ionized air at atmospheric<br>
>pressure<br>
><x-tab> </x-tab>
resembles a lightning bolt.<br>
<br>
Have you actually seen such a path. I have, in the lab. If the ionizing
source is a UV laser you'd never know it was there. The lightening bolt
ionizes the air through a breakdown of its insulating properties and
great-rapid heating which causes the thrunder. The UV causes no
appreciable heating and though there is a slight flouresence of the air
(the target may brilliantly illuminate depending upon its properties) its
likely to be missed. The laser's brilliance could damage vision if the
target's occupants were looking in its direction.<br>
<br>
><x-tab> </x-tab>
* has much more direct ways of disabling a target than just<br>
>acting<br>
><x-tab> </x-tab>
as an EMP conduit.<br>
<br>
Unless the peak power and total power delivered (i.e., ergs) are
significant no surface damage to the target may result.<br>
<br>
><x-tab> </x-tab>
* probably prevents the HERF stuff from working - you basically<br>
>are<br>
><x-tab> </x-tab>
connecting a wire from from your spark gap to the car body,<br>
>and <br>
><x-tab> </x-tab>
pumping power through it. Metal body cars can shrug off full <br>
><x-tab> </x-tab>
lightning strikes and keep going. The HERF stuff works by<br>
>inducing <br>
><x-tab> </x-tab>
voltages on wires *inside* the car, and so needs a delivery<br>
>mode <br>
><x-tab> </x-tab>
which gets it around corners and bouncing around inside the<br>
>car body.<br>
<br>
Perhaps, be an interesting experiment to conduct.<br>
<br>
--Steve<br>
N7ZEZ</html>
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