CB Radios, Cellphones and Gasoline Vapor Ignition

[Frank Bemelman]

"KLM" <klmok88@yahoo.com> schreef in bericht
news:991l5091fq1adsuv7l9st8fhubs2peaodt@4ax.com...

On Fri, 19 Mar 2004 01:32:03 GMT, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:


On a different discussion point, picture the recent Spanish train
bombings (10 set off.) Had the train installed cellphone signal
blocking equipment most of those bombs would probably not have been
set off.

From the fact that few of them went off in the station, where they
would have been far more effective, one may conclude that they were
triggered by simple timers.


Let's say three bombs went off at the station. If the other seven
were prevented from going off that would still have been a significant
victory against terror.

Of course terrorists will always find other ways to detonate their
bombs and the most effective method is still the suicide bomber, no
technology sophistication there. Be forewarned. They will not remain
the technology primitives they are today. In this escalating war new
solutions will have to be found again and again. But in the meantime
I think I have put forth a reasonable proposal that is cheap and
easily implemented, to greatly reduce the opportunities for cellphone
triggered bombs. More important, perhaps to reduce the enormous
effort and costs to provide surveillance in public places.

I like my idea of a built-in transponder chip that can be interrogated
at check-out counters. A portable interrogator can be used to check
abandoned packages from a safe distance without needing to know the
cellphone call number. The Spanish rescue team found an unexploded
bomb laden bag with a cellphone trigger and were very lucky that it
didn't go off.

Forget it. You can't fight terrorism. You can only take away
the anger/frustration that *feeds* it, which takes time and
a lot of wisdom. A roll of duct-tape isn't going to fix anything.


--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)

 

[CW]

Another ignorent one. This thred seems to be full of them.

>"Jack Painter" uttered a bunch of useless crap.

 

[Guy Macon]

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on Usenet?


CW <clinton.magers@comcast.net> says...

You can try to ratioanlize it as much as you want. The willfull electronic
interference of a radio service is a crime.

You need to stop saying things like "is a crime" when posting to
Usenet, a medium that is worldwide.

Also, the following web pages may help you:

Bottom vs. top posting and quotation style on Usenet
http://www.cs.tut.fi/~jkorpela/usenet/brox.html

Why bottom-posting is better than top-posting
http://www.caliburn.nl/topposting.html

+What do you mean "my reply is upside-down"?
http://www.i-hate-computers.demon.co.uk/

The advantages of usenet's quoting conventions
http://homepage.ntlworld.com/g.mccaughan/g/remarks/uquote.html

Why should I place my response below the quoted text?
http://allmyfaqs.com/cgi-bin/wiki.pl?Top-posting_or_bottom-posting

Quoting Style in Newsgroup Postings
http://www.xs4all.nl/%7ewijnands/nnq/nquote.html



--
Guy Macon, Electronics Engineer & Project Manager for hire.
Remember Doc Brown from the _Back to the Future_ movies? Do you
have an "impossible" engineering project that only someone like
Doc Brown can solve? My resume is at http://www.guymacon.com/

 

[Active8]

On Fri, 19 Mar 2004 05:54:13 GMT, KLM wrote:

On Fri, 19 Mar 2004 01:32:03 GMT, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:


On a different discussion point, picture the recent Spanish train
bombings (10 set off.) Had the train installed cellphone signal
blocking equipment most of those bombs would probably not have been
set off.

From the fact that few of them went off in the station, where they
would have been far more effective, one may conclude that they were
triggered by simple timers.


Let's say three bombs went off at the station. If the other seven
were prevented from going off that would still have been a significant
victory against terror.

Of course terrorists will always find other ways to detonate their
bombs and the most effective method is still the suicide bomber, no
technology sophistication there. Be forewarned. They will not remain
the technology primitives they are today. In this escalating war new
solutions will have to be found again and again. But in the meantime
I think I have put forth a reasonable proposal that is cheap and
easily implemented, to greatly reduce the opportunities for cellphone
triggered bombs. More important, perhaps to reduce the enormous
effort and costs to provide surveillance in public places.

I like my idea of a built-in transponder chip that can be interrogated
at check-out counters. A portable interrogator can be used to check
abandoned packages from a safe distance without needing to know the
cellphone call number. The Spanish rescue team found an unexploded
bomb laden bag with a cellphone trigger and were very lucky that it
didn't go off.

Objections of others partially aside, you're getting close to a
workable idea. If a few of the off the shelf trak phones had to be
recalled or exchanged for new ones, any old ones the T's stockpiled
would be worthless.

The RFID systems could be set up to either cover a small area like a
turnstile or a larger area depending on how you wanted to go about
implementing security for a given loacation.

The problem to overcome is that we don't want to set one off in a
crowd, so we don't want it to ring in response to the RFID
interrogation. We also don't want an invasion of privacy, so a
generic RFID response would be the solution.

We also don't want the thing detonating from the interrogation with
people around and that's the biggest prob. You have to admit only
one person at a time into the area. That's not too bad. It's common
courtesy to stand back from someone using an ATM so maybe a few feet
will do. Like in a bank line.

I don't imagine the T's will want the thing detonating at the check
point either, so they'll probably have that figured out and an
inspection of the phone should reveal anything suspicious.

I think the real problem is the human factor. When baggage handlers
make $15/hr and get full union benefits, while the security
contractor pays his monkeys minimum wage, you have apathy. This is
no BS, it's serious. Back in the 80's after the Berlin disco bombing
and a few other attacks, people were talking a lot about security.
And talking is about all they did.

I went through the security check at the Atlanta airport and after
being admitted into the so-called secure area I had to go to the
bathroom so I asked where it was. Damned if it wasn't outside the
secure area. I went out through an unckecked passage and came right
back in. No one bothered checking me.

Last few times I went through a metal detector, I set it off. The
first time, the guard checked me with the wand and suggested it was
my shoes or the jacket zipper, but didn't ask me to remove them. The
second time (a month later) I went through, the same guard was
there. I just pointed to the shoes and the zipper and I was in.
Friggin' apathy. Maybe he remembered that the wand didn't indicate a
big enough chunk of metal, but that jacket fit just about right to
conceal a Glock.
--
Best Regards,
Mike

 

[Costas Vlachos]

"Spehro Pefhany" <speffSNIP@interlogDOTyou.knowwhat> wrote in message
news:cojk50puqeltf2bjfj83kor0jvetrc0vft@4ax.com...

On Fri, 19 Mar 2004 01:08:01 GMT, the renowned KLM <klmok88@yahoo.com
wrote:

On a different discussion point, picture the recent Spanish train
bombings (10 set off.) Had the train installed cellphone signal
blocking equipment most of those bombs would probably not have been
set off.

From the fact that few of them went off in the station, where they
would have been far more effective, one may conclude that they were
triggered by simple timers.

Best regards,
Spehro Pefhany

Yes, that is correct - at least that's what was said on the news channels
here in the UK. The Spanish bombs were triggered by mobile phones set on
alarm at 7:39am IIRC - the phones didn't even have to have SIM cards in
them. No signal jamming equipment could have prevented them from going off.

cheers,
Costas

 

[John Woodgate]

I read in sci.electronics.design that KLM <klmok88@yahoo.com> wrote (in
<r4tk50dvrj3uhgvcukdhot3c6u7am184rb@4ax.com&gt about 'Cellphones and
Bombs', on Fri, 19 Mar 2004:

To the objections from other posts; of course a determined terrorist
will always get through. Who can stop one who is willing to blow
himself up.

If he acts entirely alone, like the one who blew up the gay pub in
London, no-one, unless by chance - nail-bomb in Brixton.

But anyone who confides in others is vulnerable to infiltration, and
there's a lot of that going on, you can be sure.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Bob Myers]

"KLM" <klmok88@yahoo.com> wrote in message
news:62ik50dct1tfjjsraq43maub22d74fauce@4ax.com...

On Thu, 18 Mar 2004 16:53:28 -0800, "CW" <clinton.magers@comcast.net
wrote:

Do you know what the word ILLEGAL means? It is very obvious that you are
ignorant of the technical details and I am not going to be your
electronics
teacher. It is illegal for a reason.


Terrorists are using cellphones to kill and maim hundreds of people
and you are maintaining that unrestrcted CP use is a god given
inviolable right.

Nope. He's simply pointed out, quite correctly, that willful
interference with a legitimate radio service is very , very illegal,
and it is so for some very good reasons.

Besides, "jamming" cell phones is a stupid and ineffective idea anyway.
You can't reliably "jam" such things within a limited area (which is one
reason for the laws in question - to RELIABLY jam phones within an
area that IS under your legal control, you MUST create signals that will
cause interference OUTSIDE that area. Hence, don't do it.) A far
better plan is to simply shield the area in question from ANY RF
transmissions - easily and relatively cheaply done, and will cause no
legal or other hassles, or unintended interference. And you can still
bring in any RF-based info you DO want - TV, radio, etc. - via a
cable.

Bob M.

 

[Bob Myers]

"Eric R Snow" <etpm@whidbey.com> wrote in message
news:c4kk50po9mgvusv50vvn9jeq32v0ofklhl@4ax.com...

Is it always illegal to block cell phone signals? I ask because the
hospital where I was a patient had an area where cell phones would not
work and as I seem to recall had signage stating that fact and how
cell phone usage in that area was prohibited.

Cell phone use was prohibited because of the supposed
interference with vital electronic equipment in the area - very
unlikely, but the hospital is doing a CYA here. The fact that
the phones wouldn't work anyway is more than likely
completely unrelated, and due to the building itself shielding the
phones from the outside.

Bob M.

 

[Bob Myers]

"KLM" <klmok88@yahoo.com> wrote in message
news:mcfk505dkgl77pi8ev4t4mdkor9fvjtjof@4ax.com...

Why not include a circuit in every cellphone that will cause the
answer bell to ring when anyone carrying a cellphone crosses one of
these interrogators. Maybe have the circuitry activate a different
ring tone or ring pattern from the normal call ring. Its extremely
short range and won't interefere with normal cellphone use.

Simple - again, the strong likelihood of interference with cell phones
AND other legitimate services. Plus the rather obvious fact that it
won't achieve the desired goal; once these things were placed into
service, it would be trivially easy for a "cell phone bomber" to disable
their phone's ringer. Or to cause a dummy ringer (the one that doesn't
have to do with the bomb) to go off and thus defeat the security.

You really should learn a bit more about how these things work before
proposing supposed "solutions" to the supposed "problem."

Bob M.

 

[John Woodgate]

I read in sci.electronics.design that Me <Me@shadow.orgs> wrote (in <Me-
023AAE.09235419032004@netnews.worldnet.att.net&gt about 'CB Radios,
Cellphones and Gasoline Vapor Ignition', on Fri, 19 Mar 2004:

This design
change isn't really that expensive, but the testing that is required to
receive the "Intrinsically Safe" Lable, is extremely expensive.

There are strong suspicions in some countries that it is quite
unjustifiably expensive, because only a few facilities offer it. More
competition is required. Or a government investigation.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Jan Panteltje]

KLM <klmok88@yahoo.com> wrote in message news:<f4ck5090kfkchrdf0rrjj7o4nl9v1v9oqa@4ax.com>...

On Thu, 18 Mar 2004 13:00:55 -0800, "CW" <clinton.magers@comcast.net

And cellphone signal blocking is localized, short range, same as WiFi.
Put up a sign to that effect in your business premise. Those who feel
they must have their cellphone access 24/7 can always step outside
the door or avoid the place. That business will survive because there
are a miniscule number of 24/7 cellphone freaks.

Anyway the use of cellphones while driving is banned in many states in
the US and worldwide. What is so different in banning their use in
selected public places. The only difference is that signal blocking
is applied universally in that defined building area, and without
having intrusive checks being made on anyone to effect compliance.

To prevent the use of cellphones ANYWHERE kills an industry, I want to
be able to use it everywhere, OK handsfree in a car.
If the terrorist intention is to damage industry, economy, then yes.
Else live with the danger.
JP

 

[Richard Henry]

"Reg Edwards" <g4fgq.regp@ZZZbtinternet.com> wrote in message
news:c3dcok$bfn$1@titan.btinternet.com...

I AM old enough to remember the pre-war and the phoney-war impressions of
the population of the cities of Birmingham and Coventry about the
capabilities of the Luftwaffer.

It was "They'll never get this far."

At the same time the citizens of Cologne, Hamburg, Berlin and Dresden were
saying much the same thing.

Whath they found out was that they don't have to ALL get through.

 

[Jeff]

"Bob Myers" <nospamplease@address.invalid> wrote in
news:hUG6c.1277$Gu4.361@news.cpqcorp.net:

"KLM" <klmok88@yahoo.com> wrote in message
news:62ik50dct1tfjjsraq43maub22d74fauce@4ax.com...
On Thu, 18 Mar 2004 16:53:28 -0800, "CW" <clinton.magers@comcast.net
wrote:

Do you know what the word ILLEGAL means? It is very obvious that
you are ignorant of the technical details and I am not going to be
your
electronics
teacher. It is illegal for a reason.


Terrorists are using cellphones to kill and maim hundreds of people
and you are maintaining that unrestrcted CP use is a god given
inviolable right.

Nope. He's simply pointed out, quite correctly, that willful
interference with a legitimate radio service is very , very illegal,
and it is so for some very good reasons.

Besides, "jamming" cell phones is a stupid and ineffective idea
anyway. You can't reliably "jam" such things within a limited area
(which is one reason for the laws in question - to RELIABLY jam phones
within an area that IS under your legal control, you MUST create
signals that will cause interference OUTSIDE that area. Hence, don't
do it.) A far better plan is to simply shield the area in question
from ANY RF transmissions - easily and relatively cheaply done, and
will cause no legal or other hassles, or unintended interference. And
you can still bring in any RF-based info you DO want - TV, radio, etc.
- via a cable.

Bob M.

Spot on, thats whats used where possible in sensitive buildings in the
UK.

The use of CP's for these purposes has been going on for 30 years at
least. It's not new and various means to counter it have been tried with
various success. There's a tendancy to assume these people are stupid as
well as socially corrupt. Not true. The IRA for instance used cp's in the
70's and 80's bombing of London and the mortar attack on 10 Downing
street while the cabinet was in session. The IRA's technique was to use
two cell phones and a sequence of calls to arm and trigger the weapon.
Once the bomb was placed and the phone was on and receiving signal the
bomb was also set to go off if the phone was switched off or the signal
lost - as it would be if the area was 'jammed'.

Jamming the phone service could actually set the thing off where the
planter wanted it to be. Not a good idea.

As an aside, given that Bush has started his war on terrorism, terrorists
and all that support them, does that mean he's going to pursue all those
who have and still do support the IRA and 'the cause' who where almost
entirely funded from the US?

 

[Eric R Snow]

On Fri, 19 Mar 2004 18:24:42 GMT, "Bob Myers"
<nospamplease@address.invalid> wrote:

"Eric R Snow" <etpm@whidbey.com> wrote in message
news:c4kk50po9mgvusv50vvn9jeq32v0ofklhl@4ax.com...
Is it always illegal to block cell phone signals? I ask because the
hospital where I was a patient had an area where cell phones would not
work and as I seem to recall had signage stating that fact and how
cell phone usage in that area was prohibited.

Cell phone use was prohibited because of the supposed
interference with vital electronic equipment in the area - very
unlikely, but the hospital is doing a CYA here. The fact that
the phones wouldn't work anyway is more than likely
completely unrelated, and due to the building itself shielding the
phones from the outside.

Bob M.


I figured that the building was a shield. I didn't know if it was

legal to do it. I guess if a signal is blocked passively it's OK. But
sending out a jamming signal isn't.
ERS

 

[Bob Myers]

"Eric R Snow" <etpm@whidbey.com> wrote in message
news:0anm5097vfjkqml1a9c8qr15gk8be3gr56@4ax.com...

I figured that the building was a shield. I didn't know if it was
legal to do it. I guess if a signal is blocked passively it's OK. But
sending out a jamming signal isn't.

Exactly right. You have no guarantee that a given piece
of RF technology will be able to access an external service
while in any building. And if the owners of that building want
to sheath the entire thing in metal and put screens, etc.,
on the windows, that's just too bad for anyone who'd want
to use a cell phone while inside. And that course doesn't require
anything NEARLY as stupid as trying to actively interfere
with the service.

Bob M.

 

[Jan Panteltje]

Forget it. You can't fight terrorism. You can only take away
the anger/frustration that *feeds* it, which takes time and
a lot of wisdom. A roll of duct-tape isn't going to fix anything.
Those are very wise words.

Thats *IS* exactly how it is.
Unfortunatly the big terrorist Bush wants to have war everywhere,
so he can sell weapons, and will make unrest everywhere.
His men are now in Siria, perhaps also in Taiwan, Bush was talking today
of 'world is at war' well, that for sure is what he is directing every
possible energy towards.
So my hopes of this realization being realized so to speak are not great.
Only chance we have, in our lives, is to enjoy this moment given to us,
NOW, there are no guarantees for the future, and the past is gone.
There are however people in this world trying to make people realize
that peace in an inner experience, your own choice so to speak, and
atainable, for example my Guru www.maharaji.org.
So, as long as there is a way out, we are free
JP

 

[John Michael Williams]

Captain794@yahoo.com (The Captain) wrote in message news:<7199d521.0403181757.7ab27279@posting.google.com>...

Dave Shrader <david.shrader@comcast.net> wrote in message news:<Xu36c.33004$po.292953@attbi_s52>...
John Michael Williams wrote:

SNIP

However, the first radios transmitted
sparks, so in principle it should be possible to
transmit near a long wire separated by a small gap from
ground or another wire and get a small spark. So, I
decided to try an experiment.

SNIP

There is one other potential source for a spark that you did not
investigate.

A make/break contact in a switch causes sparks when opened. The US
Military specifies special shielded switches for their explosive, gas
vapor, etc., environments.

So, it is possible that pressing the PTT or the ON/OFF switch causes the
necessary spark. Remember the Apollo ground fire. A switch/spark caused
an oxygen explosion.

Actually, anyone who has worked in the offshore oil industry will be
familiar with the concept of intrinsic safety. This requires that no
electronic instrument shall be able to ignite a mixture of air and
inflamable vapour or gas. All handheld radios used on rigs are
intrinsically safe, making them far more expensive than the standard
variety.

I very much doubt that cell phones are buit to intrinsicly safe
standards, and under those circumstances I would certainly not feel
safe near someone yacking while filling.

So, an interesting querstion is; does your phone conform to UL
requirements for intrinsic safety? And if not, why are you using it
in an area where an explosive gas air mixture is possible?

Cap

Actually, a former maritime safety engineer Emailed me
about this. However, he could not locate the law or regulation
which defines "intrinsic safety". If you can find a law
or regulation governing operation of a transmitter around
a gas pump, please post it.

I have no idea how UL testing would pertain to a battery operated
device incapable, itself, of electrocuting anyone. However, the
battery eliminator which I have (but did not use in the
experiment I described) is UL approved.

On the safety issue, the same engineer also told me he was able
to create visible sparks with a 100 W transmitter, holding
the antenna near a piece of metal. However, for the following
reason, I suspect the sparks were because his transmitter was
earth-grounded:

The handheld CB I used had a completely insulated rubber antenna
and of course had no ground connection. I replaced the rubber
antenna with a telescoping metal one. I then keyed the transmit
button (as above) in the dark, while trying to get a spark by
bringing the tip near a 1 m x 1 m aluminum 1/4 in plate (ungrounded).
I could see nothing, although touching the metal caused the CB's
power out bar to indicate a drop in power. The plate should have
been an effective AC ground at ~27 MHz.

So, neither induction into a wire nor electrical direct contact
seems likely to make a visible spark, with a 5 W CB transmitter.

I would only expect a 100 mV or so spark anyway, which would be
hard to see.

So, I'm not convinced that a cell phone could cause a spark, either.


I agree that key closure sparks might be possible internal to
the device, and that neither it nor a cell phone would be likely
to have been designed to suppress a flash from such a source.

However, the issue I have tried to address here is a spark from
the RF, not from generic electrical causes. I don't doubt that
gasoline vapor is inflammable in a generic sense.

John
jwill@AstraGate.net
John Michael Williams

 

[Jan Panteltje]

"Costas Vlachos" <c-X-vlachos@hot-X-mail.com> wrote in message news:<c3er8t$69c$1@sparta.btinternet.com>...

Yes, that is correct - at least that's what was said on the news channels
here in the UK. The Spanish bombs were triggered by mobile phones set on
alarm at 7:39am IIRC - the phones didn't even have to have SIM cards in
them. No signal jamming equipment could have prevented them from going off.

cheers,
Costas
I ma not sure abou that other phone, in a backpack, it rang, and that

is
how they found it.
So it MUST have had a sim card.
When I heard that news, I knew they would get the guys in hours.
One look at that sim, and a look at the telco's logs, and you have the
whole network
It proves these guys are really dumies in that stuff.
Nevertheless very very dangerous.
JP

 

[Cecil Moore]

Jan Panteltje wrote:

Forget it. You can't fight terrorism. You can only take away
the anger/frustration that *feeds* it, which takes time and
a lot of wisdom. A roll of duct-tape isn't going to fix anything.

Those are very wise words.
Thats *IS* exactly how it is.

Actually, we fought nazi terrorism during WWII and won. Seems
to me it would be more appropriate to say: "The fight against
terrorism is a never ending war unless we take away the
anger/frustration that *feeds* it."
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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[KLM]

On Fri, 19 Mar 2004 10:29:15 +0100, "Frank Bemelman"
<f.bemelmanx@planet.invalid.nl> wrote:

Forget it. You can't fight terrorism. You can only take away
the anger/frustration that *feeds* it, which takes time and
a lot of wisdom. A roll of duct-tape isn't going to fix anything.

I agree with you 100%. But its an emotional subject I avoid
assiduously as any argument that says the Arabs and the Muslims have
good reason to feel the way they do will invite very angry flames from
a sector of shoot-em-all-first Americans. For crying out loud, even
Americans who hold this view (Arabs and Muslims have valid grievences)
have been intimidated into silence by their own side. Until the
American right wing come around to dealing with the root causes of
why people are willing to blow themselves up to take out their
enemies, suicide bombings will continue.

The issue is intimately linked with what's going on in Israel. Again
I refuse to get caught in the middle as one will be mauled by both
parties whatever one says. Was it Mercuto who said "Pox on both
Houses" in Romeo and Juliet? Exactly my feelings.

-------------------------------------
I originally used the term CP signal blocking and there were
off-the-shelf equipment openly available for sale some years ago. It
blocks signals to your establishment, eg. inside a restaurant, in
specific frequencies only I believe. I presume the signal blocker
does not block signals outside the premise for that would be clearly
illegal. It does not jam signals with dirty noise that intereferes
with the safe operation of other electronic equipment which is also
clearly illegal.

In any case the suggestion for cellphone signal free areas is just a
suggestion. Of course it wouldn't stop CP triggered bombings for they
will just plant them elsewhere. But at least there is a chance that
the more high value target - a very crowded place in a high profile
establishment - may be spared.