GPS Question

[Country Loon]

There are GPS systems in cars available where you can check its location if
stolen.
I have a GPS unit and find it difficult to get a fix in my house.I have to
hold it outside for a while and quite high to get any form of signal lock.
So how therefore can a hidden GPS receiver get any signal? After all, hiding
it under the dash will just screen the signal.

Tom

 

[Dave VanHorn]

My gps unit had it's antenna mag-mounted to the top of the in-dash radio.
worked fine.


--
KC6ETE Dave's Engineering Page, www.dvanhorn.org
Microcontroller Consultant, specializing in Atmel AVR

 

[Paul Burridge]

On Sat, 23 Oct 2004 20:07:45 -0500, "Dave VanHorn"
<dvanhorn@cedar.net> wrote:

My gps unit had it's antenna mag-mounted to the top of the in-dash radio.
worked fine.

Theft prevention is, of course, a jolly good thing. However, like all
these advances in technology, there's a potential for misuse. Any
malifactor can attach one of these devices to a car and use it to
track a person's movements. Terrorists, potential kidnappers, private
detectives, Big Brother, could be anyone for any reason. That's why
GPS jammers are becoming increasingly readily available. There are
several sites on the internet where schematics for them can also be
downloaded. Long live freedom!

--

"What is now proved was once only imagin'd." - William Blake, 1793.

 

[Dave VanHorn]

Theft prevention is, of course, a jolly good thing. However, like all
these advances in technology, there's a potential for misuse. Any
malifactor can attach one of these devices to a car and use it to
track a person's movements.

After you add a processor, modem, and radio, and power for all that.
See my web page, specifically the "dude, where's my car" link.

--
KC6ETE Dave's Engineering Page, www.dvanhorn.org
Microcontroller Consultant, specializing in Atmel AVR

 

[Paul Burridge]

On Sun, 24 Oct 2004 09:01:50 -0500, "Dave VanHorn"
<dvanhorn@cedar.net> wrote:

Theft prevention is, of course, a jolly good thing. However, like all
these advances in technology, there's a potential for misuse. Any
malifactor can attach one of these devices to a car and use it to
track a person's movements.

After you add a processor, modem, and radio, and power for all that.
See my web page, specifically the "dude, where's my car" link.

THere are devices out there on the market that can be attached to a
target vehicle, left for a month or whatever and then recovered which
will record the movement of that vehicle over the entire period,
storing the info within the device itself. The potential for abuse is
self-evident.

--

"What is now proved was once only imagin'd." - William Blake, 1793.

 

[Jim Douglas]

For those with teenage drivers, place the GPS somewhere where it can reach
they skys, the check max speed, miles, etc.

"Country Loon" <fitlikemin@mearns.fairmers.co.uk> wrote in message
news:1098575449.411801@ftpsrv1...

There are GPS systems in cars available where you can check its location
if
stolen.
I have a GPS unit and find it difficult to get a fix in my house.I have to
hold it outside for a while and quite high to get any form of signal lock.
So how therefore can a hidden GPS receiver get any signal? After all,
hiding
it under the dash will just screen the signal.

Tom

 

[Dave VanHorn]

THere are devices out there on the market that can be attached to a
target vehicle, left for a month or whatever and then recovered which
will record the movement of that vehicle over the entire period,
storing the info within the device itself. The potential for abuse is
self-evident.

True, but one should notice things attached to one's vehicle.

--
KC6ETE Dave's Engineering Page, www.dvanhorn.org
Microcontroller Consultant, specializing in Atmel AVR

 

[Jim Thompson]

On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Paul Burridge <pb@notthisbit.osiris1.co.uk> wrote in message news:<ahcnn0ljrtc3nd0gh0o6vae902og97u7rh@4ax.com>...
On Sat, 23 Oct 2004 20:07:45 -0500, "Dave VanHorn"
dvanhorn@cedar.net> wrote:

My gps unit had it's antenna mag-mounted to the top of the in-dash radio.
worked fine.

Theft prevention is, of course, a jolly good thing. However, like all
these advances in technology, there's a potential for misuse. Any
malifactor can attach one of these devices to a car and use it to
track a person's movements. Terrorists, potential kidnappers, private
detectives, Big Brother, could be anyone for any reason. That's why
GPS jammers are becoming increasingly readily available. There are
several sites on the internet where schematics for them can also be
downloaded. Long live freedom!

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Tom, Paul Burridge is the resident village idiot. Give us all some
relief and ignore his posts. Thanks!

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Ian Stirling]

Jim Douglas <james.douglas@genesis-software.com> wrote:

For those with teenage drivers, place the GPS somewhere where it can reach
they skys, the check max speed, miles, etc.

<snip quoted message incorrectly placed at bottom>

Max speed can be way off.
If it loses lock, then some models won't blank out the max speed.
So, when lock comes back, it assumes you were going the same way you
were when you lost lock and then computes the speed from this imaginary
point back to the position it's just obtained.
Miles will usually be more accurate.

 

[Country Loon]

"Tom Seim" <soar2morrow@yahoo.com> wrote in message
news:6c71b322.0410241253.5cf6031d@posting.google.com...

Paul Burridge <pb@notthisbit.osiris1.co.uk> wrote in message
news:<ahcnn0ljrtc3nd0gh0o6vae902og97u7rh@4ax.com>...
On Sat, 23 Oct 2004 20:07:45 -0500, "Dave VanHorn"
dvanhorn@cedar.net> wrote:

My gps unit had it's antenna mag-mounted to the top of the in-dash
radio.
worked fine.

Theft prevention is, of course, a jolly good thing. However, like all
these advances in technology, there's a potential for misuse. Any
malifactor can attach one of these devices to a car and use it to
track a person's movements. Terrorists, potential kidnappers, private
detectives, Big Brother, could be anyone for any reason. That's why
GPS jammers are becoming increasingly readily available. There are
several sites on the internet where schematics for them can also be
downloaded. Long live freedom!

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Not to mention cruise missiles.You don't want to stop them doing there
business for the oil trade now do you.

Tom

 

[Paul Burridge]

On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Yessiree! I've just seen a bunch of them for sale in Exchange & Mart
(a UK publication) for 299 quid a piece. They're stated as 10mW output
@ approx. 1.5Ghz and not licensable in the UK. This is the type of
device which would be *ideal* to 'install-and-forget' in your own car
to thwart the snoopers. 10mW is just about enough to create a cloud of
RF 'noise' around your car and prevent any GPS-based device attached
to it from being able to sense and report your position. At the same
time, the power level is sufficiently low enough not to cause any
undue interference beyond a few tens of yards from the vehicle
(depending on antenna efficiency, mounting position and so forth).
--

"What is now proved was once only imagin'd." - William Blake, 1793.

 

[Ian Stirling]

Paul Burridge <pb@notthisbit.osiris1.co.uk> wrote:

On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Yessiree! I've just seen a bunch of them for sale in Exchange & Mart
(a UK publication) for 299 quid a piece. They're stated as 10mW output
@ approx. 1.5Ghz and not licensable in the UK. This is the type of
device which would be *ideal* to 'install-and-forget' in your own car
to thwart the snoopers. 10mW is just about enough to create a cloud of
RF 'noise' around your car and prevent any GPS-based device attached
to it from being able to sense and report your position. At the same
time, the power level is sufficiently low enough not to cause any
undue interference beyond a few tens of yards from the vehicle
(depending on antenna efficiency, mounting position and so forth).

Anyone using one of these should be prosecuted to the fullest possible
extent of the law.

GPS transmitters are about 50W for a whole hemisphere.
The civilian transmission ones have a coding gain of 1024, so that's
an equivalent power of 50Kw.
Now, the area of a circle with radius 6000Km is about 3*10^13m^2.
Or an equivalent power density of 8nW/m^2 (unless I've blown off
some units).
Now, 10mW/8nW = 1.2 million square meters, or a hemisphere about a
kilometer in radius.

 

[hamilton]

Fred Bloggs wrote:

Right- right, clueless, moron. So now every terrorist in the world knows
had to bring the unprotected US ATC to its knees- thnx to Bush. You are
nothing but a grade A idiot.

Fred, Fred, chill out man, have a homebrew.

Every terrorist are not the idiots you believe them to be.
They are engineers as well. They can do the math themselves.
Our discussion here will do very little in helping the next terrorist
attack.

Good Russian technology will help them more then we ever will.

 

[Paul Burridge]

On 25 Oct 2004 13:45:20 GMT, Ian Stirling <root@mauve.demon.co.uk>
wrote:

Anyone using one of these should be prosecuted to the fullest possible
extent of the law.

As should those who covertly attach spying equipment to a respectable,
private individual's car...

GPS transmitters are about 50W for a whole hemisphere.
The civilian transmission ones have a coding gain of 1024, so that's
an equivalent power of 50Kw.

What the hell is "coding gain"?

Now, the area of a circle with radius 6000Km is about 3*10^13m^2.
Or an equivalent power density of 8nW/m^2 (unless I've blown off
some units).
Now, 10mW/8nW = 1.2 million square meters, or a hemisphere about a
kilometer in radius.

Nonsense. Your power density calculation may or may not be correct,
but unless you know the efficiency of the installation to the vehicle,
you can't rely on that calculated figure. It's likely to be *much*
lower. This is 1.5Ghz, remember, so placement is critical to the
radiated field. You're hardly likely to want or need the thing mounted
on the vehicle's roof, afterall.

--

"What is now proved was once only imagin'd." - William Blake, 1793.

 

[Clarence]

"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:417d036e$0$80659$ed2619ec@ptn-nntp-reader03.plus.net...

Paul Burridge <pb@notthisbit.osiris1.co.uk> wrote:
On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Yessiree! I've just seen a bunch of them for sale in Exchange & Mart
(a UK publication) for 299 quid a piece. They're stated as 10mW output
@ approx. 1.5Ghz and not licensable in the UK. This is the type of
device which would be *ideal* to 'install-and-forget' in your own car
to thwart the snoopers. 10mW is just about enough to create a cloud of
RF 'noise' around your car and prevent any GPS-based device attached
to it from being able to sense and report your position. At the same
time, the power level is sufficiently low enough not to cause any
undue interference beyond a few tens of yards from the vehicle
(depending on antenna efficiency, mounting position and so forth).

Anyone using one of these should be prosecuted to the fullest possible
extent of the law.

GPS transmitters are about 50W for a whole hemisphere.
The civilian transmission ones have a coding gain of 1024, so that's
an equivalent power of 50Kw.
Now, the area of a circle with radius 6000Km is about 3*10^13m^2.
Or an equivalent power density of 8nW/m^2 (unless I've blown off
some units).
Now, 10mW/8nW = 1.2 million square meters, or a hemisphere about a
kilometer in radius.

So it is even more effective tha expected?

 

[Rich Grise]

On Mon, 25 Oct 2004 14:24:24 +0100, Paul Burridge wrote:

On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Yessiree! I've just seen a bunch of them for sale in Exchange & Mart
(a UK publication) for 299 quid a piece. They're stated as 10mW output
@ approx. 1.5Ghz and not licensable in the UK. This is the type of
device which would be *ideal* to 'install-and-forget' in your own car
to thwart the snoopers. 10mW is just about enough to create a cloud of
RF 'noise' around your car and prevent any GPS-based device attached
to it from being able to sense and report your position. At the same
time, the power level is sufficiently low enough not to cause any
undue interference beyond a few tens of yards from the vehicle
(depending on antenna efficiency, mounting position and so forth).

Of course, that's going to mess up your own GPS. So, every time
you stop, turn off your jammer, and turn on your GPS to get your
bearings, they re-lock on your new position.

:-
Rich

 

[Rich Grise]

On Mon, 25 Oct 2004 17:13:00 +0100, Paul Burridge wrote:

On 25 Oct 2004 13:45:20 GMT, Ian Stirling <root@mauve.demon.co.uk
wrote:

Anyone using one of these should be prosecuted to the fullest possible
extent of the law.

As should those who covertly attach spying equipment to a respectable,
private individual's car...

Or any individual's car, in a country where the constitution is still
in force.

Thanks,
Rich

 

[Rich Grise]

On Mon, 25 Oct 2004 16:17:55 +0000, Clarence wrote:

"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:417d036e$0$80659$ed2619ec@ptn-nntp-reader03.plus.net...
Paul Burridge <pb@notthisbit.osiris1.co.uk> wrote:
On 24 Oct 2004 13:53:35 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Be aware that in the U.S., and many other countries, you will be
violating federal law by using these jammers. Worse, you could
interfere with aircraft navigational equipment. Thousands of U.S.
airports have GPS instrument approaches. The consequences of jamming
this equipment are horrific.

Yessiree! I've just seen a bunch of them for sale in Exchange & Mart
(a UK publication) for 299 quid a piece. They're stated as 10mW output
@ approx. 1.5Ghz and not licensable in the UK. This is the type of
device which would be *ideal* to 'install-and-forget' in your own car
to thwart the snoopers. 10mW is just about enough to create a cloud of
RF 'noise' around your car and prevent any GPS-based device attached
to it from being able to sense and report your position. At the same
time, the power level is sufficiently low enough not to cause any
undue interference beyond a few tens of yards from the vehicle
(depending on antenna efficiency, mounting position and so forth).

Anyone using one of these should be prosecuted to the fullest possible
extent of the law.

GPS transmitters are about 50W for a whole hemisphere.
The civilian transmission ones have a coding gain of 1024, so that's
an equivalent power of 50Kw.
Now, the area of a circle with radius 6000Km is about 3*10^13m^2.
Or an equivalent power density of 8nW/m^2 (unless I've blown off
some units).
Now, 10mW/8nW = 1.2 million square meters, or a hemisphere about a
kilometer in radius.

So it is even more effective tha expected?

Yeah, Clarence. Set a GPS jammer on top of your car so the fanatical
libaral nazi democrats can't track you down and use their mind rays
to zombize you into voting for Kerry. And stay close to your local
FBI office with your jammer, so they can protect you from the liberal
menace.

Good Luck!
Rich

 

In <pan.2004.10.25.20.11.37.798083@example.net>, on 10/25/04
at 08:06 PM, Rich Grise <rich@example.net> said:

As should those who covertly attach spying equipment to a respectable,
private individual's car...

Or any individual's car, in a country where the constitution is still in
force.

I am not aware of any country where the Constitution is still in force.
Can you enlighten us as to which ones you refer to?

John

 

[Paul Burridge]

On Mon, 25 Oct 2004 20:15:46 GMT, "Clarence" <no@No.com> wrote:

Can't function without a GPS, lets see? we didn't need one for the past
200,000,000 years.

Quite, although itinerant human tribes haven't been wandering about
for anything like *that* long.
I know Rich is only being humorous, but anyone who relies on one of
these things to tell them how to get from A to B obviously doesn't
know where they're going and shouldn't be on the road at all. It's
probably therefore safe to assume they don't have a driving licence,
either.

--

"What is now proved was once only imagin'd." - William Blake, 1793.