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Old 26-07-2014, 18:37   #61
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Re: What will happen to you when gps goes down

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Originally Posted by Factor View Post
A GPS doesn't track you - you do understand that don't you, its not a transmitter, only a receiver. And the only information it receives is is the time signal from individual satellites.
The GPS satellites actually do transmit quite a bit more info than just time. You are correct, GPS receivers only receive, they don't transmit.

As for his assertion that he could transmit a spoofing signal, I'm kind of doubtful since he would need to know the secret W code in order to generate the correct P(Y) code. He could probably disrupt the incoming signal with a stronger signal on the same freq., but that would not spoof the receiver into thinking it was a specified distance from the correct location.
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Old 26-07-2014, 18:42   #62
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Re: What will Happen to you when GPS goes Down

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Finally - What is the term for someone who is making a logic argument but keeps pushing the boundary conditions to the point where their answer becomes valid? There is a precise term for it that escapes me.
Dan that is "Reductio ad absurdum" and it is the point an answer becomes ridiculous to accept, not necessarily valid or invalid btw. The scenario I was painting almost became reality 2 years ago, and may so again in the foreseeable future. That is not ridiculous. So it wasn't like your zombies, or end of the world apocalyptic scenario. Just a world without electrical devices (for a while). Why is that so hard for people to understand? My mother (who is still alive) remembers such a world on her farm. That was less than 100 years ago. And how long has mankind survived without electricity?
You may call me a loonie. I say you are unwilling to learn from history. This world that we have built is really quite fragile. And a microchip, wither on a satellite or in a GPS receiver, may be the most fragile of all.
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Old 26-07-2014, 18:45   #63
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Re: What will happen to you when gps goes down

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Originally Posted by socaldmax View Post
The GPS satellites actually do transmit quite a bit more info than just time. You are correct, GPS receivers only receive, they don't transmit.

As for his assertion that he could transmit a spoofing signal, I'm kind of doubtful since he would need to know the secret W code in order to generate the correct P(Y) code. He could probably disrupt the incoming signal with a stronger signal on the same freq., but that would not spoof the receiver into thinking it was a specified distance from the correct location.
Spoofing civilian GPS has been done. It was actual spoofing and not simply jamming of the signal, which is relatively easy. As a practical matter, the spoofing device must be near (line of sight) the GPS receiver being spoofed.

UT Austin Researchers Successfully Spoof an $80 million Yacht at Sea | News
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Old 26-07-2014, 18:59   #64
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Re: What will Happen to you when GPS goes Down

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Dan that is "Reductio ad absurdum" and it is the point an answer become invalid btw. The scenario I was painting almost became reality 2 years ago, and may so again in the foreseeable future. So it wasn't like your zombies, or end of the world apocalyptic scenario. Just a world without electrical devices (for a while). Why is that so hard for people to understand? My mother (who is still alive) remembers such a world on her farm.
You may call me a loonie. I say you are unwilling to learn from history. This world that we have built is really quite fragile. And a microchip, wither on a satellite or in a GPS receiver, may be the most fragile of all.
Newt - I didn't call anyone a loonie BTW...

I get there can be a disruption of service. One could plan for a 1 hour outage, a 5 day outage or a permanent outage.

Let's say the solar flare wipes out the electronics. I try one of 3-5 gps on board - they're out. Big deal. I know where I am. I know the general direction of a large landmass and I sail on.

If one want to argue that a gps user can't tell east from west using the sun at an approximate latitude than sure, that person probably should not be passage making.

That person is also least likely to make any effort in learning celestial nav.

The idea that when the GPS goes out "All is Lost" is ridiculous.

I would be more worried about the solar flare knocking out the electronics that control my charging, engine and power systems - especially if I rely on making water.

So how about mechanical charging system regulation as a backup as a higher priority. Maybe I should not leave shore without sufficient water tankage to survive 3 months at sea - yada, yada, yada...

The idea that one can (or should) plan for any eventuality is called survivalism. If one wants to be the "last man standing" on a desolate rock - good on ya. I prefer to stumble upon a south pacific island where coconuts fall outta trees and bananas grow wild. The good news is the zombies won't be able to find me (even if they could they can't swim - or so I am told)

Some folks are just not wired to obsess that deeply about it.

OTOH - In my scenario I become the "Fire God" that fixes the village hand pump and is proffered native women in reverence to my awesomeness and soon, "I AM KING OF ALL I SURVEY!"

(Hey if we're gonna make up scenarios I prefer ones where I live on a beach and bang native girls. You have your doomsday and I'll have mine.)
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Old 26-07-2014, 19:13   #65
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Re: What will Happen to you when GPS goes Down

Fair enough Dan. I just don't consider it Doomsday. Esp. not the scenario you have planned. For the natives to get dumb your going to have to wait for a generation or two- darn that public education.
I agree that not having water would be a bigger deal. Still a reason to navigate safely to a river/stream.
Its all good. I rig the boat the way I want, you rig yours your way.
I do still have cruising tanks btw. Wondered why I kept em.
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Old 26-07-2014, 19:20   #66
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Re: What will happen to you when gps goes down

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Hmm... please correct me if I'm wrong but wasn't it only the Omega transmitters that were shut down - thus limiting the full time availability of the system. I thought the VLF transmitters stayed on line, maybe not 24/7 but at least every time someone wanted to ask a sub to surface for a more intense chat via satellite - so grab a "quick" fix when ya can

However for the purposes of this crazy thread, my VLF / Omega long range nav unit will suit me very well as I do all the other stuff mentioned in order to hunt down Mark J and raid his home brew while the rest of the world destroys it's self

Yes, you're wrong. LOL

They shut down the Omega transmissions and destroyed several of the transmitters. Some of the transmitters are still used for VLF comms for subs, but your Omega receiver is not an RDF system, it used time delay calculations for a very rough, 4 mi accuracy fix.

Your Omega receiver is essentially an anchor, or at best a space heater. How good of one is food for a different thread.
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Old 26-07-2014, 19:25   #67
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Re: What will Happen to you when GPS goes Down

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Fair enough Dan. I just don't consider it Doomsday. Esp. not the scenario you have planned. For the natives to get dumb your going to have to wait for a generation or two- darn that public education.
I agree that not having water would be a bigger deal. Still a reason to navigate safely to a river/stream.
Its all good. I rig the boat the way I want, you rig yours your way.
I do still have cruising tanks btw. Wondered why I kept em.
Philosophically we are a pretty weird species. On one hand we crave the company of our tribe yet spend all out time complaining about anyone who doesn't share our exact philosophy. Not only that we will make it a life mission to convert the others.

BTW - still plenty of places with dumb natives. Even in America...
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Old 26-07-2014, 19:32   #68
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Re: What will happen to you when gps goes down

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Originally Posted by David M View Post
Spoofing civilian GPS has been done. It was actual spoofing and not simply jamming of the signal, which is relatively easy. As a practical matter, the spoofing device must be near (line of sight) the GPS receiver being spoofed.

UT Austin Researchers Successfully Spoof an $80 million Yacht at Sea | News
I didn't say it was impossible, just doubtful that he could do it.

I see from your article that it has been done, but it took a bit of effort and expense. They were also onboard the yacht they were spoofing. I just don't see it as being within the capabilities of "most" people, supervillains and well funded graduate students excepted, of course.
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Old 26-07-2014, 19:36   #69
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Re: What will Happen to you when GPS goes Down

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Newt - I didn't call anyone a loonie BTW...

I get there can be a disruption of service. One could plan for a 1 hour outage, a 5 day outage or a permanent outage.

Let's say the solar flare wipes out the electronics. I try one of 3-5 gps on board - they're out. Big deal. I know where I am. I know the general direction of a large landmass and I sail on.

If one want to argue that a gps user can't tell east from west using the sun at an approximate latitude than sure, that person probably should not be passage making.

That person is also least likely to make any effort in learning celestial nav.

The idea that when the GPS goes out "All is Lost" is ridiculous.

I would be more worried about the solar flare knocking out the electronics that control my charging, engine and power systems - especially if I rely on making water.

So how about mechanical charging system regulation as a backup as a higher priority. Maybe I should not leave shore without sufficient water tankage to survive 3 months at sea - yada, yada, yada...

The idea that one can (or should) plan for any eventuality is called survivalism. If one wants to be the "last man standing" on a desolate rock - good on ya. I prefer to stumble upon a south pacific island where coconuts fall outta trees and bananas grow wild. The good news is the zombies won't be able to find me (even if they could they can't swim - or so I am told)

Some folks are just not wired to obsess that deeply about it.

OTOH - In my scenario I become the "Fire God" that fixes the village hand pump and is proffered native women in reverence to my awesomeness and soon, "I AM KING OF ALL I SURVEY!"

(Hey if we're gonna make up scenarios I prefer ones where I live on a beach and bang native girls. You have your doomsday and I'll have mine.)



OK, "Fire God."

Now throw in a 13 month old baby projectile spewing at both ends, and let's see how fast you hit that EPIRB button.

LOL
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Old 26-07-2014, 19:57   #70
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Re: What will Happen to you when GPS goes Down

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Fair enough Dan. I just don't consider it Doomsday. Esp. not the scenario you have planned. For the natives to get dumb your going to have to wait for a generation or two- darn that public education.
I agree that not having water would be a bigger deal. Still a reason to navigate safely to a river/stream.
Its all good. I rig the boat the way I want, you rig yours your way.
I do still have cruising tanks btw. Wondered why I kept em.
I respectfully disagree with your assertion that we'll have to wait.

I humbly submit that somebody has to be watching Jerry Springer, Dr Phil, Maury Povitch, Steve Wilkos, the "Real Housewives of..." and all of the "reality TV" shows, not to mention wrestling. Yes, it's fake.

When a TV show gets renewed season after season with the plot line of a young girl showing up with 5 guys and the results of a paternity test to determine who the father is, I have pretty good evidence that we are already doomed. The double digit IQ group is reproducing at a rate far greater than the triple digit IQ group, much less the college graduates.
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Old 26-07-2014, 20:02   #71
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Re: What will Happen to you when GPS goes Down

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OK, "Fire God."

Now throw in a 13 month old baby projectile spewing at both ends, and let's see how fast you hit that EPIRB button.

LOL
Me + Boat + 13 Month Old Baby = Your Argument Is Invalid...

Some things actually are impossible.
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Old 26-07-2014, 20:03   #72
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Re: What will Happen to you when GPS goes Down

But do you know who the Kardashians are?
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Old 26-07-2014, 20:15   #73
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Re: What will happen to you when gps goes down

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I know how to build a gps jammer that I can use on a vessel to make it appear in a different location or shut it down all together. :



...get a length of sturdy material and use as a baseball bat to twat the antenna off its mount? ..an easy build!
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Old 26-07-2014, 20:15   #74
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Re: What will Happen to you when GPS goes Down

Tune in Sackvill NS?
Seriously, I never venture far enough from land that I can't find my way to some dirt with no more than the sun, a compass or the north star... might not be exactly the dirt I was looking for, but dirt it would be!
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Old 26-07-2014, 20:16   #75
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Re: What will Happen to you when GPS goes Down

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But do you know who the Kardashians are?
Don't they own a cable channel or something?
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