Posted on 11/10/2013 8:53:33 AM PST by GunsAndBibles
Was given a new Android phone (loaded with Google programs) and realized I'm always being monitored, even when the phone is OFF. Looking for a signal blocking case/enclosure, similar to Faraday cage. Now off to the range, trying a new batch of .223 using IMR4227 and 62gr. SS109. Thanks for your input.
Right. But that was not the question. The question was “why do I have GPS when I’m off network?”
This is untrue.
Any conducting material with grid spacing significantly smaller than the wavelength of the signal to be attenuated is a Faraday Cage.
In particular, a metal box with thickness greater than the skip depth of the wave (which is no more than 100 microns or less) is always a Faraday Cage.
Grounding is required to avoid damage to objects outside of the cage, because induction currents induce charge on the outside of the box, which can be quite large if the signal has high energy. It does not affect the effectiveness of the cage as a shield. [I have demonstrated this to undergraduate physics and EE students, many times.]
Most of the phones don't have enough memory so they don't actually store the maps on the unit like a GPS nav unit. They have to connect into a network (via phone data or wifi) in order to download the map. So it is possible that your location information might be uploaded at that point.
Apparently there is map software that can be loaded on your phone like an app and then the phone could be a standalone GPS nav system.
Many, many years ago (around 1990) there existted hacker software which could find any mobile based on tower handshakes, and basically the handshake was as long as the phone had power. No GPS involved.
cardboard box, lined with tinfoil, no gaps, place inside.
Did you read my follow-up post #58?
It might have positive uses such as the police triangulating a person with dementia, or a child, or someone who has been kidnapped.
Also, the cell tower would have to know distance fairly accurately.
—— Your phone has a GPS receiver in it which is independent of the cellular network. The phone does report its location to the network when connected. -—
So even if I go into Settings > Location and disable all of the GPS services, my phone can still be tracked?
—— A metal box is not a Faraday cage unless the metal box is grounded. Otherwise it’s just a metal box -—
Does sitting on a concrete basement floor count? Or do you have to run a wire from it into the ground?
As I stated in my follow-up post #58, I tested this with an ammo can.
In this instance, the ammo can was sitting on an ungrounded kitchen counter.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.