Author Topic: Cell phones and aluminum foil  (Read 12309 times)

Monkeyleg

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Cell phones and aluminum foil
« on: January 16, 2012, 12:17:41 PM »
I was watching "Conspiracy Theory" last night. It's one of my favorite movies, not necessarily because it's great, but also because I love watching the incredible repertoire of facial expressions that Julia Roberts has.

Anyway, Mel Gibson has his apartment lined with aluminum foil. In other conspiracy movies, I've seen aluminum foil. I've also seen something like Faraday cages, as with the copper wire mesh cage that Gene Hackman uses in "Enemy of the State".

Just for fun, I wrapped my cell phone in aluminum foil, called it, and it didn't ring. I set up a number to be called, wrapped the cell phone in foil again, felt for the send button and hit it, but nothing. It didn't send a signal.

Then I tried the same thing with my cordless phone, but it didn't work. No matter how far I had the phone from the base station, it would ring. If I set it up to call, wrapped it in foil, then hit the send button, it sent the signal.

I'm just curious now. Why would the cell phone not be able to send or receive a signal, but the cordless can? I would think that the cell phone would require a more powerful sending/receiving device.


French G.

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Re: Cell phones and aluminum foil
« Reply #1 on: January 16, 2012, 12:41:25 PM »
Different freq is my guess. I've been thinking on this. I trac-phone now, but under my real name. I know now you can register it under any name, but association patterns would doom you, so any anon phone cannot call numbers you normally call, at least not more than once. Not paranoid enough to pop my battery all the time yet, but I figure a pre-paid flip phone is low-tech enough to drive passive monitors nuts. I did however cut the RFID chip out of my credit card, microwave it and trash it. Card works fine on the mag strip, getting sniffed, not so much.
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Zardozimo Oprah Bannedalas

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Re: Cell phones and aluminum foil
« Reply #2 on: January 16, 2012, 01:13:05 PM »
Quote
Different freq is my guess
Yep. Different frequencies penetrate barriers better or worse than others, like radiation.

PS: Also, power of a signal is a factor. Cell phone signals are weaker, since the transmission tower could be 20 miles away or more. Home wireless phones have less range from their base station, but work well within that range - since there is a strong signal.

Ben

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Re: Cell phones and aluminum foil
« Reply #3 on: January 16, 2012, 01:17:01 PM »
If you're trying to create a Faraday cage, you might also want to try wrapping the phone in something non-conductive before wrapping it in the foil.
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AJ Dual

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Re: Cell phones and aluminum foil
« Reply #4 on: January 16, 2012, 02:22:50 PM »
If you're trying to create a Faraday cage, you might also want to try wrapping the phone in something non-conductive before wrapping it in the foil.

And run a grounding lead from the foil wrapper to a cold water pipe, etc.
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MillCreek

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Re: Cell phones and aluminum foil
« Reply #5 on: January 16, 2012, 02:33:54 PM »
This thread is relevant to my interests but fails to answer the most pressing question:

Should I be wearing a tinfoil or copper mesh hat?   [tinfoil]
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Quote from: Angel Eyes on August 09, 2018, 01:56:15 AM
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Ben

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Re: Cell phones and aluminum foil
« Reply #6 on: January 16, 2012, 02:35:58 PM »
This thread is relevant to my interests but fails to answer the most pressing question:

Should I be wearing a tinfoil or copper mesh hat?   [tinfoil]

Copper mesh definitely, as it will be worth more for barter in the post-apocalyptic world.
"I'm a foolish old man that has been drawn into a wild goose chase by a harpy in trousers and a nincompoop."

roo_ster

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Re: Cell phones and aluminum foil
« Reply #7 on: January 16, 2012, 02:42:25 PM »
Copper mesh definitely, as it will be worth more for barter in the post-apocalyptic world.

And doubles as a colander when making spaghetti.
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Nick1911

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Re: Cell phones and aluminum foil
« Reply #8 on: January 16, 2012, 02:57:43 PM »
Copper mesh definitely, as it will be worth more for barter in the post-apocalyptic world.

Just make sure to size the mesh appropriately.  Nothing more annoying then having to redo your mesh hat when "they" increase the mind control frequencies and it starts to slip through.

AJ Dual

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Re: Cell phones and aluminum foil
« Reply #9 on: January 16, 2012, 03:03:09 PM »
OT, but not so OT, that it deserves it's own thread. Seeing as this does use a smartphone to work.

http://www.hotray-info.de/

I am now on the hunt for a good strong source to see if I can confirm this works and the calibration is okay. Looking for some Uranium glass, old Fiesta-ware, etc.  Seeing as I paid $1.49 for the "lite" version, I'd like to know it can actually detect something.

Might have to wait until I get home from work and pry open an old smoke detector sitting in the workbench junk pile for the tiny sliver of Americium in it.  =D

(For those too lazy to click the link... You cover your phone's camera lens with a piece of black electrical tape, and you then touch the lens to things. If there's any strong betas or gammas, they excite the sensor array in the camera's CCD/CMOS element.)

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Monkeyleg

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Re: Cell phones and aluminum foil
« Reply #10 on: January 16, 2012, 03:23:41 PM »
Quote
And doubles as a colander when making spaghetti.

:D :D :D

So, what does the grounding wire do? And how does wrapping the phone in something non-conductive make the foil more like a faraday cage?

Sorry for all the questions, but I'm always curious about spy stuff in movies. I never know what's real or what's not. In "Enemy of the State", Gene Hackman takes the transmitters from Will Smith's clothes and puts them in a foil potato chip bag. If my home cordless phone was able to function wrapped and sealed in foil, why should I believe that state of the art NSA transmitters wouldn't work when in an unsealed foil bag?

Brad Johnson

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Re: Cell phones and aluminum foil
« Reply #11 on: January 16, 2012, 03:30:41 PM »

I am now on the hunt for a good strong source to see if I can confirm this works and the calibration is okay. Looking for some Uranium glass, old Fiesta-ware, etc.  Seeing as I paid $1.49 for the "lite" version, I'd like to know it can actually detect something.



Hit a pawn shop and see if they have an old watch with a lumenescent face or hands.

Also, see if you can find overseas-produced gas mantles.  Coleman no longer uses throrium in their lantern mantles (IIRC they switched to yttrium) but many overseas producers still do.  Problem is thorium emits mostly alphas so that may not help your 'speriment.

*edit to add*

Go to your local scrap metal dealer.  Some may still have a hot stack awaiting disposal in their yard.

Brad
« Last Edit: January 16, 2012, 03:38:27 PM by Brad Johnson »
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AJ Dual

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Re: Cell phones and aluminum foil
« Reply #12 on: January 16, 2012, 03:41:23 PM »
:D :D :D

So, what does the grounding wire do? And how does wrapping the phone in something non-conductive make the foil more like a faraday cage?

Sorry for all the questions, but I'm always curious about spy stuff in movies. I never know what's real or what's not. In "Enemy of the State", Gene Hackman takes the transmitters from Will Smith's clothes and puts them in a foil potato chip bag. If my home cordless phone was able to function wrapped and sealed in foil, why should I believe that state of the art NSA transmitters wouldn't work when in an unsealed foil bag?

The grounding wire works... well, by grounding.

An antenna works by receiving RF waves, and those waves induce small electrical currents in the metal of the antenna, which the electronics of the device pick up and read. Conversely, an antenna transmits through modulated electricity being run into it, and it gives off RF waves.

Grounding the metal shield of a Faraday cage, be it a purpose built one of copper mesh, or home made from aluminum foil discharges any current the cage may pick up into the ground. Either from received RF from the outside world, that could get through to the device inside, or conversely, from the device inside getting out. It's not 100% necessary because a properly made Faraday cage should allow RF to flow around it, or keep any originating within it inside, (Like the idea of an airliner getting hit by lighting, passes around the plane, through the outer skin, leaving the inside alone) but it makes it more effective, especially if your Faraday cage is not optimal in terms of being complete, or the right materials, or the best possible shape.

Wrapping the electronic device in an insulator, or a confirmed air-gap on all sides prevents electrical contact between the Faraday Cage and the device in inside it. Especially if it has an exposed metallic conductive antenna. Because if that touches the cage, it just effectively becomes part of the device's antenna.

There's also more complicated issues with the size of the wavelength of the RF you're trying to block, in or out, and multiples of that wavelength and the distance between the emitter/detector and the sides of the cage as well. This also has to do with why a Faraday Cage can have "holes" in it, like use copper, or some other kind of mesh, because if the holes are smaller than the wavelength you're blocking, it acts as a solid sheet. (This is why you have the see through mesh in the door of your microwave.)

Most portable consumer electronics no longer have external metallic parts to them anymore, so insulation might not be needed, since the entire case and all exposed surfaces are often non conductive plastics. Although it's possible that even chrome-look plastic trim etc. might have enough metal contact to provide a pathway.

The capacitance/conductive glass of smartphones touch-screens might also be another path too.

Maybe birdman can fill in or correct anything I've said wrong, but that's my understanding of it.
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MillCreek

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Re: Cell phones and aluminum foil
« Reply #13 on: January 16, 2012, 04:10:48 PM »
So what you are saying is that my copper mesh skullcap should have a wire pigtail trailing on the ground.
_____________
Regards,
MillCreek
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Quote from: Angel Eyes on August 09, 2018, 01:56:15 AM
You are one lousy risk manager.

Hawkmoon

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Re: Cell phones and aluminum foil
« Reply #14 on: January 16, 2012, 04:38:28 PM »
Should I be wearing a tinfoil or copper mesh hat?   [tinfoil]

Yes.
- - - - - - - - - - - - -
100% Politically Incorrect by Design

Tallpine

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Re: Cell phones and aluminum foil
« Reply #15 on: January 16, 2012, 04:38:49 PM »
So what you are saying is that my copper mesh skullcap should have a wire pigtail trailing on the ground.

Better to attach it to a steel stake driven into the ground ;)
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griz

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Re: Cell phones and aluminum foil
« Reply #16 on: January 16, 2012, 04:40:34 PM »
This thread is relevant to my interests but fails to answer the most pressing question:

Should I be wearing a tinfoil or copper mesh hat?   [tinfoil]

You can't go wrong with tin foil.  Go with the proven technology.
Sent from a stone age computer via an ordinary keyboard.

MechAg94

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Re: Cell phones and aluminum foil
« Reply #17 on: January 16, 2012, 05:11:40 PM »
If you are going to wear a metal mesh hat, might as well make it out of good steel.  That way you not only protect yourself from mind control, but the chain mail protects against slashing blades. 
“It is much more important to kill bad bills than to pass good ones.”  ― Calvin Coolidge

AJ Dual

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Re: Cell phones and aluminum foil
« Reply #18 on: January 16, 2012, 05:16:51 PM »
So what you are saying is that my copper mesh skullcap should have a wire pigtail trailing on the ground.

No. That it should enclose your entire skull. RF could still leak in at your neck.
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Tallpine

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Re: Cell phones and aluminum foil
« Reply #19 on: January 16, 2012, 05:29:08 PM »
No. That it should enclose your entire skull. RF could still leak in at your neck.

Airtight is best  ;)
Freedom is a heavy load, a great and strange burden for the spirit to undertake. It is not easy. It is not a gift given, but a choice made, and the choice may be a hard one. The road goes upward toward the light; but the laden traveller may never reach the end of it.  - Ursula Le Guin

Monkeyleg

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Re: Cell phones and aluminum foil
« Reply #20 on: January 16, 2012, 06:07:13 PM »
But what about all of the various bugs that Gene Hackman, Jason Bourne, and countless other CIA/NSA/M5 types find in their shoes, and then disable by putting them in potato chip bags or in the microwave? Aren't there tons of different bugs being used by the spy agencies that use something other than RF transmitters? Aren't the movies full of it? (Dumb question, I know).

dogmush

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Re: Cell phones and aluminum foil
« Reply #21 on: January 16, 2012, 09:32:36 PM »
OT, but not so OT, that it deserves it's own thread. Seeing as this does use a smartphone to work.

http://www.hotray-info.de/

I am now on the hunt for a good strong source to see if I can confirm this works and the calibration is okay. Looking for some Uranium glass, old Fiesta-ware, etc.  Seeing as I paid $1.49 for the "lite" version, I'd like to know it can actually detect something.

Might have to wait until I get home from work and pry open an old smoke detector sitting in the workbench junk pile for the tiny sliver of Americium in it.  =D

(For those too lazy to click the link... You cover your phone's camera lens with a piece of black electrical tape, and you then touch the lens to things. If there's any strong betas or gammas, they excite the sensor array in the camera's CCD/CMOS element.)



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