Time to build a Faraday box

Trigger alert. The following subject matter is for those who understand that the Watercooler is a place where worldly topics get discussed sometimes. Please discontinue reading if the Watercooler is not the place you want to be. Thank you in advance.

Still here? OK:

When I was in Malaysia recently, there was building construction underway, where there were many scraps of metal lying around. Monks are allowed to take cast-off things without breaking Vinaya. I used one of these cast-off scraps to build a makeshift Faraday box (with the help of one of the stewards/kappiyas there). Radio signals cannot pass through metal. This is the “Airplane mode” that your smartphone truly deserves:

This is an aluminum box that took about 1 hour to hack together. The construction material used is called “Aluminum flashing”, which can be cut with tin snips.


That news report can’t possibly be true, considering the source. lol

lol i get ya.FoxNews?? But unfortunately i believe it is accurate.

What are you worried about Google getting, Venerable? Do you think they are going to whisk you away to some secret Google internment camp where they steal your robes and make you grow your hair long? Are you part of some clandestine inter-monastic network of cyber spies with a plan to zap people into the fourth jhana with your dhamma gun, so you can steal their stuff? :slight_smile:


This doesn’t make things any better.

Generally, if network connectivity is not possible, spyware on the phone store things locally. The next time you remove the cage and connect to a network, all the collected data will be sent to the Google mothership.


Smartphones are the spawn of the devil. :yum:

in so many ways, … amen? :joy:

Why Privacy matters:

Over the last 16 months, as I’ve debated this issue around the world, every single time somebody has said to me, “I don’t really worry about invasions of privacy because I don’t have anything to hide.” I always say the same thing to them. I get out a pen, I write down my email address. I say, “Here’s my email address. What I want you to do when you get home is email me the passwords to all of your email accounts, not just the nice, respectable work one in your name, but all of them, because I want to be able to just troll through what it is you’re doing online, read what I want to read and publish whatever I find interesting. After all, if you’re not a bad person, if you’re doing nothing wrong, you should have nothing to hide.” Not a single person has taken me up on that offer. - Glenn Greenwald in Why privacy matters - TED Talk

Also relevant:

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I never claimed that it was some kind of perfect solution. Only that it was ‘the “Airplane mode” that your smartphone truly deserves’:

Say one has on one’s phone writings on childhood experience one has survived… or erotic fantasy written for one’s spouse… or plans for one’s divorce or cancer treatment… or writing designed to work on one’s practice… or thoughts on how to help someone who came to you for counseling… or thought experiments of any kind.

Nothing illegal, all of it probably beneficial to many beings if allowed to continue without interuption distraction intimidation or betrayal of confidences …

J Edgar Hoover was gay. He kept that private. Should anyone never have the right to mental solitude???

I am thinking the Buddha would be a privacy supporter. Maybe there are references in the EBT?

I don’t like planes either. :yum:

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I have another mode that keeps me safe from a praying phone, I call it the “Leave the phone home” mode.

It doesn’t work everytime I need to go out, but it’s quite pleasant.

And I’ve extended this mode to my wallet and even keys :smiley: . So I travel lght when I’m not going far (which I rarely do nowadays).


The video shows that the data collection happens even if the phone is in “airplane mode”. Airplane mode presumably means that the cell phone function of the smart device is turned off. BUT as soon as you turn the cell phone back on the stored information can be transmitted.

Location information can come from several sources:

  1. GPS – which is built-in to most smart-phones and tablets.
  2. Cell phone towers – every tower has an id which can be plotted on a map. In a city a phone is getting signals from several towers at once which allows your general location to be calculated by triangulation.
  3. Inertial navigation – if the device knows which way you are holding it (portrait or landscape mode) then it probably has inertial sensors similar to the ones used for navigation in spacecraft, airplanes, submarines, ships and land vehicles.

More expensive GPS devices use a combination of GPS signals from satellites and inertial navigation.

None of those should be operational in airplane mode…

Yup, most mobile do have gyroscopes in them, and the are pretty well known quantity (millions of them built and shipped).

Which explains why Google could work out when someone is in a car (based on the acceleration, length etc) and can now when you are walking, sitting or lying down…

And you can’t turn that off.

If you sample the gyro 60 times per seconds assuming it provides a 2 bytes reading from the 3 axis you collect at most ~1.24 MiB per hour.

And that’s raw data, and it’s very easy to compress it because a lot of time the reading will be pretty much the same.

So, I guess the best option if you want to be free from such trouble is to leave the phone home. Because the gyro will still work in your pocket and box - no escape no matter how strong the mobile phone tin-foil hat is :smiley: .


It makes sense for a “airplane mode” to only turn off functions in the mobile device that use a radio transmitter.
GPS only requires a receiver. GPS may or may not be disabled, because it does not involve transmitting radio waves.

Hi @Feynman,

You are correcte. So it was my wrong assumption.

I checked my Android phone and I see that you can disable localisation at a global level (it immediately complains that no app using localisation will work)), but this is not part of the airplane mode…

Yes, you just need to receive, so it doesn’t need to be off in airplane mode. I have a Russian friend who told me that he once switched on his GPS navigation app while in an airplane. According to him, he got a severe telling off:

“You are travelling at 900 km/hour! You are speeding!”


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Apparently a foil-lined Potato chip bag will also work (the tin foil goes on the phone, not your head):

Man Used Potato Chip Bag To Skip Work For Two Years: Genius Or Slacker?

He stored his personal digital assistant, a device that acts as a GPS, in an empty foil packet of Twisties, a puffy cheese-based snack that is the equivalent of American Cheetos.


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Just because a software claims to do something doesn’t mean it actually does so. This is especially true of closed-source/proprietary software. Case in point, Windows 10 pretty much ignores the privacy switches you set and continues to send data to Microsoft servers including keystrokes:

Closed-source/non-free/proprietary software is loyal to it’s proprietors, not to the user.

Android phones may use most of the somewhat-free linux kernel but almost all the telecom firmware (wi-fi, carrier radio, gps receiver, etc) is non-free and closed meaning we really have no idea how it is programmed to behave.