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Testing Phone-Sized Faraday Bags

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Re: Testing Phone-Sized Faraday Bags

#121

Post by aurizon »

mcshicks wrote: post #102
formerly_proven wrote: post #22

Earlier quoted context omitted.

I think the biggest issue with cookie tin cans is that they usually don't close all the way around, because the lid or the box is always slightly oval and not round (they always "stick" just in two or three spots when opening), so it looks like there's a small gap around half the circumference long - far bigger than the wavelengths in question. Square tin can works better because those seem to usually scratch on the…

I had to do some testing with ble temp sensors once we're I needed to isolate them and then put them in a freezer. They were in advertising mode so I could tell at least if I could see them with a phone. A round tin that was used for green tea from Japan was the most reliable method I was able to improvise. It fit very snug and the lid was about an inch deep.

Yes, a one inch compressed gap like that is a tortuous attenuative path in it's own right...

Re: Testing Phone-Sized Faraday Bags

#122

Post by cevn »

wilkommen wrote: post #116
sdoering wrote: post #100

Earlier quoted context omitted.

I agree that the free market is easily gamed and therefore I really am glad to be living in a country with relatively strong consumer protection laws. I buy online, I can return within two weeks no question asked. It breaks within two years - I return it. Either I get a repaired one or a new one or my money back. There are few exceptions but mostly it makes shopping quite secure. Yes. There are bad actors. Yes people…

What country do you live in?

Sounds like something in EU to me.

Re: Testing Phone-Sized Faraday Bags

#123

Post by comeonseriously »

I think they could have done a better job with the aluminum foil. It looks rather not well done. He could have made a pouch and folded the sides over a few times.

I made a pouch for my car's key fob with aluminum foil and metal tape. It isn't as pretty as the ones you can buy, but it wasn't $25 either and It has worked really well.

Re: Testing Phone-Sized Faraday Bags

#124

Post by adolph »

pdkl95 wrote: post #103
adolph wrote: post #85

Earlier quoted context omitted.

> The average hotel room in any medium/large hotel chain probably includes a shaker as a standard item as part of the minibar. Maybe the hotels you stay in, Bond, James Bond.

I admit the vast majority of my experience with hotels consists of a single repeated data point: the staff[1] suite(s) we shared in the Hilton attached to the SJ convention center. They always had glasses/shaker/etc. You could probably ask for a shaker from roomservice or the hotel bar, if necessary. [1] If you registered for FanimeCon 2000-2011, the weird software you had to use was my fault...

She's not an average ship, Jim!

Re: Testing Phone-Sized Faraday Bags

#125

Post by JacobThreeThree »

14 wrote: post #113
pdkl95 wrote: post #15

I really like Snowden's recommended Faraday cage for phones or other devices of similar size: two drink-shaker cups[1]. Drink shakers are cheap and widely available. The average hotel room in any medium/large hotel chain probably includes a shaker as a standard item as part of the minibar. The simple two-cup style (as seen in [1]) is preferred over the fancier "strainer top" style because you can press the two cups t…

I think the issue is then you have to wait until you are already inside the hotel to use those shakers, which as others have said don’t actually exist in most hotels, and at that point you have been tracked to your exact location. Then it would be trivial to surveil you with other methods without needing your phone.

Pretty sure Google uses dead reckoning geolocation tracking when no signal is available. So as long as your phone is outside of the bag at some point, you're being tracked even when the phone is in the bag, and Google can correct any errors in their dead reckoning calculations once a signal is found.

Re: Testing Phone-Sized Faraday Bags

#126

Post by IncRnd »

This article was a fun read, and it really highlights how we trust the words on the tin to be accurate and not mistaken marketing gibberish.

However, the part about the cost ranging from $40 - $80 is simply not true. I know this, because I purchased for $20 yesterday a faraday box to hold my auto key fobs and my cell phone. [1] There are very many items for sale at this price point, fabric, pouches and boxes.

[1] https://smile.amazon.com/s?k=faraday+box

Re: Testing Phone-Sized Faraday Bags

#127

Post by pbhjpbhj »

wilkommen wrote: post #116
sdoering wrote: post #100

Earlier quoted context omitted.

I agree that the free market is easily gamed and therefore I really am glad to be living in a country with relatively strong consumer protection laws. I buy online, I can return within two weeks no question asked. It breaks within two years - I return it. Either I get a repaired one or a new one or my money back. There are few exceptions but mostly it makes shopping quite secure. Yes. There are bad actors. Yes people…

What country do you live in?

2 years is minimum default warranty by law in EU.

In the UK we have a warranty period with no particular limit, undergirded by the EU 2 year default, through the Consumer Rights Act -- basically it's founded on how long products would be reasonably expected to last, a fridge should last a decade, a cheap toy arguably far less.

But, I've had a problem with this that I think it's a useful example: Steam sold me a defective game, I tried to play it but the bugs ultimately made it impossible to enjoy (the purpose of entertainment!). Under the CRA digital goods are explicitly included in the ability to return when defective; but Steam/Valve decided their rules on "play" time trumped UK law. PayPal provided a refund (tiny amount of money) in accordance with their terms, but now Steam have taken revenge (the employee time spent on the issue certainly cost more than the original purchase), threatening to close, and then simply limiting my account. That should be illegal IMO, but I don't know if it is. I'm not going to pursue them at this point.

Imagine if a fast-food outlet said "if you complain about your food we'll ban you from buying from us", that would have a perverse effect on consumers and reduce the ability to push back against instances of low quality food. Sure, you can boycott them but that seems worse for everyone.

TL;DR at least in the digital domain, even with strong consumer protections companies can work around the law.

Re: Testing Phone-Sized Faraday Bags

#128

Post by RandallBrown »

SamuelAdams wrote: post #57

This is a super cool blog post. However I think it alludes to a much larger problem. For many products today, it’s very difficult or impossible for most people to verify the product works. For a network switch, there are free and open source tools like iPerf to test and verify speeds are as advertised. For a faraday box, you have to go through all these steps (and knowledge learned) just to be able to test these. Wha…

An easy solution would be putting your phone in the bag and have someone else call it.

The post does mention something similar near the bottom where they suggest putting an AirTag in the bag and seeing if your phone can find it.

Re: Testing Phone-Sized Faraday Bags

#129

Post by 24bug47 »

yosito wrote: post #101

I'd be curious if anyone finds it worthwhile to have a smartphone while being so paranoid that you have to hide it in a Faraday bag. I understand the problem. I just don't understand the practical use case: every time you use the phone, you have to take it out of the Faraday bag, and it can be used to spy on you or report information about you. Assuming you're keeping it in the Faraday bag all day, when and why would…

You would take out your phone if you would like to make a phone call, or check to see if you have received any messages. For the other 99% of your day, the IoT sensors being stuck on every conceivable object are unable to report back to HQ (and every agency and broker affiliated) your current whereabouts and trajectory.

Re: Testing Phone-Sized Faraday Bags

#130

Post by teddyh »

parkertomatoes wrote: post #72

I was hoping they would test chip bags, because it was a plot device in the most recent Terminator movie. After searching, I found that Kaspersky has a blog post on the topic: https://usa.kaspersky.com/blog/terminator-dark-fate-chips/18... It surprised me that chip bags were more effective in their test than cookie tins, but only when they double-bagged it

Also used in the, IMHO, underappreciated film Enemy of the State (1998).
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