Looking for a faraday bag that works

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catalekid

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I cannot seem to find a faraday bag or case for my cell phone. Sure, they are everywhere for sale at various prices but I have yet to find even one without negative reviews saying it doesn't work.

Do you know of one that works as it should?
 
Just put the phone in 'airplane mode'. (turn off all radios: cell, wifi, NFC and bluetooth.)

Poof, instant faraday cage.
 
If you are trying to protect the phone from a possible EMP putting the phone in airplane mode won't help. You still would need a faraday cage.

Well that might happen (maybe) but protecting the phone from EMP is, well, not very productive because if you DID have a nuke bust off over you in orbit or in the atmosphere around or above you the cell towers that you could hit with your phone anywhere within several hundred miles would likely be fried also.
 
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The most popular, practical, and valid reason anyone would need to RF shield a cellphone is to reduce the chance that it can be 'polled' or 'pinged' by Stingray type equipment. Secondary to that is cellphone tower triangulation. Either one will fail if the phone is in airplane mode (all radios shut off) or if it is totally shut off.

And if you leave the phone operating normally (cell radios on) while inside a faraday sleeve or bag, there can still be enough signal that leaks out to be 'seen' by the cell towers nearby.

Something I have noticed lately at least on some new android phones, there is a hidden setting that can override your desire to be in airplane mode, so the phone can look for wifi signals even when the wifi is turned OFF. So, while its possible for nearby wifi networks to 'see' your phone, they would need to be very close by, and if you look for the setting you can override that 'feature' and force the wifi to remain OFF.

For the other situation, if an EMP was strong enough to actually zap your cell phone into failure then the cellular system wont be working even if you have another phone you can retrieve that was in a faraday sleeve or bag.

EMP pulses typically are MOST effective on anything with wires attached. If your phone is hooked up to a charger it might get zapped, but if it was in your vehicle or even in your pocket, it will probably survive any EMP unless that EMP was SO strong that it incapacitated you and/or your vehicle.
 
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I cannot seem to find a faraday bag or case for my cell phone. Sure, they are everywhere for sale at various prices but I have yet to find even one without negative reviews saying it doesn't work.

Do you know of one that works as it should?
Just my two cents worth as an MFI developer (Made For iPhones). You don't need wires attached to be hit by pulse. And for sure, any form of communications that relies on electronics will fail, so regardless of what precautions you take, you may have a working radio/walkie talkie/cell phone, but unless you have capabilities to communicate to whatever distance is outside the damage zone, you won't have anyone to talk to....
If you want a simple and cheap way to prevent your cell phone from being communicated with or triangulated to, just go to the hardware store and buy some copper screening, enough to wrap around the phone twice, and hold it in place with elastic bands. Guaranteed to work, and cheap too. Airplane mode accomplished nothing much.
 
Airplane mode is effective to make your phone much less susceptible to unwanted RF interrogation or triangulation. I never said it was to prevent EMP damage. That topic came up later in the thread.

Also I did not say that only with wires attached your phone would be vulnerable, I indicated (and this is true) that when wires ARE attached it does make a device more vulnerable.

EMP pulses can travel long distances over electrical conductors and remain powerful enough to damage any electronic device attached. For instance if your phone was in a copper covering or any other kind of faraday sleeve, but it was hooked up to a charger plugged into the vehicle electrical system and/or a cell booster outside the vehicle, those conduction paths will render the faraday sleeve entirely useless, UNLESS the particular faraday sleeve employs 'EMP hardening' which will help bypass the EMP energy.

All of this is hypothetical since most of us will not be too worried about a cellphone if the cell network has been rendered inoperative in the case of a national emergency or nuclear attack.
 
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Here are a list of reasons to have your phone in a Faraday Bag:

"Mission Darkness™ faraday bags for keyfobs, cell phones, and small electronics block all wireless signals and keep devices shielded, preventing hacking, tracking, and chain of custody corruption. When a device is placed inside a bag, fob signals cannot be boosted, no apps or malicious code can be remotely triggered or wiped, no communication can penetrate, and no one can access the microphone, camera, GPS location, or data."
 
You can wrap your phone in newspaper a few times and put it in a pop-corn can, or any can with a well fitting lid, like the multitude of cute cans you find around Christmas.
As long as your phone does not touch the metal, you are good.
 
I know exactly what you mean about everything having at least some negative reviews. That kept me from buying one for a while, but then I decided to take a chance and I bought this one:

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$7 on Amazon

It works. I tested it a couple different times. It's made from very thin, light weight material, so it's hard to say how durable it would be over time, but it completely cuts off all radio signals in or out.
 
In the situation that law enforcement seizes a phone (as evidence or inventory) and inserts it into a faraday sleeve, they sure dont want someone remotely accessing, signaling, texting, pinging, polling, hacking, or wiping the phone, so yes, a smartphone might be ON and actively searching for tower signals and wifi signals while it's in a their 'chain of custody' faraday sleeve.

But for most people, if you insert your smartphone into a faraday sleeve while it is in normal mode, (meaning it is actively looking or pinging for a tower signal, and/or a wifi or bluetooth signal) why would you leave it in that mode, knowing the battery will drain quicker, AND you might drive right past a tower that the phone can very briefly 'see' and it will try to respond by transmitting a signal back to the tower...and it might even be 'seen' by the tower.

In other words, how does one verify the faraday sleeve is actually doing it's job UNLESS you test it by driving up fairly close to a tower? Then if you do get a text, for example, then you know at that point you had better turn it OFF while in the sleeve if you want it unreachable and invisible to the phone network.

And then again, if you plan to turn it off or use airplane mode while in the sleeve, then you really dont need the sleeve to begin with. Unless you are putting a spare or burner smartphone in the sleeve, turned OFF, as a spare for that 1 in 10 million chance that an N-EMP happens within 500 miles of you and maybe you might need a spare phone for taking pictures or maybe GPS use when you discover the world has gone SHTF.

Now YES...you can buy or build EMP bags and cases for OTHER electronic devices, such as generators, 2 way radios, cameras, c-paps, portable am/fm radios, etc etc, but NONE of these items are constantly trying to ping the local cell tower, so cutting off ALL exterior RF makes more sense.
 
Exactly what I was thinking. So many have written "I got this it works" "Do this it works, every time" "All you had to do is....." HOW YOU KNOW IT WORKS?

Just because sent $20 to a fancy web site does not mean what you got works. What have you done to make sure your super device actually provides you the protection you believe you are getting. Stuff claimed on the website is NOT enough proof.
I actually don't have a need for one, so it's not a big deal to me. I just wish folks had some backup to their claims.
 
..... In other words, how does one verify the faraday sleeve is actually doing it's job .....

..... HOW YOU KNOW IT WORKS?
You don't. Unless you have knowledge and access to sophisticated equipment you can't test it yourself. The best you can do is attempt to contact the phone in the protective bag. But that tells you nothing about what signals are leaking out.

If you don't know the wavelengths of the signals you are trying to block your best defense is a solid metal, properly constructed faraday cage. If you are real paranoid you need to remove the battery from the phone before putting into the cage.
 
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