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A Faraday cage is not a jammer. As the article points out: > Faraday cages are different from electronic jamming devices, which work by actively blasting out a

by dalke 10y ago

A Faraday cage is not a jammer. As the article points out: > Faraday cages are different from electronic jamming devices, which work by actively blasting out an electromagnetic signal that stops someone from receiving radio waves. > Those jamming devices are illegal, but Faraday cages don't break the law, seeing as they passively filter out phone signals - although you can imagine that blocking all phone reception at the pub isn't something that would go down particularly well. The article also points out, "You most likely have a type of Faraday cage in your house right now in the form of your microwave. That metal mesh you can see in between the glass in the door is there to stop microwaves from escaping." Any metal container acts as a Faraday cage, including metal vessel hulls. Obviously these are not all banned by the law you pointed out, which only applies to a wireless telegraphy station, or wireless telegraphy apparatus.

onion2k 10y ago
Building a Faraday cage specifically to block phone signals is a very different act compared to building a Faraday cage. It's the "to block phone signals" bit that makes it illegal.
- dalke 10y ago
  Here is the law: http://www.legislation.gov.uk/ukpga/2006/36/section/8 http://www.legislation.gov.uk/ukpga/2006/36/section/8 It refers to "telegraph station" and "apparatus". A Faraday cage is not a telegraph station, so it must be an apparatus to be covered under that law. What does that mean? I think it's defined in http://www.legislation.gov.uk/uksi/2016/426/regulation/3/made http://www.legislation.gov.uk/uksi/2016/426/regulation/3/mad... : > “apparatus” means any finished appliance or combination of appliances, liable to generate electromagnetic disturbance, or the performance of which is liable to be affected by such disturbance, and which generates, or is designed to generate, or is liable to generate fortuitously, electromagnetic energy at frequencies not exceeding 3,000 gigahertz and includes— > (a) components or sub-assemblies intended for incorporation into an apparatus by an end-user, which are liable to generate electromagnetic disturbance, or the performance of which is liable to be affected by such disturbance; > (b) mobile installations defined as a combination of apparatus and, where applicable, other devices, intended to be moved and operated in a range of locations; Are you arguing that a Faraday cage is a "finished appliance or combination of appliances"? And it "generates, or is designed to generate, or is liable to generate fortuitously, electromagnetic energy"? If not, then it is not an apparatus, and so not regulated under the law you pointed to. If you still think it is illegal, then please cite the actual law, and not some commentary about the law, as commentaries are more open to misinterpretation.
  - wlesieutre 10y ago
    It generates electromagnetic energy in the same sense that noise cancelling headphones generate sound. The net effect is that it interferes destructively with the original incoming waves, never adding on to them. Whether that legally counts as generating interference, I have no idea. (all that assuming I actually understand how Faraday cages work) Addendum: maybe "generates" isn't the right word, since noise cancelling headphones make their own sounds from a power source, while this is totally passive redirection. You wouldn't say a mirror generates light, after all.
    - dalke 10y ago
      Your addendum is correct. A Faraday cage is much more like a passive mirror, or sound absorbing foam, than it is an active, powered, noise cancelling headphones.
- DanBC 10y ago
  Please could you cite the relevant English law?
- Retric 10y ago
  Hardly, you need to block phone signals to do a range of research and development for the next generation of phones / cellular networks. Clearly the intent was not to block such research.
pavel_lishin 10y ago
> "The use of any apparatus, whether or not wireless telegraphy apparatus, for the purpose of interfering with any wireless telegraphy I highlighted the important bits. Hammers aren't illegal either, unless you're using them to smash out headlights.
- dalke 10y ago
  "Apparatus" is defined at http://www.legislation.gov.uk/uksi/2016/426/regulation/4/made http://www.legislation.gov.uk/uksi/2016/426/regulation/4/mad... . That definition does not include walls or hammers. Also, that quote that you repeated does not come from the actual law, but is an interpretation the law for those curious about phone jammers. See my comment at https://news.ycombinator.com/item?id=12238960 https://news.ycombinator.com/item?id=12238960 for a link to the law.
  - deleted 10y ago
    [deleted]

by dalke 10y ago

onion2k 10y ago

Building a Faraday cage specifically to block phone signals is a very different act compared to building a Faraday cage. It's the "to block phone signals" bit that makes it illegal.

dalke 10y ago
Here is the law: http://www.legislation.gov.uk/ukpga/2006/36/section/8 http://www.legislation.gov.uk/ukpga/2006/36/section/8 It refers to "telegraph station" and "apparatus". A Faraday cage is not a telegraph station, so it must be an apparatus to be covered under that law. What does that mean? I think it's defined in http://www.legislation.gov.uk/uksi/2016/426/regulation/3/made http://www.legislation.gov.uk/uksi/2016/426/regulation/3/mad... : > “apparatus” means any finished appliance or combination of appliances, liable to generate electromagnetic disturbance, or the performance of which is liable to be affected by such disturbance, and which generates, or is designed to generate, or is liable to generate fortuitously, electromagnetic energy at frequencies not exceeding 3,000 gigahertz and includes— > (a) components or sub-assemblies intended for incorporation into an apparatus by an end-user, which are liable to generate electromagnetic disturbance, or the performance of which is liable to be affected by such disturbance; > (b) mobile installations defined as a combination of apparatus and, where applicable, other devices, intended to be moved and operated in a range of locations; Are you arguing that a Faraday cage is a "finished appliance or combination of appliances"? And it "generates, or is designed to generate, or is liable to generate fortuitously, electromagnetic energy"? If not, then it is not an apparatus, and so not regulated under the law you pointed to. If you still think it is illegal, then please cite the actual law, and not some commentary about the law, as commentaries are more open to misinterpretation.
- wlesieutre 10y ago
  It generates electromagnetic energy in the same sense that noise cancelling headphones generate sound. The net effect is that it interferes destructively with the original incoming waves, never adding on to them. Whether that legally counts as generating interference, I have no idea. (all that assuming I actually understand how Faraday cages work) Addendum: maybe "generates" isn't the right word, since noise cancelling headphones make their own sounds from a power source, while this is totally passive redirection. You wouldn't say a mirror generates light, after all.
  - dalke 10y ago
    Your addendum is correct. A Faraday cage is much more like a passive mirror, or sound absorbing foam, than it is an active, powered, noise cancelling headphones.
DanBC 10y ago
Please could you cite the relevant English law?
Retric 10y ago
Hardly, you need to block phone signals to do a range of research and development for the next generation of phones / cellular networks. Clearly the intent was not to block such research.

pavel_lishin 10y ago

> "The use of any apparatus, whether or not wireless telegraphy apparatus, for the purpose of interfering with any wireless telegraphy I highlighted the important bits. Hammers aren't illegal either, unless you're using them to smash out headlights.

dalke 10y ago
"Apparatus" is defined at http://www.legislation.gov.uk/uksi/2016/426/regulation/4/made http://www.legislation.gov.uk/uksi/2016/426/regulation/4/mad... . That definition does not include walls or hammers. Also, that quote that you repeated does not come from the actual law, but is an interpretation the law for those curious about phone jammers. See my comment at https://news.ycombinator.com/item?id=12238960 https://news.ycombinator.com/item?id=12238960 for a link to the law.
- deleted 10y ago
  [deleted]