6 ms·

Instead of shutting it down couldn't he put the miner in a faraday cage?

• jeremyt 9y ago
  Cages only block external em, they don't block internal em from getting out.
  • NateyJay 9y ago
    Yes they do. A Faraday cage is equally good at blocking radio waves going out as coming in. They don't protect against conducted emissions though - along a power cable for example - so they're not a complete solution.
    • sterlind 9y ago
      Perhaps the radiation wasn't mostly coming from the Antminer box itself - each 700Mhz clock the rig draws current, the transformer propagates it back to the wall, and the power lines in the flat become a big antenna. Powerline Ethernet has this problem, but it uses only a 25MHz carrier wave, so it only bothers hams.
  • ofcourseianal 9y ago
    https://en.m.wikipedia.org/wiki/Faraday_cage https://en.m.wikipedia.org/wiki/Faraday_cage “Faraday cages are also used to enclose devices that produce RFI, such as radio transmitters, to prevent their radio waves from interfering with other nearby equipment.”
  • bdonlan 9y ago
    Sure they do, that's how microwaves avoid heating people standing nearby. However, getting the power in without letting the RFI escape the power connections is the tricky bit.
    • AstralStorm 9y ago
      Not too tricky, the right transformer or ferrite coil with active PFC is good enough. Of course that would increase the bill. The fault is on FCC side for approving borderline power supplies.
  • deleted 9y ago
    [deleted]
  • hatsunearu 9y ago
    A lot of EM phenomena is symmetric, and this one's not an exception
  • jsjohnst 9y ago
    So explain how you can stand next to your microwave then? Did you think the size of the holes in the metal mesh of the window was consistent across all microwaves by coincidence?
  • tgb 9y ago
    While people are pointing out your mistake, it's worth bringing up the fact you were certainly thinking of: when it comes to static electric fields, a Faraday cage complete protects the interior from external charges but does nothing to shield the interior from the external charges. However, we are considering non-static electric fields and in particular ones at high frequencies. However, I think the fact that the Faraday cage is not symmetric when it comes to static electric fields is very interesting. Ask yourself this: how does the cage know what "inside" versus "outside" means? You know the old joke where a mathematician has to enclose the greatest area with a given fence and so she takes the fence and wraps it around herself and declares "I am outside the fence." Well, why can't I declare myself to be inside the Faraday cage and suddenly get the benefits of its shielding? You might say that the difference is that the outside has the "boundary" of the universe and that makes it distinct from the inside. [1] But we don't yet know that the universe isn't finite and wrapped up on itself spatially, so if that were the difference, then isn't a Faraday cage experimental evidence in favor of the universe not being finite? I think therein lies the answer: if we wanted to actually use this as an experiment, we would have to place a charge outside of the Faraday cage and wait for sufficiently long time that the electric field is effectively static. However, for our experiment to work, we would have to wait so long that the electric field becomes static on the scale of the entire universe. And so no, the Faraday cage is not an experiment we can practically perform to measure the shape of the universe and the difference is the obvious one: the exterior is the larger one and is simply just "big enough" that we can't ever wait for the EM fields to settle down in the exterior like we can on the interior. [1] Mathematically, this come in as the fact that the Poincare lemma https://en.wikipedia.org/wiki/Closed_and_exact_differential_forms https://en.wikipedia.org/wiki/Closed_and_exact_differential_... requires a "contractible" domain. The exterior of the cage is not contractible, so we are not guaranteed to be able to use the integral forms of Maxwell's equations over the exterior of the cage. However, the interior is contractible.
    • ofcourseianal 9y ago
      “Faraday cage complete protects the interior from external charges but does nothing to shield the interior from the external charges” What are you on about?
• TuringNYC 9y ago
  That would seriously crimp the profit margins, and probably make heat dissipation more difficult.
  • s0rce 9y ago
    A metal mesh shouldn't compromise heat dissipation or forced air cooling.
  • flashman 9y ago
    The notice[1] says it was operating in the 700 MHz band. The wavelength for this band is 42.9cm. A few sources I found (StackExchange, Anandtech) say a Faraday cage is effective with a mesh 1/20th the wavelength. Surrounding the device with metal containing 2.1cm (0.85in) holes would probably work and only require minor modifications to support heat dissipation. Side note, now everyone knows Victor Rosario in Brooklyn probably has a bunch of cryptocurrency... [1] https://transition.fcc.gov/Daily_Releases/Daily_Business/2018/db0215/DOC-349258A1.pdf https://transition.fcc.gov/Daily_Releases/Daily_Business/201...
    • krallja 9y ago
      > Victor Rosario in Brooklyn probably has a bunch of cryptocurrency... At 1155 GH/s, he has probably mined upwards of several dozen dollars worth of cryptocurrency this month. And an extra hundred dollars on his power bill, assuming it’s not included in his rent.
      • kerkeslager 9y ago
        Brooklyn apartments this time of year are often poorly heated. If you're paying for the electricity to run a space heater, it might as well produce bitcoins.
        • quickthrower2 9y ago
          Heat pumps are more efficient. A miner makes an inefficient heater.