7 ms·

No, it sounds like a telescope focusing onto a single pixel (i.e. just the back of the curtains), and then using the output from this pixel with a lock-in ampli

No, it sounds like a telescope focusing onto a single pixel (i.e. just the back of the curtains), and then using the output from this pixel with a lock-in amplifier tied to the broadcast signal. The sensitivity would be enormous due to the lock-in. With a CRT you would be able to do this with <microsecond resolution as the scan lines went across. In today's LCD world, I guess something similar could be done for a whole pixel-average of a whole frame, and then look at the time-series of that to correct for lag in digital television / internet etc..

henryfjordan 7y ago
So it's using a telescope and a camera to see what's going on in your house (albeit hopefully in a very limited way)... In the US that'd be an illegal search without a warrant.
- umvi 7y ago
  In the US no one cares if you buy a TV and set up some rabbit ears or whatever you want with it, especially not the government
  - beenBoutIT 7y ago
    The only things we (Americans) allow our government to exercise that amount of control over are psychoactive drugs/plants and female reproductive rights. With things like AR15s or TVs we require unfettered access with no paper trail, but if you want Adderall you'll need 3-sheet triplicate DEA forms and it's a federal crime in all 50 states to possess a growing number of naturally occurring plants and fungi.
    - pacaro 7y ago
      Not to mention lawn darts or kinder eggs
      - jessaustin 7y ago
        Us kids always made lawn darts for ourselves with scrap rebar and an old chopsaw with a cracked switch that shocked you...
    - umvi 7y ago
      This is an inflammatory comment. "Naturally occurring plants" are illegal in all of the EU as well. Also it's a logical fallacy[2]. Lots of naturally occurring things can have very bad effects on society. Caster beans are natural (and legal). Should we allow people to grow and process them and sell ricin by the vial - after all, it's a naturally occurring protein, right? Should we allow people to grow, process, and sell naturally occurring anthrax bacteria? [1] https://news.ycombinator.com/item?id=20643883 https://news.ycombinator.com/item?id=20643883 [2] https://en.wikipedia.org/wiki/Appeal_to_nature https://en.wikipedia.org/wiki/Appeal_to_nature
      - beenBoutIT 7y ago
        Close reading clears up a simple misunderstanding; "The only things we (Americans) allow our government to exercise that amount of control over are psychoactive drugs/plants and female reproductive rights..." Ricin has nothing to do with female reproductive rights and isn't known to be psychoactive.
- FireBeyond 7y ago
  To look in your open window, even with a telescope? I don't think that is considered illegal.
  - dsr_ 7y ago
    In California, Penal Code 647(j): (1) A person who looks through a hole or opening, into, or otherwise views, by means of any instrumentality, including, but not limited to, a periscope, telescope, binoculars, camera, motion picture camera, camcorder, or mobile phone, the interior of a bedroom, bathroom, changing room, fitting room, dressing room, or tanning booth, or the interior of any other area in which the occupant has a reasonable expectation of privacy, with the intent to invade the privacy of a person or persons inside. This subdivision does not apply to those areas of a private business used to count currency or other negotiable instruments.
    - ceejayoz 7y ago
      I think you're really misinterpreting that. All the example places given are ones you'd likely be frequently undressed. I'm not sure I'd argue I have an expectation of privacy in the living room with the curtains open - people walking on the sidewalk by my house see in mine all the time.
    - criddell 7y ago
      If it's just a sensor on the other end of the telescope then it's not a person.
    - otterley 7y ago
      Attorney here! (Not providing legal advice - consult a licensed attorney in your jurisdiction.) You're trying to leverage a "peeping Tom" law to frustrate law enforcement, and that is unlikely to succeed. The key qualifier here is "with the intent to invade the privacy of a person or persons inside." Law enforcement activities are unlikely to satisfy this prong.
      - t0astbread 7y ago
cryptonector 7y ago
If you delayed the program onto your TV/laptop/whatever by some number of seconds, that surely would defeat the detector, though, of course, the detector could look for this. A better way to defeat it would be to play two programs on the same or two TVs near each other, then the two signals would interfere in a way that should confuse the detector. Blackout curtains (which I recommend for other reasons), would work best though.
marcosdumay 7y ago
It could have a <1Hz signal encoded on the average brightness of the screen. It does look like something crazy that could be made to work reasonably well with a lot of polishing.

henryfjordan 7y ago

So it's using a telescope and a camera to see what's going on in your house (albeit hopefully in a very limited way)... In the US that'd be an illegal search without a warrant.

umvi 7y ago
In the US no one cares if you buy a TV and set up some rabbit ears or whatever you want with it, especially not the government
- beenBoutIT 7y ago
  The only things we (Americans) allow our government to exercise that amount of control over are psychoactive drugs/plants and female reproductive rights. With things like AR15s or TVs we require unfettered access with no paper trail, but if you want Adderall you'll need 3-sheet triplicate DEA forms and it's a federal crime in all 50 states to possess a growing number of naturally occurring plants and fungi.
  - pacaro 7y ago
    Not to mention lawn darts or kinder eggs
    - jessaustin 7y ago
      Us kids always made lawn darts for ourselves with scrap rebar and an old chopsaw with a cracked switch that shocked you...
  - umvi 7y ago
    This is an inflammatory comment. "Naturally occurring plants" are illegal in all of the EU as well. Also it's a logical fallacy[2]. Lots of naturally occurring things can have very bad effects on society. Caster beans are natural (and legal). Should we allow people to grow and process them and sell ricin by the vial - after all, it's a naturally occurring protein, right? Should we allow people to grow, process, and sell naturally occurring anthrax bacteria? [1] https://news.ycombinator.com/item?id=20643883 https://news.ycombinator.com/item?id=20643883 [2] https://en.wikipedia.org/wiki/Appeal_to_nature https://en.wikipedia.org/wiki/Appeal_to_nature
    - beenBoutIT 7y ago
      Close reading clears up a simple misunderstanding; "The only things we (Americans) allow our government to exercise that amount of control over are psychoactive drugs/plants and female reproductive rights..." Ricin has nothing to do with female reproductive rights and isn't known to be psychoactive.
FireBeyond 7y ago
To look in your open window, even with a telescope? I don't think that is considered illegal.
- dsr_ 7y ago
  In California, Penal Code 647(j): (1) A person who looks through a hole or opening, into, or otherwise views, by means of any instrumentality, including, but not limited to, a periscope, telescope, binoculars, camera, motion picture camera, camcorder, or mobile phone, the interior of a bedroom, bathroom, changing room, fitting room, dressing room, or tanning booth, or the interior of any other area in which the occupant has a reasonable expectation of privacy, with the intent to invade the privacy of a person or persons inside. This subdivision does not apply to those areas of a private business used to count currency or other negotiable instruments.
  - ceejayoz 7y ago
    I think you're really misinterpreting that. All the example places given are ones you'd likely be frequently undressed. I'm not sure I'd argue I have an expectation of privacy in the living room with the curtains open - people walking on the sidewalk by my house see in mine all the time.
  - criddell 7y ago
    If it's just a sensor on the other end of the telescope then it's not a person.
  - otterley 7y ago
    Attorney here! (Not providing legal advice - consult a licensed attorney in your jurisdiction.) You're trying to leverage a "peeping Tom" law to frustrate law enforcement, and that is unlikely to succeed. The key qualifier here is "with the intent to invade the privacy of a person or persons inside." Law enforcement activities are unlikely to satisfy this prong.
    - t0astbread 7y ago

cryptonector 7y ago

If you delayed the program onto your TV/laptop/whatever by some number of seconds, that surely would defeat the detector, though, of course, the detector could look for this. A better way to defeat it would be to play two programs on the same or two TVs near each other, then the two signals would interfere in a way that should confuse the detector. Blackout curtains (which I recommend for other reasons), would work best though.

marcosdumay 7y ago

It could have a <1Hz signal encoded on the average brightness of the screen. It does look like something crazy that could be made to work reasonably well with a lot of polishing.