On Wed, May 5, 2021, 4:26 PM coderman <[1]coderman@protonmail.com>
   wrote:

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     hello Karl, replies in the clear below, as usual :)
     ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
     On Wednesday, May 5, 2021 11:14 AM, Karl <[2]gmkarl@gmail.com>
     wrote:
     >
     > I have some books digitally archived, but with a focus on
     shielding
     > rather than covert communications...
     this is EMSEC (emissions security)
     you can play with it youself, speaking of SDR :P
       [3]https://github.com/martinmarinov/TempestSDR

   Your challenge is to understand things well enough to do this with an
   rtl-sdr, which is quite possible given a screen refreshes so many times
   per second.
   If you can do that, you can make a commonplace device that reveals the
   displays of surrounding other devices.  This will get people actually
   acting on this severe issue, rather than pretending it is safer to hide
   it.
   Try to sniff something else too, so people don't think that encrypting
   and shielding their display signals resolves the situation.  We need
   shielded spaces to do secure work in, or we do not have a democracy, in
   this digital age.

     the set of references, sources, and external links on wikipedia
     is also a fount of information:
       [4]https://en.wikipedia.org/wiki/Tempest_(codename)

   Woah either I've never visited that article before or it's been
   improved a lot in the past few years!

     enjoy!
     best regards,
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References

   1. mailto:coderman@protonmail.com
   2. mailto:gmkarl@gmail.com
   3. https://github.com/martinmarinov/TempestSDR
   4. https://en.wikipedia.org/wiki/Tempest_(codename)