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A comment on An Implementation of Tempest in GNU Radio. Parent comment

Re:An Implementation of Tempest in GNU Radio by jandrese on Wednesday May 13, 2020 @09:01PM (#23173908)
200dB is the one way freespace path loss to Geo orbit.

Back when I learned this I was shocked that satellite communications work at all.

I can only imagine how much loss you have trying to hear communications from the Voyager probes now.

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Re:An Implementation of Tempest in GNU Radio by drmpeg on Thursday May 14, 2020 @02:51AM (#23176252)
318 dB for Voyager 1 at X-band.
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Re:An Implementation of Tempest in GNU Radio by boredgamer2 on Thursday May 14, 2020 @08:48AM (#23178789)
> Back when I learned this I was shocked

Care to explain? I'm not following..

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Re:An Implementation of Tempest in GNU Radio by jandrese on Thursday May 14, 2020 @11:30AM (#23180721)
Every 3dB is roughly a halving of the power level. It's hard to wrap a human brain around the orders of magnitude difference, the numbers are so far outside of anything we can encounter in the human scale.

Still, I will try to make an analogy. Start with the smallest transistor we make today, (7nm) and scale it up by the equivalent of 200dB and it would be 258 million km across, or about the same as the diameter of the Earth's orbit around the sun.

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