Your TV can see through walls (2025)

thopterek

Thank you for more paranoia

ThePumpkinGod

So, a bad actor can now know when I'm at my house or not, I'm sure that's fine and won't be problematic

gbxyz

See also: Van Eck Phreaking https://en.wikipedia.org/wiki/Van_Eck_phreaking

fzeindl

Amazing book about similar topics: “Silence on the wire” by Michal Zalewski https://www.amazon.de/Silence-Wire-Passive-Reconnaissance-In...

walrus01

see also, presence detection of humans via wifi signals: https://arxiv.org/html/2308.06773v2

swerner

As anyone observed who had a TV with just basic analog terrestrial antennas, before cable and satellite dishes - it does make a difference to the signal, when and where you stand and countless pieces of physical comedy in TV shows incorporated that.

numlock86

Wait for people to learn about that you can listen in virtually anywhere through fiber-optic cables, as sound waves are enough to redirect the light in the cable to a measurable degree by "bending" the cable itself. Special devices to filter these variances out and transform them back to audio signals are a thing. It's only per line though, as any repeating device will just output a new cleaned up signal again. Oh well, there have always been ways to snoop on someone like that. Back in the day it was CRTs emitting measurable waves through the neighborhood, with some papers even going as far as restoring the displayed image through a wall. Nowadays it's fiber and WiFi, and those seem to be much easier to work with even. Plus everyone carries a device that is tracked by their mobile provider's cell network. shrug

1e1a

See these for a very low cost (<$10) method for observing WiFi and some LTE spectra: https://news.ycombinator.com/item?id=49922674 https://espargos.net/espsdr/

darkwater

Now, about the wifi part, why isn't there an Home Assistant extension that detects already room presence magically exploiting all of this??

armcat

Several years back we actually made use of the principle mentioned in this post, to more systematically count traffic on the roads [1]. In our case we used LTE/4G radio, and we could even estimate the direction of travel, as well as the type of traffic (pedestrian, small vehicles, large vehicles). It was more accurate than Google Maps because it was independent of the moving phone, i.e. it was "sensing the obstacles in the environment". [1] "Traffic Flow Estimation using LTE Radio Frequency Counters and Machine Learning", https://arxiv.org/abs/2101.09143

protocolture

Thats nothing, my old tv could predict incoming phone calls.

reactordev

I threw away all TVs in my house after the proliferation of ads on the Home Screen. Sorry, the only value a TV has is displaying images and audio at large sizes. Not getting me to shop. So I decided to get rid of them all and now I use large monitors and projectors. Make TVs dumb again.

blurbleblurble

IEEE ISAC, look it up

nubinetwork

I know this is written to sound scary, but it's been like this since the invention of the radio/telegraph (late 1800s?). You're getting blasted by rf almost continuously, unless you live in a bunker.

rapnie

Tangential. Of both LG [0] and Samsung [1] smart TV's it is known they spy on you any way they can. Does someone know if they do that too for models sold in Europe, which would likely be in violent breach of GDPR? [0] https://www.youtube.com/watch?v=6IFVTcM28KA (Gamers Nexus findings) [1] https://www.youtube.com/watch?v=VFx1DyAjxYc (LMGClips summary)

fortran77

There's no TV here. There's an ATSC broadcast signal and an SDR with a waterfall display.

doginasuit

I thought this article was going to be about putting a webcam on the other side of the wall and streaming through the TV, which somehow had never occurred to me and I want to try it now.

trafalgar_nah

Had to pull out my calculator to digest the calculations, phew. I'm a math major that's been out of the game for a bit, I guess i'm getting rusty.

closeparen

Our kitchen FM radio would reliably lose the signal of the local NPR affiliate whenever someone was halfway up the basement stairs. RF is weird!