Posted by RamboRogers 3 days ago
[1] https://en.wikipedia.org/wiki/Nonlinear_junction_detector
Wow ...
That happened due to the bugs found. This is the point I'm making. If your goal was to keep them where they were already are (Mokhovaya House) then the bag full of diodes mixed into the concrete did that perfectly for like 15ish years.
> They probably knew earlier than 1985.
Doesn't change that argument.
> So it probably wasn't a big deal and would've cost the SU a lot and they were less able to afford it.
We are talking about a few bags of diodes vs rebuilding three stories of the building with imported workers. This was a very cost efficient attack.
As you could expect, bugs everywhere, but some were used for intimidation. E.g. he says, on a weekend morning, we were still in bed with my wife, when a cuckoo started cuckooing out of a wall. Yeah, it was a bug, and it was meant to emit sound and make you more nervous: "we know about everything that happens in your bed".
He said that the Russians never cross the red line of actually physically manhandling diplomats, but as far as bugs and psychological pressure go, there is nothing off-limits.
[0] https://denikn.cz/1549047/deptali-ho-kukanim-a-ponizovali-ha...
It also makes me suspect that the device would not be super-useful in most environments today because our homes and offices have false positives littered all over the place. Such a countermeasure would be unnecessary now.
Sure, but location matters. Searching weird (for electronics to be), but line-of-sight places (like a bookcase) you might still have a good signal to noise ratio.
As I understand it clothes from Uniqlo have RFID tags in them.[0]
Like the structural elements in your house/apartments have something similar to diodes in them, or what are you referring to?
Note that other semi-conducting materials, such as a rusty nail or an oxidised piece of metal, also generate harmonic frequencies and may therefore cause an NLJD to generate a false positive.
https://www.cryptomuseum.com/df/tscm.htm#nljd
It turns out that the rectifiers in question were copper - cuprous oxide - lead sandwiches:
https://hackaday.com/2022/04/20/copper-rectifying-ac-a-centu...
[1] https://www.cryptomuseum.com/df/tscm.htm#nljd
[3] https://spyassociates.com/orion-2-4-non-linear-junction-dete...
2019, "Airbnb Has a Hidden-Camera Problem", 50 comments, https://news.ycombinator.com/item?id=24324300
2019, "How to find hidden cameras in your AirBnB", 300 comments, https://news.ycombinator.com/item?id=20457419
2023 repro of "Great Seal Bug" (1952): mechanical microphone, no power source, data exfiltrated via external directed microwave beam, https://www.youtube.com/watch?v=NLDpWrwijE8
Try measuring the RF emissions of:
USB hubs
AC power strips
SSD enclosures
monitors
Could a directional antenna help with locating RF sources? There's some older work ("WokFi") on parabolic antennas for WiFi, https://web.archive.org/web/20140802123553/http://www.usbwif...
Here's another circuit design for AD8317, https://g8rwg.uk/articles/noise-meter-ad8317/
> The AD8317 module I’m using has the logarithmic slope set to 22mV/dB. I used the output of a Viavi JD785 at different frequencies to check the slope and dynamic range of the device. Linearity and dynamic range at 1GHz and 3.5GHz is good and as expected drops off at 144MHz and 6GHz.
https://github.com/RamboRogers/rfhunter/blob/master/rfhunter... contains amazon links. About $100 although many of the required components come as packs.
Another approach is a phased rx array, could even be as few as 2 antennas, and from that you get a bearing too.
If you're going to go with that wide of a beam why not use a single element and wave it around?
I should also mention the third trade off, size, plays into this tool.
For others, probably just get an off the shelf TinySA?
Some paper and product references:
- (PDF) http://s3.amazonaws.com/arena-attachments/1381379/c3a4e75132...
- https://www.spycatcheronline.co.uk/product/camera-detector/
- https://www.ijser.org/paper/Lens-Detection-System-using-Opti...
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p4432023.m...
The optical camera detectors work based on a simple idea, red LED's are used to create a circular pattern of light and you look through a red filter at your space. A camera lens is concave and symmetric so it reflects the LED's in the same circular pattern. Blink the LED's. Look through the red filter and scan around the room. Anything that reflects a discernable circular blinking LED pattern is a lens or lens like. Basically it makes it easy to see everything that reflects light symmetrically back at you. Move around a little and anything with a lens will stand out. It only works with fairly large lenses though, a pinhole camera would not be detectable.
Their RF detectors have adjustable sensitivity and indicate amplitude of the signal. Good enough to track the transmissions back to the source, though they don't provide any frequency information. Range is somewhat limited so you have to move around a room to scan it.
TinySA works well for detecting RF sources also. I don't know what the exact update rate is but the one I have seems to update at least a few times per second. It's a little tedious to use, the RF spectrum is big and you'll find quite a few spikes from sources in it and you have to zoom in on each one to get the exact frequency and observe how it behaves (or maybe there is a way to select a peak of interest? I haven't played with it much.) You'll find FM radio stations, cellular communications, cordless phones, and lots more.
Most people are not going to be finding surveillance bugs in their homes or offices. However these things are useful for understanding what your RF environment is like or troubleshooting RF devices. Might be good for telling if your smart appliance is spying on you, for example if the detector beeps every time you change channels on your TV.
Sadly, hidden cameras, microphones or other forms of espionage in the workplace are rare but not unheard-of in the recent past, e.g. Wal Mart [1] or Lidl in Germany [2]. Any shop with a tradition of union-busting I'd assume to be filled with all possible sorts of surveillance by default. On top of that come the sex pest cases like [3] - and these have exploded in the last years now that tiny bugs can be had for tiny amounts of money on Alibaba and whatnot.
[1] https://en.wikipedia.org/wiki/Labor_spying_in_the_United_Sta...
[2] https://www.spiegel.de/wirtschaft/stasi-methoden-beim-discou...
[3] https://www.nn.de/erlangen/erlanger-chef-filmt-kolleginnen-m...
Of course, only a matter of time - if they don't already exist - before there's cheap spy cameras without a reflecting lens, like a solid state camera of sorts. I believe some years ago they were experimenting with that as an alternative to a front facing camera on phones.
https://www.beneaththewaves.net/Photography/Images/Thermal_I...
When I travel, I use mine to sweep the room.
I made a thermal camera https://github.com/RamboRogers/M5StickCPlus2-AMG8833-Thermal...
What's the frequency range and scanning speed of TinySA?
When I was a kid I used to hook a coil of wire and a diode to a piezo earphone. I then listened to the emissions of various devices in my house. My Amiga 500 was particularly interesting.
I ran across a few projects that do the same thing but add an opamp and recording so you can generate sounds for electronic music.
Isn't that effectively all the EMF? You may be missing a prefix.
Edit: huh, turns out these frequencies do have some applications: https://en.wikipedia.org/wiki/Super_low_frequency
In any case, I would want to detect the emissions from the CPU, memory bus and SD card traffic. Not all cameras are WiFi. Sure, that won't detect passive listening devices or other advanced techniques, but most people now are worried about video and that will have certain characteristic emissions.
Edit: Something like CamRadar, presented here: https://dl.acm.org/doi/10.1145/3569505
The phone camera will pick up the bright IR lights that hidden cameras use to illuminate the room-- wireless or not.
Obviously this only works if the camera uses IR lights, but pretty much all of the sneaky ones do.
That said, most of these spy cameras don't have IR illuminators...
Somewhere in my HN comment history from a while back is a response to a person claiming that modern phone cameras can’t detect IR illumination and remotes.
I took a bunch of modern iPhones and Android phones, from colleagues in an IT dept, and demonstrated they can in fact see a bunch of different IR remotes and illuminators with the rear camera.
I could find zero cameras that could not see the IR.
I’m not sure where people got the notion they couldn’t.
My cell phone's back camera will show IR light from IR remote controls (I've used it for just that to verify that a remote is transmitting). But I also have an outdoor IP camera with IR illumination in my back yard. The same cell phone camera sees zero IR emitted from the outdoor IP camera (even though it quite well lights up a fairly broad area of the yard at night).
So for my phone, if a 'spy cam' were using the IR wavelength the IP camera uses, I would never know it was present by using the phone camera. If it used something closer to the wavelength used by IR remotes, yes, then the 'spy cam' would light up via the phone camera.
I make IR devices. My phone is the only one in the warehouse that can pick up their emissions - everyone else's cameras have IR filters with what appears to be a sharp ~750nm cutoff. I'm the only one that will pick up 800-1064nm with my cheap Samsung, and so I'm the only one doing the testing on those diode assemblies.
I should also mention that both IR illuminators and TV remotes are usually either 850nm or 940nm, I have not looked into that aspect of it. I imagine that it's possible that your camera can detect one but not the other...
My Google Pixel 8a doesn't show anything on either camera, but my friend's front camera did! It shows up light purple.
Both front and rear cameras work.
The light shows up as a pinkish purple.
Thankfully the perverts who put this stuff in airbnbs just go to amazon and search and buy cheap stuff, which is easy to detect.
That's the main limit I see, but I'm wasn't sure if it such a device would still generate enough RF intrinsically w/o a radio.
Once a few common signals are known, the software could do programmed patterns to ferret out easy ones.
Every current carrying trace is an antenna.
In effect a camera into the RF world!
DIY radio telescope tuned to 2.4Ghz WiFi, https://www.youtube.com/watch?v=g3LT_b6K0Mc
Image of physical building overlaid with RF sources, https://www.facebook.com/thethoughtemporium/posts/2162600763...
> When I made the first video and photoshoped my impression of what I thought this would look like, I never imagined it would actually be this close. It's official, our telescope can map the wifi in a building as if it were any other form of light.
I imagine too that the other was not like the one. ;-)