Comment by danbruc
1 year ago
Fun fact, you can actually detect semiconductor devices even if they are powered off and hence emit no radiation unless the design took specific precautions. This works by illuminating a region with high frequency electromagnetic radiation and then listening for the effects that PN junctions have on the reflected radiation due to their nonlinearity. [1]
[1] https://en.wikipedia.org/wiki/Nonlinear_junction_detector
> Thousands of diodes were mixed by the Soviets into the building's structural concrete, making detection and removal of the true listening devices by its American occupants nearly impossible.
Wow ...
I wonder if it would be feasible, with modern techniques and sufficient motivation, to map where the “background” diodes ended up setting in the concrete; then to measure newer sweeps against that baseline.
That's called playing the long game, and playing it quite cleverly!
Not really. It makes it clear from the first attempted sweep they altered construction -- the opposite of a long game.
3 replies →
Several days ago, a long interview with the former Czech ambassador to Moscow, Vítězslav Pivoňka, appeared in Czech newspapers. Unfortunately it is mostly paywalled. [0]
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...
Yeah!
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.
> our homes and offices have false positives littered all over the place
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.
2 replies →
> useful in most environments today because our homes and offices have false positives littered all over the place
Like the structural elements in your house/apartments have something similar to diodes in them, or what are you referring to?
2 replies →
Here [1] are some pictures and additional details on NLJDs. You can get your own, for example the Orion 2.4 [2] for USD 15.2k (free shipping) [3].
[1] https://www.cryptomuseum.com/df/tscm.htm#nljd
[2] https://reiusa.net/nljd/
[3] https://spyassociates.com/orion-2-4-non-linear-junction-dete...
Oh good, I really wasn't prepared to pay the $7 for shipping that.
Are nonlinear junction detectors still state-of-the-art for detecting hidden devices when powered off? Does anyone know if alternatives like electronic noses (to detect chemical signatures associated with IC packaging) and magnetic anomaly detection increasingly used for this?
[flagged]