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Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

theguardian.com

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Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#181

Post by Jenda_ »

bmicraft wrote: post #44
saalweachter wrote: post #36

Earlier quoted context omitted.

The Active Denial System, listed on your link, causes pain by heating water in the skin. What is the proposed system for getting microwaves past the skin into the brain without creating the same effect as the ADS?

Using longer wavelengths should do exactly that.

Longer wavelengths require huge antennas to concentrate the energy at a distance. It would be probably very difficult to perform this attack. I also think that such energy density with relatively low frequency (~3 GHz) would disturb operation of computers, phones and other electronics, so it would be pretty suspicious.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#182

Post by Jenda_ »

nabla9 wrote: post #48
mensetmanusman wrote: post #29

Earlier quoted context omitted.

Yes, https://en.m.wikipedia.org/wiki/Directed-energy_weapon 2.4 GHz is used to heat your food in the microwave. Pulses that increase the fluence by an order of magnitude or more could probably boil water for a microsecond inside the brain and cause some strange reactions. What is unproven though, is how one would ever shrink the size of an electronic weapon like this.

Microwave transmitters are not that big. 4 kW generator or 100 kW pulse generator fits into a suitcase. What you need is a horn antenna that directs the beam from the distance, across the street for example. It's also possible to have multiple horns around the target. Only in the intersection of the beams the radiation reaches dangerous levels.

Horn antennas have radiation pattern tens of degrees wide, so it's difficult to target one room across the street. I'm not sure intersecting a few of them helps, maybe by a factor of two or so.

Back of the envelope math: per Wikipedia: "The gain of horn antennas ranges up to 25 dBi, with 10 - 20 dBi being typical." Let's say you are transmitting 4 kW with a 20 dBi horn, thus having 400 kW EIRP. At a distance of 15 meters, the energy spreads across a sphere of 4PI15^2 = 2800 m^2, for an energy density 140 W/m^2. So yes, this indeed exceeds health limits (in .cz: 50 W/m^2 for workers, 10 W/m^2 for civilians) and is kind a lot.

On the other hand, having a 400 kW EIRP source anywhere nearby should be immediately obvious to a NSA or probably anyone with almost any radio receiver, the interference would be terrible.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#183

Post by Jenda_ »

mensetmanusman wrote: post #29
bArray wrote: post #28

Are microwave attacks something that is proven to exist? Can we replicate the effects on mice from some distance? Given the fact they pass through walls, this kind of bounds the frequency range the attacks could exist in... I would expect to see radio interference on nearby devices, etc (even if operating on a different frequency). I wouldn't be entirely surprised if these could be self-manifesting symptoms from peop…

Yes, https://en.m.wikipedia.org/wiki/Directed-energy_weapon 2.4 GHz is used to heat your food in the microwave. Pulses that increase the fluence by an order of magnitude or more could probably boil water for a microsecond inside the brain and cause some strange reactions. What is unproven though, is how one would ever shrink the size of an electronic weapon like this.

Do you have any sources regarding the effect of pulses, e.g. in animal studies? Most materials I have found are dealing with average/CW power. (I work with weather radars, so I was doing some research recently to find out what I should do to not die)

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#184

Post by stjohnswarts »

ben_w wrote: post #71
nabla9 wrote: post #63

Earlier quoted context omitted.

Have you noticed how microwave cooking is not warming up the skin any faster than the insides? The wavelength is selected so that it penetrates and warms water molecules. It would cook your insides according to their water content. Surface of the skin has less water than tissue inside, so you would feel pain beneath the skin.

MythBusters tested that, the outsides (of food) heat up first.

Yeah this is why I usually get better results a 70% or so setting rather than 100% as it gives the heat a chance to spread a bit better than nuking at full power.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#185

Post by tsimionescu »

whereis wrote: post #126
tsimionescu wrote: post #113

Earlier quoted context omitted.

Its never reasonable to agree with the opaque conclusions of spy agencies in any country, especially when the conclusion points the finger at a hostile pwoer. There is literally no reason to believe public communications from a spy agency against their enemies (note: that does not mean that they can't be true, it just means that the truth of them is never the reason why the communication is put out).

This presumes a conspiracy amongst officers forced into early retirement to create a convincing false narrative. What reason would the USIC have for lying about this? It seems unlikely that we would ever retaliate in kind, especially not after bringing attention to these incidents.

What reason would they have for telling the truth? A spy agency's official communications are always meant to elicit some response, it is never simply to disclose some information, since their default mode is to hoard information.

In this case, their motive is obviously to create an image of Cuba as a devious enemy of the United States who is willing to hurt low level officers in chronic ways, a dishonorable enemy.

This probably comes in the context of generally improving relationships with Cuba on almost the entire American continent, while the USA is still maintaining its illegal embargoes.

Now, is it possible that they chose to use a true story to advance this narrative? Yes, it is, absolutely. But if they want to spread this message and don't have a true story they are willing to share, nothing would stop them from sharing a false one instead.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#186

Post by Johnythree »

Google234 wrote: post #2

Why don’t they install detectors inside all the embassies at risk to prove or disprove this? Why didn’t they do this earlier? I’m pretty sure there are many places that could be contracted to make a detector in a few weeks - this isn’t new technology. This seems really easy to test... so why are we still speculating.

So much this!

Any radio beam which was strong enough to affect human tissue would drive a basic EM detector crazy.

A suitable detector would be a simple wire dipole, a schottky diode and a meter. Any radio hobbyist could make you one in a few minutes.

Plus such a strong field would drive most domestic electronics equipment crazy due to our crappy RF immunity regulations..

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#187

Post by tsimionescu »

whereis wrote: post #156
l332mn wrote: post #147

Earlier quoted context omitted.

> What reason would the USIC have for lying about this? There's an entire industry revolving around blaming geopolitical enemies of wrongdoing without evidence, where the intelligence community plays a key part. This is done in order to control the narrative, steer the public perception and to keep a semblance of adherence to international law, in order to justify unilateral political, economic or military hostility.…

again, what specifically would the US be trying to justify with such a false narrative around rew's? Not seeing the cost/benefit.

Their continued unilateral embargo of Cuba, deemed illegal by the UN, needs some constant justification. Especially in light of Cuba's diplomatic efforts in the rest of the world (most recently, dispatching Cuban doctors to help care for Covid19 patients all over the world, starting with the outbreak in Lombardia).

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#188

Post by tsimionescu »

whereis wrote: post #157
macinjosh wrote: post #143

Earlier quoted context omitted.

Throwing off other intelligence agencies. These people never deal in the truth that’s the whole game.

It's categorically false to say intel agencies (or the slight "these people") never deal in truth. That is not how misinfo/disinfo works. Additionally, intel agencies play an integral role in providing truthful and accurate products, for govt and industry partners.

It would be more correct to say that they never deal in truth with the public. Of course they are a source of well researched and painstakingly obtained truths for government decision makers, but never for the public.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#189

Post by Johnythree »

reedf1 wrote: post #39

Can't you just get a spectrum analyser to detect things like this? Did technology like that not exist in this era?

Yes, and it wouldn't need to be a sensitive spectrum analyser.

If the RF field is strong enough to affect human tissue, then a crude broadband RF detector would do the job.

Something as simple as a wire dipole and a schottky diode with a meter.

Plus in such a strong field, most of your domestic electronics equipment would be going crazy. Just like a mobile phone near a blue tooth speaker.

Re: Havana syndrome: NSA officer’s case hints at microwave attacks since 90s

#190

Post by Johnythree »

koonsolo wrote: post #116

I remember a US embassy where they had all kinds of antennas in the attic, to spy on communication. Is it possible that Cuba is trying to block the spectrum so they can't use this technique?

Easy to filter out the microwave jammer.

How do you think radio comms work on a warship equipped with high power radars?

Or even on a domestic airliner?

And of course if it were happening, the communications techs would be well aware of it.

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