5 ms·

I don't get the physics of how it could possibly be a microwave weapon. Microwaves (mostly) just heat things up. Even the area denial "giant microwave generato

by xxpor 6y ago

I don't get the physics of how it could possibly be a microwave weapon. Microwaves (mostly) just heat things up. Even the area denial "giant microwave generator" on a truck weapons simply make you feel like you're burning up. How could they possibly find a frequency or modulation that A) Only affects the brain B) Isn't stopped by exterior walls C) Doesn't cause heating effects on the rest of the body (and everything else around you, or at least between you and the source of the radiation) D) Isn't incredibly obvious when it's sitting around. Either this would have to be fairly high power, i.e. physically large, or it would have a high gain antenna (also large). If the power is low, it'd have to be close to the victim, like in the same room. The other problem is how do you hide the antenna? It can't sit in a van because the metal exterior would attenuate it.

admiralspoo 6y ago
It depends on the frequency. The brain is mostly water, but there are clear differences in the dielectric constant of air, the skull (bone) and the sweet delicious gray matter inside the cavity. By tuning the frequency of the waves, you can set up resonances in the cavity. For a related effect, see https://www.youtube.com/watch?v=wCrtk-pyP0I https://www.youtube.com/watch?v=wCrtk-pyP0I
- xxpor 6y ago
  Hm resonance inside the skull isn't something I'd considered, that's a fair point.
  - CamperBob2 6y ago
    Because it's not an issue. A bag of saltwater makes a really terrible resonant cavity.
    - emmelaich 6y ago
      You'd think grapes would make a poor resonant cavity too. But you can create plasma with grapes in a microwave oven.
      - the_only_law 6y ago
        Before I act like an idiot and go do this, is there any significant safety risk or major risk to the equipment in doing this?
        CamperBob2 6y ago
        Should be fine as long as you put a cup of water in the microwave alongside the grape. They aren't really meant to run empty, and microwaving a single grape would be basically running it empty.
      - CamperBob2 6y ago
        Yes, and that's precisely because they are so lossy. It's not a resonant effect. You're just taking advantage of the grape's cross section being roughly a quarter-wavelength at 2.4 GHz, which allows the magnetron to dump a ton of power into it. It's analogous to using a couple of forks to operate a pickle from 120V.
        MacsHeadroom 6y ago
        >roughly a quarter length Is that not resonance?
        CamperBob2 6y ago
        The same thing would happen with an ideal resistor whose leads formed a dipole of the right length, so no.
- ajsnigrutin 6y ago
  Due to skin effect, most of the power is absorbed in the outer layers (skin mostly), and that causes 'warm/hot/burning' feeling, before doing anything else to your body.
  - K0balt 6y ago
    That's not what the "skin effect" refers to, and penetration of tissue / heating is completely dependent on frequency.
- 01100011 6y ago
  From the report: "Frey reported these symptoms with an RF source transmitting at 1.3GHz(which provides the greatest absorption depth into cortical tissue)..." So they are implying that not all RF is stopped by the skin and some does penetrate deep enough to reach the brain. I don't suppose it will be long until some shortsighted YouTuber tries this as the experiment would not be hard to replicate at all.
derefr 6y ago
Collimated microwaves (i.e. a maser) pointed directly at the skull, from a distance, through a window, I'd assume. What are the reported symptoms from military radio engineers standing in the transmission path of high-power/long-distance ship-to-ship microwave links?
- xxpor 6y ago
  Trying to align a microwave link on a ship that's floating (i.e. not completely steady) sounds like a horrible nightmare.
- ajsnigrutin 6y ago
  To directly point radiwaves, you need very very high frequencies, and with skin effect, those don't go very deep into a humans head (we're talking millimeters or less here).
  - kurthr 6y ago
    You mean like into ears? I mean that's the reported symptom... your ears are your skin so are your eyes.
infoseek12 6y ago
I can’t address many of your objections but I don’t think putting it in a van would be a problem. Organizations sometimes use fiberglass body panels that look like normal metal ones but are transparent to RF in these kinds of situations.
- nitrogen 6y ago
  Not that it's proof or anything, but supposedly ICE or a similar org has undercover backscatter XRay vans. Don't remember where I read that, but it was years ago.
  - ceejayoz 6y ago
    Definitely a thing. The NYPD has them as well. https://www.propublica.org/article/drive-by-scanning-officials-expand-use-and-dose-of-radiation-for-security-s https://www.propublica.org/article/drive-by-scanning-officia... > ABC News reporters Richard Esposito and Ted Gerstein provide one of the few accounts of the backscatter van in a book they wrote chronicling a year inside NYPD's bomb squad. Describing the security ahead of President Bush's motorcade to the 2004 Republican convention, they wrote that every vehicle entering the street in front of the hotel was ordered to drive between two unmarked white vans, which X-rayed each vehicle for bombs.
    - janekm 6y ago
      Driving between two vans suggests that it's not back-scatter though... "Just" low energy x-ray probably?
- elihu 6y ago
  I sort of assumed that if this is an RF weapon the attackers would just have a hotel room directly above or below the intended target, maybe even some structural modifications to the floor/ceiling.
sudosysgen 6y ago
It's complete bullshit. If there actually were RF attacks of such huge intensities, the US would have trivially recorded them. Yet that didn't happen. I don't see any reason why no measurements and proof would be measured given the extreme ease of doing so, except that it just didn't happen.
- Sporktacular 6y ago
  "US would have trivially recorded them." Depends on the frequency range being continuously monitored. If it's above the usual signals intelligence range there's a good chance it wouldn't have been recorded. "Yet that didn't happen." And we wouldn't know if it had. Holding on to what you can detect and attribute carries advantages too.
  - sudosysgen 6y ago
    We're talking about repeated attacks at around 1.4Ghz, so not only within the range of SIGINT, but it would literally fry your phone, and they were supposedly repeated. As for the last one, if there was proof, then the State Department wouldn't abandon the theory, and such wildly speculative and substance-less research wouldn't be commissioned.
lend000 6y ago
All 4 of your points could be easily explained if the device was designed similar to a "gamma knife" [0]. With a gamma knife, a number of lower power beams converge on the target from different locations to create a higher intensity at a calculated location, and everywhere else the intensity is low enough to write off. [0] https://en.wikipedia.org/wiki/Radiosurgery#Gamma_Knife https://en.wikipedia.org/wiki/Radiosurgery#Gamma_Knife
- jellicle 6y ago
  But now the problem is convincing large numbers of people to stick their head into a machine where 200 individual beams can be focused on their skull, and then forget they ever did so. https://www.mayoclinic.org/tests-procedures/brain-stereotactic-radiosurgery/about/pac-20384679 https://www.mayoclinic.org/tests-procedures/brain-stereotact...
- bjourne 6y ago
  But for neurosurgery the head is held in place and the gamma knife does not need to be hidden. Presumably, the microwave transmitters of a conjectured gamma knife would need to be portable and able to operate without even being in the same room as the target's head.
  - ruined 6y ago
    Microwaves have much lower energy than gamma radiation, and brain damage requires much cruder fidelity than brain surgery. The experience described by targets seems to indicate room-scale effects.
    - bjourne 6y ago
      We're still taking about imagined devices pinpointing targets' brains from large distances and through walls. I find it hard to believe that these devices would be that accurate and never miss and, say, accidentally hit someone's eyes or neck and cause obvious tissue damage.
- sudosysgen 6y ago

by xxpor 6y ago

admiralspoo 6y ago

It depends on the frequency. The brain is mostly water, but there are clear differences in the dielectric constant of air, the skull (bone) and the sweet delicious gray matter inside the cavity. By tuning the frequency of the waves, you can set up resonances in the cavity. For a related effect, see https://www.youtube.com/watch?v=wCrtk-pyP0I https://www.youtube.com/watch?v=wCrtk-pyP0I

xxpor 6y ago
Hm resonance inside the skull isn't something I'd considered, that's a fair point.
- CamperBob2 6y ago
  Because it's not an issue. A bag of saltwater makes a really terrible resonant cavity.
  - emmelaich 6y ago
    You'd think grapes would make a poor resonant cavity too. But you can create plasma with grapes in a microwave oven.
    - the_only_law 6y ago
      Before I act like an idiot and go do this, is there any significant safety risk or major risk to the equipment in doing this?
      - CamperBob2 6y ago
        Should be fine as long as you put a cup of water in the microwave alongside the grape. They aren't really meant to run empty, and microwaving a single grape would be basically running it empty.
    - CamperBob2 6y ago
      Yes, and that's precisely because they are so lossy. It's not a resonant effect. You're just taking advantage of the grape's cross section being roughly a quarter-wavelength at 2.4 GHz, which allows the magnetron to dump a ton of power into it. It's analogous to using a couple of forks to operate a pickle from 120V.
      - MacsHeadroom 6y ago
        >roughly a quarter length Is that not resonance?
        CamperBob2 6y ago
        The same thing would happen with an ideal resistor whose leads formed a dipole of the right length, so no.
ajsnigrutin 6y ago
Due to skin effect, most of the power is absorbed in the outer layers (skin mostly), and that causes 'warm/hot/burning' feeling, before doing anything else to your body.
- K0balt 6y ago
  That's not what the "skin effect" refers to, and penetration of tissue / heating is completely dependent on frequency.
01100011 6y ago
From the report: "Frey reported these symptoms with an RF source transmitting at 1.3GHz(which provides the greatest absorption depth into cortical tissue)..." So they are implying that not all RF is stopped by the skin and some does penetrate deep enough to reach the brain. I don't suppose it will be long until some shortsighted YouTuber tries this as the experiment would not be hard to replicate at all.

derefr 6y ago

Collimated microwaves (i.e. a maser) pointed directly at the skull, from a distance, through a window, I'd assume. What are the reported symptoms from military radio engineers standing in the transmission path of high-power/long-distance ship-to-ship microwave links?

xxpor 6y ago
Trying to align a microwave link on a ship that's floating (i.e. not completely steady) sounds like a horrible nightmare.
ajsnigrutin 6y ago
To directly point radiwaves, you need very very high frequencies, and with skin effect, those don't go very deep into a humans head (we're talking millimeters or less here).
- kurthr 6y ago
  You mean like into ears? I mean that's the reported symptom... your ears are your skin so are your eyes.

infoseek12 6y ago

I can’t address many of your objections but I don’t think putting it in a van would be a problem. Organizations sometimes use fiberglass body panels that look like normal metal ones but are transparent to RF in these kinds of situations.

nitrogen 6y ago
Not that it's proof or anything, but supposedly ICE or a similar org has undercover backscatter XRay vans. Don't remember where I read that, but it was years ago.
- ceejayoz 6y ago
  Definitely a thing. The NYPD has them as well. https://www.propublica.org/article/drive-by-scanning-officials-expand-use-and-dose-of-radiation-for-security-s https://www.propublica.org/article/drive-by-scanning-officia... > ABC News reporters Richard Esposito and Ted Gerstein provide one of the few accounts of the backscatter van in a book they wrote chronicling a year inside NYPD's bomb squad. Describing the security ahead of President Bush's motorcade to the 2004 Republican convention, they wrote that every vehicle entering the street in front of the hotel was ordered to drive between two unmarked white vans, which X-rayed each vehicle for bombs.
  - janekm 6y ago
    Driving between two vans suggests that it's not back-scatter though... "Just" low energy x-ray probably?
elihu 6y ago
I sort of assumed that if this is an RF weapon the attackers would just have a hotel room directly above or below the intended target, maybe even some structural modifications to the floor/ceiling.

sudosysgen 6y ago

It's complete bullshit. If there actually were RF attacks of such huge intensities, the US would have trivially recorded them. Yet that didn't happen. I don't see any reason why no measurements and proof would be measured given the extreme ease of doing so, except that it just didn't happen.

Sporktacular 6y ago
"US would have trivially recorded them." Depends on the frequency range being continuously monitored. If it's above the usual signals intelligence range there's a good chance it wouldn't have been recorded. "Yet that didn't happen." And we wouldn't know if it had. Holding on to what you can detect and attribute carries advantages too.
- sudosysgen 6y ago
  We're talking about repeated attacks at around 1.4Ghz, so not only within the range of SIGINT, but it would literally fry your phone, and they were supposedly repeated. As for the last one, if there was proof, then the State Department wouldn't abandon the theory, and such wildly speculative and substance-less research wouldn't be commissioned.

lend000 6y ago

All 4 of your points could be easily explained if the device was designed similar to a "gamma knife" [0]. With a gamma knife, a number of lower power beams converge on the target from different locations to create a higher intensity at a calculated location, and everywhere else the intensity is low enough to write off. [0] https://en.wikipedia.org/wiki/Radiosurgery#Gamma_Knife https://en.wikipedia.org/wiki/Radiosurgery#Gamma_Knife

jellicle 6y ago
But now the problem is convincing large numbers of people to stick their head into a machine where 200 individual beams can be focused on their skull, and then forget they ever did so. https://www.mayoclinic.org/tests-procedures/brain-stereotactic-radiosurgery/about/pac-20384679 https://www.mayoclinic.org/tests-procedures/brain-stereotact...
bjourne 6y ago
But for neurosurgery the head is held in place and the gamma knife does not need to be hidden. Presumably, the microwave transmitters of a conjectured gamma knife would need to be portable and able to operate without even being in the same room as the target's head.
- ruined 6y ago
  Microwaves have much lower energy than gamma radiation, and brain damage requires much cruder fidelity than brain surgery. The experience described by targets seems to indicate room-scale effects.
  - bjourne 6y ago
    We're still taking about imagined devices pinpointing targets' brains from large distances and through walls. I find it hard to believe that these devices would be that accurate and never miss and, say, accidentally hit someone's eyes or neck and cause obvious tissue damage.
sudosysgen 6y ago