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Comment Re:And is easily defeated... (Score 1) 357

Hrmm, doing the math, I'm not sure I can believe it. I'm still guessing that's the power at the transmitter and he was being a normal reporter, claiming the biggest numbers.

Here's some datar: http://www.physto.se/~ljvi4037/ProjectReferences/MillimeterWave%20Dosimetry%20of%20Human%20Skin.pdf

Assuming 1/32 penetration depth (95Ghz is more like 1/64), only 50% absorbtion (95GHz on forearm is around 70%), and he was made 100% out of water (best case scenario for maximum specific heat, and he might be a little sweaty) that's something like a 76 degree rise in temperature per second...I call reporter reporting big numbers type of bullshit.

Comment Re:Corner reflector (Score 1) 357

I think you should review the maths for a corner reflectors. In angle = out angle for, basically, the whole 90 degree opening, with a slight radial offset perpendicular with the beams direction. The most work would be figuring out which maybe 70 usable degrees segment to point the thing. With the size of it, and the fact that it requires line of site, do you really see this as a daunting task? Hey, tape two together! Now you have nearly 180 degrees! And, this isn't a laser beam...it spreads...you don't have to aim it precisely, and that would be the biggest problem! If it only works to 700m, you would have to be no more than 700m/2 for them to feel anything, and they'll always feel much less than half the pain of anyone around you.

Comment Re:Wear Foil! (Score 1) 357

Grounding is unnecessary for reflecting something a few wavelengths larger than the frequency of interest. At 3mm, you'd be completely safe, and fairly dangerous, behind a sheet of tinfoil.

Grounding is 100% unnecessary for a Faraday cage. RF doesn't know or care what ground is...all it can see is changes in impedance.

Comment Re:16 hours? (Score 1) 357

No, the stress is not an issue. It's the operating temperature of the device that's the issue. It was calibrated at its operating temperature and so can't give NIST traceable results without running at its operating temperature. If what you're claiming is true, you literally wouldn't be able to make measurements for the first two hours. You can make measurements just fine, they just wont be as accurate. If you disagree, try it.

Comment Re:Development costs? (Score 2) 331

Libraries man. Make a single cloth simulator, use it for all cloth. Make a single skin texture builder, use it for all skin. Make a single face constructor, use it for all faces. Trees, rocks, pavement, buildings...everything. If you've ever played with a proper 3d rendering platform where you don't have to draw everything by hand, it becomes impressive what you can make with a small algo and a random number generator to feed to it.

Comment Re:Is SETI wasting its time? (Score 1) 90

>Planets are very poor reflectors. Not comparable.

Not comparable!??? From wikipedia:
"The average overall albedo of Earth, its planetary albedo, is 30 to 35%, because of the covering by clouds, but varies widely locally across the surface, depending on the geological and environmental features."

Just because one square inch of mirror reflects better than one square inch of planet surface does not mean the mirror will be more visible. Your positionable mirrors will still need to cover a surface area that's a pretty large fraction of a planet.

BUT unfortunately that's not how Kepler detects planets. Assuming the detectors can detect an increase in brightness as well as a decrease...you're going to need an array that's close to 100% reflective and exactly the size of a planet.

>What you do is point at a target, let fly, then point at the next target, let fly, etc

From wikipedia:
"While only about a dozen planets have been confirmed in the habitable zone, the Kepler spacecraft has identified a further 54 candidates and current estimates indicate that there are "at least 500 million" such planets in the Milky Way."

Either the transmitter or receiver will need to have a wide lobe...otherwise the probability of intercept is stupid low. If you could position your absolutely massive mirrors array at a rate of 1500 planets/second, you would, on your receiving planet, see a signal once every three days for 1/1500 of a second. Kepler can see something like 15 degrees, and requires DAYS of averaging to get something statistically useful. Seeing a 1/1500 second signal even with, literally, planet sized light blockers or reflectors isn't anywhere close to our grasp yet.

Not saying that some aliens aren't doing this....but I don't think we're ready to see it yet.

And, if you're talking about planet sized mirror arrays being feasible, why not planet sized light blockers arrays that can be modulated? Way easier to construct. Is there a benefit in making the average brightness of a sun look brighter rather than darker?

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