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Comment Not that simple (Score 1) 274

You are making a LOT of assumptions. All of these matter: Ability of the mirror to dissipate energy prior to ablation or meaningful distortion. Collimation of the beam. Reflectivity of the mirror at the laser frequency. Ability of the laser to stay on target, and for how long. Distance from the laser. Atmospheric clarity and particulate density. Atmospheric turbulence. Disruption from atmospheric heating.

It's just not as simple as you paint it.

Comment Re:how much it took (Score 1) 274

CIWS targeting is, as the acronym hints, "close in." You should think of the distance between the shooter (of anything) and the target as a lever. A tiny pivot at one end of the lever (the weapon's aim) translates to a "much" larger motion at the end of the lever (the point of impact.) Tolerances that will work at 100 yards aren't anywhere near close enough to work at many miles, or hundreds of miles in the case of missiles not aimed particularly at you (so you can be sure they will get close enough to hit.)

Comment Suitable defensive grid? (Score 1) 274

There are other issues. That truck was relatively close, between 1 and 2 miles ("more than a mile away"). To hit an ICBM at apogee, even it it goes right over you, you are going to have to spend a lot of energy on atmospheric heating, and you'll lose even more to atmospheric distortion. We're talking 300 to 700 times the distance, depending on exactly what "more than a mile away" actually means. But it is certain that 30 kw at the source will not equate to 30 kw at the target at those distances. So now the problem becomes more than "hit the target", it is also "stay on target for X time", and that assumes that enough energy can be delivered to overcome the missile skin's ability to dissipate it. Because if you can't do all those things, you can't hurt the missile.

Also, the odds of it going right over you kind of suck.

Comment Re: how much it took (Score 2) 274

I"m pretty sure a regular mirror would not be employed.

But here's some hand-wavy math.

If a mirror reflects 99% of the light that hits it at the laser frequency (remember, there's only one frequency to be covered), and the light that hits it can heat proportional to 30 kw (however one figures that), then the mirror is absorbing a 300 watt equivalent and reflecting the rest unless the reflective surface fails.

If the reflective surface is highly heat conductive and the beam isn't all that tightly collimated, likely it won't flinch at all. Like any impact, the effect is all about how much energy you can shoehorn into the smallest possible area. If the beam is ~1/3 of an inch on target, then given 99% reflectivity, it's effectively 1 kw / square inch. If the beam is 1/30th of a square inch on target, it's 30 kw/square inch absorption after reflection. So it makes quite a difference. I think.

Anyone who works with lasers and mirrors, feel free to step in and correct or expand.

Comment ...with remaining eye (Score 1) 274

1) is if the laser is in visible light or not. If you can't see the red dot source a mile off, you can't evade it.

Pretty sure if you "see the red dot a mile off", the location where your eye was is just the steaming, goo-surrounded beginning of a well-cauterized hole that completely transits your head. Assuming tight collimation. With a broader 30 kw beam, your head would explode (steam pressure), and with a really broad beam, you'd turn into a human crisp before you had time to think "Hey! Las..."

Comment Re: Many are leaving ham radio too (Score 1) 135

You have the Part 15 and ISM services for that. You really can buy a microwave link that's metropolitan-distance and legal to use.

We lost much of our 440 capability to PAVE PAWS in California. Remember, Amateur Radio is not the primary service on many bands. The military is on 440.

Comment Re:Many are leaving ham radio too (Score 1) 135

If you want that nearly infinite microwave spectrum, you have the Part 15 and ISM services. Absolutely nothing is stopping you. Power is not the issue with those frequencies, it's line of sight and Fresnel zones.

No, I absolutely do not have to prefix my words with anything. You do that by posting as an anonymous coward. I use my real name to indicate that I stand behind my words.

Submission + - OCO2's 1st map of CO2 output (livescience.com)

WindBourne writes:

This past summer, NASA launched its first satellite devoted to measuring atmospheric carbon dioxide, a heat-trapping gas that is driving global warming.

.... scientists with the space agency unveiled the first carbon maps obtained by the spacecraft, named the Orbiting Carbon Observatory-2, or OCO-2.

This map is little bit more than a month's worth of data.
Note that the large CO2 emissions in the southern hemisphere is due to Ag with a temporary burns, while the emissions in the north are basically at its lowest points. Also note the CO2 to the east of China over the Pacific.

Comment Oh Come On, it's a Press Release (Score 4, Insightful) 88

OK, no real technical data and some absurd claims here.

First all-digital transceiver? No. There have been others. Especially if you allow them to have a DAC and an ADC and no other components in the analog domain, but even without that, there are lots of IoT-class radios with direct-to-digital detectors and digital outputs directly to the antenna. You might have one in your car remote (mine is two-way).

And they have to use patented algorithms? Everybody else can get along with well-known technology old enough that any applicable patents are long expired.

It would be nicer if there was some information about what they are actually doing. If they really have patented it, there's no reason to hold back.

Comment 26% seems a bit high (Score 2) 54

Considering all the different spammers out there, it's hard to imagine any single entity getting 26% of all complaints. Somebody must have been really out to get them, or there must not have been that many complaints submitted. From the quick glance I did, I couldn't determine how many complaints they got, or how many emails this company sent out. They probably would have not gotten such a big fine if their unsubscribe links worked.

I'm from Canada, and as much as I don't like spam, I think that this goes a bit too far. Spam filters are so good now that I rarely see spam in my inbox, and anything that isn't caught can easily be blocked by a filter. This may stop a few companies within the country from sending out emails, but the vast majority of spam comes from outside the country, and this law can't protect against that. It really makes it difficult for small companies to verify that they comply with the regulations. When even companies like Microsoft stop sending out important emails, because there's no way to verity that they have consent for the emails they are sending out, then there's not much the small companies can do to cover themselves if somebody was to complain.

Comment Re:Bad French, man (Score 1) 340

I just checked around the Internet, and I couldn't find a single example of this maple leaf apostrophe in the Tim Hortons logo. Every example I saw had no apostrophe, no maple leaf, just plain old Tim Hortons. I'm not sure where you got your information from, but I've never seen this Tim Hortons sign you're referring to.

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