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Comment Re:ECC (Score 1) 145

The situation for AMSAT is still pretty bad, as far as I've heard. As a radio amateur group (and one that has launched quite a few satellites as space hitch-hikers) they can't afford the good stuff, but they get some donated by NASA and some of the commercial satellite companies. Only a few years ago they were still using the 1802 as their main vehicle controller, as that was their main choice in silicon-on-sapphire CPUs. They get some donations of space-qualified solar cells. They scrub their memory continuously, They use no boot ROMS. The program is loaded entirely by hardware, and then the CPU is started.

Comment Re:Basic Physics (Score 1) 54

Or, perhaps, your own understanding of physics is bullshit because, well. Physics is bullshit. And this is why physics hasn't accomplished anything significant since the atom bomb. It's mental masturbation.

Well here's some things physicists have done after the bomb that I thought of off the top of my head: Lasers (and laser-related stuff like laser spectroscopy), Magnetic Resonance Imaging, Holograms, atomic clocks, high temperature superconductors, tunnel diode, scanning tunneling electron microscope, atomic force microscope, stochastic resonance, charged coupled devices... All kinds of stuff that maybe isn't as high profile as the atomic bomb, but are essential to things you take for granted, like flash memory and liquid crystal displays in your electronics or the Hall effect sensors in your anti-lock brakes.

In any case, leaving aside the obvious hooey , if physics were mental masturbation then anyone could do it. It's the fact that so few can do it that makes so many people see it as a pointless and trivial exercise.

Comment Re: "Of course it can," says government (Score 1) 145

The comment I was responding to was regarding HAARP. And that's "except" FYI. :-) ECC is actually more reliable, for its problem domain, than a triple voting system. The probability that you would arrive at a valid ECC code for bad data due to multiple bit flips is much lower than than the probability of two out of three systems voting wrong. So, it is at least theoretically possible to design a computer system with data integrity throughout that exceeds that of a voting system.

Comment Re:"Of course it can," says government (Score 1) 145

Faraday cages are really good for RF, and I was writing about HAARP. The X rays that you get from a radiologist don't have the same energy level as cosmic rays. The best we can do about energetic cosmic rays is to make our equipment less susceptible, because you can never have enough shielding.

Comment ECC (Score 5, Insightful) 145

This is why ECC is used to protect memory and data busses. At least on the good stuff :-) . One of the issues is die shrink. As the minimum detail slze of the IC process gets smaller, the potential for radiation to flip a bit gets higher.

Silicon-on-sapphire is the main way to implement silicon-on-insulator, which is more protective of radiation bit flips and less likely to latch-up. But since these have historically been required only for space satellites, they have been horribly expensive. Imagine running an entire IC fabrication just to make a few chips. As there are more applications for rad-hard chips, the price could fall.

Comment Re:Boo hoo, just stop rainwater from leaching lead (Score 4, Informative) 188

You might not think so, because elemental lead is not water-soluble. However compounds of lead like hydroxides or carbonates are soluble and can form from elemental lead by contact with water, e.g., 2Pb + O2 + 2H2O -> 2 Pb(OH)2.

This is why it's perfectly safe to drink wine from leaded crystal wine glasses, but a bad idea to store wine in a leaded crystal decanter.

Comment Re:Ways around this (Score 1) 426

American border patrol was just given authority to conduct is security theatre in Canadian airports too

There is one subtle difference doing it in Canada though and that is while Canadian law requires you to tell the truth you have the option to withdraw from the process at any time and not enter the US. Hence if you are asked for your phone you can choose to decline but then you will not be allowed to travel to the US. This is actually quite a sensible arrangement: countries should be free to set their entrance requirements and foreign travelers should be free to decline to travel there if they do not like them. The problem is that if you come from Europe you are already in the US and declining leads to arrest and detention not just denied entry and a return flight home.

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