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Comment: Re:A faraday cage has to be grounded to earth. (Score 2) 202

by Matt_Bennett (#46538813) Attached to: Earth Barely Dodged Solar Blast In 2012

Oh my, AC has absolutely no idea about how electricity works.

Electricity always flows in a loop, every time, without exception, period. No loop, no current. No current, no energy. Sometimes the loop includes the capacitance of one disconnected piece of metal next to another, but that also limits the current, and therefore, energy. Sometimes the insulation breaks down, or the field is strong enough to cause an arc to jump the gap.

If welding on your vehicle caused a problem it is because you put the ground clamp in the wrong place, and current passed through something it shouldn't have, which could be because something you thought was a good ground wasn't. Battery connected or disconnected makes no difference.

Comment: Re:ZOMG a bad thing didn't happen! (Score 1) 202

by Matt_Bennett (#46538233) Attached to: Earth Barely Dodged Solar Blast In 2012

Yes, we can actually physically disconnect the transformers- that's what circuit breakers do- and pretty much, they're automated- given the warnings that the satellites give, I suspect that a Carrington event sized CME, at least for modern systems (like in the US) won't be a surprise and can be accommodated- maybe taking significant time to switch everything back on, but without major damage to the infrastructure.

Comment: Re:am i the only one (Score 1) 914

No, you're not the only one. As a punishment, this is simply torture, but I wonder how the mind really acts under this type of drug- how much more the great thinkers (think Einstein and his thought experiments) could have done. It would take a special kind of mind to actually take advantage of this, though.

Comment: Return to very old models? (Score 3, Interesting) 279

by Matt_Bennett (#46497767) Attached to: The Billionaires Privatizing American Science

This seems to be a return to some very old models of research- think Aristotle, Leonardo Da Vinci, where research was not government supported, but either the hobby of the very rich, or the very rich paying someone. I suppose that it could be considered as government supported, as the very rich *were* the government. The institutional government supporting research appears to be a 19th or 20th century change, and that is dominated by military motives.

The super rich have more money than they could possibly spend- why not let them spend that money in the way that they want? Be it driven by guilt or by the desire to make more money... I'd much rather them spend the money on science as opposed to spending their money on becoming part of the government (think Mitt Romney and Michael Bloomberg in the US and Silvio Berlusconi in Italy).

Comment: Re:Not the only state with this law (Score 0) 670

by Matt_Bennett (#45522457) Attached to: Driver Arrested In Ohio For Secret Car Compartment Full of Nothing

A hidden compartment in the car, is, essentially, security through obscurity. If someone knew enough that the supervisor had the receipts, they probably know enough to tear the car apart looking for the safe. What you get with the Brinks truck (or the big vault door at the bank) is a big showy way of saying that what I have is protected- which would draw in the folks that don't really know what they are looking for- think "Indiana Jones and the Last Crusade"

Comment: The most important thing is experience! (Score 2) 215

by Matt_Bennett (#45478757) Attached to: Ask Slashdot: What's On Your Hardware Lab Bench?

I think the primary thing being left out of all the lists is the knowledge gained by experience. If you don't have it, nothing will replace just doing it yourself. Good tools are nice- but face it- EVERY SINGLE PIECE OF TEST EQUIPMENT LIES. Or maybe just doesn't tell you everything. Experience helps in figuring out what really matters. A 100 MHz analog scope is nice, but useless when it comes to a parasitic 1GHz oscillation. A logic analyzer is great, but misses a lot if two outputs are in contention.

The tools I use depend on the job I'm doing. Debugging serial comms? I love my Saleae. Looking at a fast edge? DSA602A.

That said, here's some of my vital lab equipment:

Saleae Logic

Tektronix DSA602A

Temperature controlled soldering Iron

Stereo Microscope

Credit Card


Comment: Re:Fast charge detection (Score 1) 208

by Matt_Bennett (#44862103) Attached to: USB "Condom" Allows You To Practice Safe Charging

Very few computers actually have a switch to cut off current and can actively say 'no' - it is usually done with a thermal fuse- too much current, the fuse gets hot, goes up in resistance, limits the current to the device. The thermal fuses aren't meant to trigger as a matter of course- trigger it too often, and you have to replace it. For most people, that means replacing the motherboard.

Comment: Re:Fast charge detection (Score 1) 208

by Matt_Bennett (#44862071) Attached to: USB "Condom" Allows You To Practice Safe Charging

Why do these solutions need to be soo complex?

Consistency? Not needing to have a specific cable for a specific phone? The USB spec with respect to charging is not incredibly complex, but it is there to give some consistency and assurance you're not going to destroy your device or computer, and still be able to charge at the maximum rate available.

On a computer connected device, the client being well behaved is important- if every port draws the maximum available (before the on-board fuse triggers), there won't be enough current to go around, and can cause functionality on the computer itself.

You are in a maze of little twisting passages, all different.