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Comment Re:Passed data with a ton of noise? (Score 1) 351 351

The question is: is the signal-to-noise ratio good enough? If so a cheap cable that passes the data is every bit as good as an expensive one, so long as the packets arrive intact at the other end.

Ethernet already does a lot to counter noise. The signals are differential pairs (so instead of having ground and signal, you have signal+ and signal-). The wire pairs are twisted, which keeps them in close proximity. Interference tends to be common mode noise (so for two wires close together it will affect the signal in each wire almost the same), and differential amplifiers are designed to only amplify the difference between the two wires and will therefore reject common mode noise. Each end also has an isolating transformer, and each end has proper termination (to avoid things like reflections which can bugger up signal integrity). It takes a significantly terrible out-of-spec twisted pair cable to make ethernet stop working.

Incidentally, the signalling for 100baseTX ethernet only has a fundamental frequency of 31.25MHz (naively people would expect 1MHz per 1Mbps but this is not so). 100baseTX uses a 3 level (in other words +1, 0, -1) non return to zero signalling (in other words, a 1 will cause the signal to change level and a 0 will cause the signal to remain at the current level - or it might be the other way around, it's a long time since I did this stuff). Each 4 bits is encoded into a 5 bit symbol designed to prevent long runs of 0s (which would cause the signal level to remain constant for too long). Lots of people call an ethernet connection a "broadband" connection, but it's not, it's baseband (hence the "base" in 100baseTX).


Video Urthecast Brings You Earth Images and Videos from the ISS (Video) 16 16

Most of us probably won't ever visit the International Space Station (ISS) and look down at the Earth (motto: "The only planet we know has beer, so let's not ruin it"). Looking at pictures and videos made by cameras mounted on the ISS is about as close as we're going to get. There's already an ISS HD Earth Viewing Experiment on Ustream, but Urthecast is putting out higher-definition images than what you see on Ustream, and has plans to put out even clearer images and video before long. While Urthecast is likely to accumulate plenty of "oohs" and "aahhs" as it rolls along, according to CEO Scott Larson their real objective is to sell imagery -- and not necessarily just from the visible light band of the overall spectrum -- to industrial and government users. People like us are still invited to look at (and marvel at) lovely images of our planetary home.

NOTE: Today's video is about 4:30 long. If you want to watch and listen to more of Mr. Larson, we have a second "bonus" (Flash) video for you. Or you can read the transcript, which covers both videos.

Comment Re:Please (Score 1) 354 354

Its like saying "Hey, Chevrolet, you know your customers like the radio station set to 101.9, why cant you engineer your cars to respect their choice instead of forcing your nefarious 101.5 agenda."

Yeah, but this is a Mozilla car analogy we're talking about here.

In the current 2015.7 model, release, the UX team has decided that a 5-button hamburger menu on an AM dial (and only from 1100Khz to 1150KHz in 10KHz increments) is all that's needed. Users who want to access a wider range of frequencies in the AM band are free to write an extension or purchase a third-party radio head unit.

To further improve the user experience, we remind prospective extension developers that in the Aurora channel for the 2016.1 model year, the about:config setting for frequency.megavskilohertz has been removed, along with the FM antenna. The UX team has made this recommendation based on telemetry that suggests that few drivers actually listen to FM radio, especially since the 2013.6 model, in which the AM/FM toggle switch was removed because the UX team for 2012.1 felt it was cluttering the dashboard.

Comment Re: Looking more and more likely all the time... (Score 1) 508 508

What do you think is more likely.
What is more likely to be right in the end:
a) half a dozen research institutes run by real scientists claiming: there might/is something about the drive
b) a few hundred /. posters who dismiss it as "can't work" based on mediocre (mainly american) physics education

My bet is on the Scientists.

Comment Re: Looking more and more likely all the time... (Score 1) 508 508

This "article" does not claim that a (general) "reaction less drive" automatically is a violation of the law "of conversation of impulse".

It only claims that the drive in question is, which is wrong, as the authors don't grasp that law ;D

Pretty simple speaking: the law of conversation of impulse simply says nothing about reaction less drives. Hence why I'm nitpicking on everyone claiming this bullshit.

The law of conservation of momentum only affects situations/stuff where momentum is exchanged. Basic example is the "boy throwing out rocks at the end of the boat".

It says nothing about a boat getting momentum by "other means" ... plain and simple.

Comment Re: Looking more and more likely all the time... (Score 1) 508 508

Impulse is a mathematical construct. Nothing else.

Imagine two identical cars colliding with exactly the same speed straight ahead.

After the impact they both sit exactly on the same spot damaged with the front crushed and their impulse is ZERO.

Now we wonder how that can be as both cars, depending on speed, had quite a high impulse/momentum before the crash.

However if you understand math you figure that "impulse" is not only m * v but a vector; and on top of that we understand the total impulse (sum of the impuls/momentums) was ZERO already before the crash.

So ... in case of this particular EM drive we only need to figure what the other "thing" is that gains momentum or accept that there are ways to gain momentum that do not violate the "law of conversation of momentum".

(Because that law does not even touch other ways, it only makes clear under which circumstances it considers not to be violated, and the EM drive is IMHO not such a circumstance)

Comment Re:Physics time! (Score 1) 508 508

Oh, that is simple.

I don't insult other people for no reason :D for a start.

And I eat and drink in most pubs (which I frequent, not those, where I'm only once a month, obviously) in my town for free. Actually I guess if I would ask the waitresses would even feed me :D but I guess in public that would be more embarrassing than fun.

How do you feed? I hope you switched your diet away from little children. I can understand they are tasty when freshly roasted and not to old, but keep in mind: humans have very bad eating habits. They are full with heavy metals and other poisons. Most humans (I mean their meat) would not pass the tests in a german butchery.

Comment Re: Looking more and more likely all the time... (Score 1) 508 508

"Forward theory" means:
o Someone has a theory
o Afterwards they try to build a device following that theory

Like with the A-Bomb.

With that drive it is just the same. The inventor published his ideas years ago, and now scientists around the globe try to build a device according to his theories.

The original theory presented has been torn to pieces
Any links to that?

Comment Re: Looking more and more likely all the time... (Score 1) 508 508

Then explain why it does it.
For me it does not.

The law of conservation of momentum is pretty simple.

You have a boat, throw out a stone to the back. The sum of the boats momentum plus the stones momentum before the action and after the action is the same.

Now, why do you believe there is no other way that the boat can gain momentum? The "law" certainly does not even cover this question and this engine ;D

And if you would kindly read up the theories about it you would figure that virtual particles take the "other part" of the momentum ;D So it is even covered by the most basic variant of that law.

However, it would be cool if the english speaking world would follow the rest of the world and would stop calling basic laws like the law of conversation of energy and momentum "laws". They are no laws of physics, they are axioms. Perhaps that would make teaching them in school more easy.

E.g, all "laws of thermodynamics" are in german simply "axioms" and not laws. However there are plenty of proven laws of physics and it is important IMHO to distinguish between laws and axioms.

GNU is Not Unix

Video Purism Offers Free (as in Freedom) Laptops (Video) 75 75

Purism uses its own OS, PureOS, which is a Debian derivative by way of Ubuntu and other members of the Debian-derivative family, but with no taint of proprietary code. Now imagine all the binaries stripped out of the Linux kernel, making it closer to the FSF ideal of a 100% free operating system than the Linux kernel in use almost everywhere else.

They're still using a proprietary BIOS, but have people working on a Free one. The main thing, though, is that Purism is working to give you all the privacy and freedom they can -- with more coming as they keep working to replace proprietary bits of the OS, BIOS, and hardware drivers with Free Software. Best of all, even if you don't need a new laptop right now, you can download PureOS and run it on any compatible hardware you already own.

"When the going gets weird, the weird turn pro..." -- Hunter S. Thompson