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Comment The helium will leak out, and drives will fai(#)&a (Score 5, Informative) 175

Worked for an measurement instrument company building instruments that had to work in helium atmosphere. We tried for a long time to seal the helium out. Even to the point of filling the entire inside with glass filled epoxy to prevent intrusions of helium. In the end we gave up, and did a redesign to work in helium. solid metal seals will work, but pretty much any other seal will not.

Comment Raspberry guys incompetent as hardware designers (Score 1) 243

I hate to be swearing in church. Raspberry guys incompetent as hardware designers. They fumbled for almost a decade with nothing, and then found a complete system on a chip from Broadcom. All they had to do was to make a breakout board. They committed errors no professional HW designers would do.
- They did not know they needed magnetics in the ethernet interface, so the first run did not work.
- Picked a very poor chip for power supply that wasted a lot of power for no apparent reason .. and that is pretty much all the design that was done. The rest was mostly pinouts.

On the other hand,
My hat off for incredible handling of marketing, community interaction and many successes.

Comment Re:SDR Hardware (Score 2) 42

Or you can stabilize the temperature of the crystal yourself. We used to build crystal ovens to stabilize crystal oscillators at a constant temperature, and heat it up to 40C (or 50C depending on where you live) with some resistors. Use a thermistor and a regulator to control the temp.

Even without the oven, the R820 dongles on ebay from china gives you good stability after 10 minutes. You can listen to FM radio, Aircraft radio, old cellphones. I have one set up to receive aircraft tracking info as well as one for ship AIS. This gives me a nice map with view of all crafts in the area, with name, destination speed etc.

Comment Re:Why not Mach 22 (Score 1) 221

Nope, you're dead wrong on all points. Flight is far more efficient than a ballistic trajectory. Being in an atmosphere is actually really great because wings allow you to lift far more weight than your engines themselves are capable of. And there's no way to 'glide' in space.

Maybe you lack some understanding here. Take the international space station. It is using almost no fuel as it moves along at Mach 22. If you lower it into the atmosphere, and add wings to it, you will use a lot more fuel to keep it flying.

Comment Why not Mach 22 (Score 4, Interesting) 221

Why not Mach 22

If you first want to go fast, why not just use an intercontinental ballistic missile? It is really simple construction (read fuel tank with orifice), uses cheap fuel, and really need no fancy aerodynamics or control system. Just aim and fire.

The whole idea of pushing a vessel through air for hours and hours, wasting fuel, when it can glide with no friction a few miles higher seems dumb. It also consumes more fuel in total.

Comment Re:10 Mbits isn't enough (Score 3, Informative) 280

If you have 50Mbs you will not have any problems with decent video while playing a game. If you do, the problems must be somewhere else. Your hardware or network congestion/configuration, or many of you family members is watching porn in 4k 3D without your knowledge.

Netflix bitrate for 4k video is 15.6Mbps. Games are mostly under 0.5Mbps. If you run a game server, you may need more than 0.5Mbps.

Comment Account should not try to "get knowledgeable" (Score 5, Insightful) 87

Account should not try to "get knowledgeable" in HTML and JavaScript. He will only seem more of an idiot.
1. Be a great accountant, and dominate your existing field. Teach developers how to make the products more profitable
2. Be a human and a user, and gain user and interface expertise, so you can say what you think about the product with authority and clarity. Tell the developers how to make a more usable product.
3. Can your expertise be used to improve the product? Accounting skills may be important for the platform to make money, and the financial analysis tools needed to understand the web platforms performance.

Comment Absolutely no useful information. (Score 1) 62

No information on bandwidth, signal strength, channel separation or anything else. Only that it "acts like a concert conductor".
How low can a scientific article sink, and still be the basis for a slashdot story? This must be a new low.

Current trans oceanic fibers do transmit multiple colors at high speed with amplifiers on the seabed and no regenerators. New installations carry 64 Tb/s per fiber. and often 64 fibers are laid. Some are left dark, but theoretical capacity for a cable is therefore 8192 TB/s bidirectional capacity

This might be up to 8 billion HD channels or everyone the entire earth watching different TV channels at the same time. Not sure how much more bandwidth is needed in a cable.

Comment Habitat trumph science: Arab backyard Mars-like (Score 1) 190

What arabs lack in sceitific strength, they have in life experience. Mars is a dry desert, and nobody knows dry desert better than arabs. NASA has to travel far, and no NASA engineer has any experience with climate similar to Mars.
Arabs just need to exit their door, and it is like being on Mars. Huge advantage over both USA as well as Europe, Russia and China.

What is the most complex item you can buy in your local store manufactures in an arab country?

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