Please create an account to participate in the Slashdot moderation system

 


Forgot your password?
Close
typodupeerror
×
The Internet

Submission + - DIY 4G Antenna Design for the Holidays?

Submitted by eldavojohn
eldavojohn writes: This holiday season I will return to the land of my childhood. It is flat and desolate with the nearest major city being a three hour car drive away. Although being able to hear the blood pulse through your ears and enjoying the full milky way is nice, I have finally convinced my parents to get "the internet." It's basically a Verizon Jetpack that receives 4G connected to a router. My mom says it works great but she has complained of it cutting in and out. I know where the tower is, this land is so flat and so devoid of light pollution that the tower and all windmills are supernovas on the horizon at night. Usually I use my rooted Galaxy Nexus to read Slashdot, reply to work e-mails, etc. I would like to build an antenna for her 4G device so they can finally enjoy information the way I have. I have access to tons of scrap copper, wood, steel, etc and could probably hit a scrap yard if something else were needed. As a kid, I would build various quad antennas in an attempt to get better radio and TV reception (is the new digital television antenna design any different?) but I have no experience with building 4G antennas. I assume the sizes and lengths would be much different? After shopping around any 4G antenna costs way too much money. So, Slashdot, do you have any resources, suggestions, books, ideas or otherwise about building something to connect to a Jetpack antenna port? I've got a Masters of Science but it's in Computer Science so if you do explain complicated circuits it helps to explain it like I'm five. I've used baluns before in antenna design but after pulling up unidirectional and reflector antenna designs, I realize I might be in a little over my head. Is there an industry standard book on building antennas for any spectrum?
Power

Submission + - Rice creates graphene/nanotube hybrid that could redefine energy storage (extremetech.com)

Submitted by
MrSeb
MrSeb writes: "What could possibly be cooler than graphene or carbon nanotubes? Rice University’s new material that consists of forests of carbon nanotubes grown on sheets of graphene, of course! This graphene/nanotube hybrid is as awesome as it sounds, too; we’re talking about a material that might be the single best electrode interface possible, potentially revolutionizing both energy storage (batteries, supercapacitors) and electronics. This new material basically consists of a sheet of graphene, with carbon nanotubes up to a length of 120 microns (0.12mm) growing off it, which is really rather impressive at this scale. If we scaled it up to actual trees, they would rise into outer space. Most importantly, though, is that the bonds between the graphene and nanotubes are completely seamless — as far as electrons are concerned, there is absolutely no resistance when transitioning between graphene and nanotube. Why is this important? Because this hybrid material has a ridiculously vast surface area: A single gram of the new material has a surface area of 2,000 square meters (21,500 sq ft) — half an acre of the most conductive material in the world. When it comes to energy storage, there is a direct correlation between energy density and the surface area of the electrodes — this new graphene/nanotube hybrid could result in significantly smaller batteries, or larger batteries that can do more work. In testing, Rice University created a supercapacitor with the new material that matches “the best carbon-based supercapacitors that have ever been made,” which is impressive because “we’re not really a supercapacitor lab, and still we were able to match the performance because of the quality of the electrode.”"

Submission + - NASA: Curiosity has found plastic on Mars (nasaupdatecenter.us) 2

Submitted by dsinc
dsinc writes: Last week Curiosity was able to use its SAM (Sample Analysis at Mars) device to confirm the discovery. A robotic arm with a complex system of Spectral Analysis devices was able to vaporize and identify gasses from the sample, concluding that it is in fact plastic. How plastic formed or ended up on the Martian surface is quite an exciting mystery that sparks many questions. The type of plastic sampled as we know so far can only be formed using petrochemicals, meaning not only that there could possibly be a source of oil on the Red Planet, but that somehow it got turned into plastic. Even more interesting is that oil or petrochemicals used to create this type of plastic are only known to come from ancient fossilized organic materials, such as zooplankton and algae, which geochemical processes convert into oil pointing to the earthshaking evidence that there was once life on mars.

"Right now we have multiple working hypotheses, and each hypothesis makes certain predictions about things like what the spherules are made of and how they are distributed," said Curiosity's principal investigator, Steve Squyres, of Cornell University, Ithaca, N.Y. "Our job as we explore Matijevic Hill in the months ahead will be to make the observations that will let us test all the hypotheses carefully, and find the one that best fits the observations."
Businesses

Submission + - Judge orders tobacco companies to say they lied

Submitted by Freshly Exhumed
Freshly Exhumed writes: U.S. District Judge Gladys Kessler may have recently witnessed Apple's impertinent fudging of a UK court's ordered confession of misdeeds and taken away an important lesson, because she has demanded that U.S. tobacco companies publish confessional ads beginning with very specific wording indicating that they lied to consumers over the health dangers of tobacco. Each corrective ad is to be prefaced by a statement that a federal court has concluded that the defendant tobacco companies "deliberately deceived the American public about the health effects of smoking." Among the required statements are that smoking kills more people than murder, AIDS, suicide, drugs, car crashes and alcohol combined, and that "secondhand smoke kills over 3,000 Americans a year." Perhaps big tobacco will try to fight the order by claiming free speech rights under the First Amendment in line with the Citizens United ruling?

Submission + - Ask Slashdot: Geekiest way to cook a turkey? (altonbrown.com)

Submitted by almostadnsguy
almostadnsguy writes: There seem to be a lot of ways to cook a turkey the geekiest ones are probably out of the realm of possibility for normal geeks. However, Within the limits of normal society (or outside if you wish) what is the geekiest way to do it. The link included is to the web site of my favorite geek celebre-chef (Alton Brown).

Comment Re:0.005$ is not enough (Score 1) 38

by java_dev (#41851583) Attached to: Behind the Scenes At NASA's Mission Control Center

They do so much with so little?

My neighbor has been hired into Goddard as a contractor twice now to get two different programs back on track because they were over budget and behind schedule.

There is A LOT of dead wood at NASA. For example, he took instruments to the JHU Applied Physics Lab for shake and vibe testing because APL could do the testing in a day, while the NASA union guys would take a week for the same job.

Comment Hacking (Score 1) 276

The fascination of the Apple II in 5th grade math lab, getting a PC when they first came out, and the arcane 8" thick code dump print outs my VM programmer father brought home drove me to learn to code. I dont think what drove us exists any more.

An area of fascination that does exist is computer and network security (ie. penetrating and defending syatems). What kid wouldnt be interested in that?

It's the angle I plan to use to get my son interested in coding when he gets a little older.

Comment Best two years of my career (Score 3, Interesting) 309

by java_dev (#38034514) Attached to: A Job Fair For Jobs In India — In California

I lved in India with my family setting up some engineering teams. Best two years of my career... but also the most challenging, simply because you have no idea how hard it is to adjust to living in a foreign culture until you have to do it.

Of course, if you have a crappy boss, it'll completely suck - like anywhere else..
Cellphones

Submission + - Lawsuit: Windows Phone 7 Spies On Users (itworld.com)

Submitted by
jfruhlinger
jfruhlinger writes: "Microsoft wants to emulate the success of the iPhone, but they probably didn't want to follow in Apple's footsteps this way: a class action lawsuit claims that Windows Phone 7 is collecting location data on users, even when they request that it stop. But a look at the internals shows that Microsoft might not be acting as Big Brother-ish as it appears."

Slashdot Top Deals

FORTRAN is not a flower but a weed -- it is hardy, occasionally blooms, and grows in every computer. -- A.J. Perlis

Close