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Comment Re:How does the data get around the transformers? (Score 2) 120

This has been "going to happen" since, at least, the 1940s. At least once a decade someone reinvents the idea and creates a lot of interest. Then it dies again for a while.

The entire power grid is an RF choke. RF over the power lines works until it gets to a transformer. That's a good thing because it reduces impulse noise which can play havoc with electronic equipment. Fast rise time impulse noise on power lines is a problem in electronic equipment and instrumentation.

Comment Re:Nothing to see... (Score 2) 346

That's what the Tempest standard is for. It dates from the late 70s/early 80s when they banned all removable anything.
The guy they busted was an intelligence analyst. That might explain his access. If the information was secret or higher then it shouldn't be available to someone working alone on an office desktop. The entire incident doesn't make much sense.

Everything I've seen from that leak has been been in the media before. No where is the classification level mentioned.

Wall St firms have better security than this. All access to sensitive information is logged, and passed on to security. If the access isn't legitimate then you're out the door at minimum.

Comment Re:A Simple Solution (Score 1) 548

I find this whole argument ridiculous. Isn't the simple, effective solution to simply charge customers based on the amount of data they consume?

Yes, that makes sense. Or you can get a dedicated connection. A T1 (1.5 Mbs) is about $450.00 a month. Or you can get a T3 (43.2 Mbs) for $4,000.00/month or more.

I have a broadband connection that gives me 26.03 Mbs down and 5.23 Mbs up (at 10:00 am). It's a shared resource. The speed varies depending on the total load on the distribtuion node. For the difference in cost it's worth it. Most of the time I get better then T1 speed for one tenth of the cost.

Comment Re:16,800 W? - WTF?! (Score 1) 450

From an article on

The battery capacity is 53 KWH

The charge rate for 4 hours would be 12.25 KW. so the current would be 55 Amps at 240 Volts.

The charge rate for 8 hours would be 6.75 KW so the current would be 27.6 Amps at 240 Volts.

That does not include any inefficiency in the charger.

The motor is 185 KW (248 hp). The article doesn't give the weight.

Comment Re:What kind of direct current source? (Score 1) 603

The power going to your house is AC. Batteries are DC. In order to charge a battery you have to convert AC to DC. You do that with a rectifier normally or an AC motor/DC generator set. The problem with fast charging is the current (Amps) required.

The quantity of energy is KWH (Killo Watt Hours). If the battery stores 30KWH then it would take 30KW (the rate) for 1 hour to charge the battery.

For a discharged 48 Volt battery the charging current for one hour would be;
    I = 30 KW (charging rate) / 48 (charging voltage) = 625 Amps.
If you cut the time to 6 minutes then the current would be 10 times that (6,250 Amps). I wouldn't want to be anywhere near that operation.

The ampacity of wire depends on it's cross sectional area.
A current of 625 Amps is close to the spec for 2000 MCM (depending on temperature rating), which is 1.92 inches (48.8 mm) in diameter, so it would require buss bars. The fast charge rate (6 minutes) would require over 10 times that conductor cross section area.
Conductors that big are not manageable by hand and currents that high are very dangerous.

Comment Re:Rubbish (Score 1) 603

So physics says the if you want to charge a car to go 375 miles and the car has the same drag as a honda then it takes 1.8 megawatts if you want to charge it in 6 minutes. that's the minimum. bad batteries and motors require more.

Your numbers look right. The charging current at 240 Volts would be 7,500 amps.
0000 AGW copper is only good for 380 Amps. It would require buss bars.

Standard service is usually 150 - 200 Amp.

Something got misquoted or it's wishful thinking.

Comment Re:I hope Oracle doesn't get a clue (Score 3, Informative) 388

I hope they pay the price for their ignorance and hubris. What did they get for buying Sun, exactly?

They got hardware which is what they've wanted for a long time. Sun has a wide range of great hardware and a very solid OS. The evolution of Oracle DB requires intimate control of the system at the hardware level. The database server will be able to directly control resource allocation.

I don't think they were interested in the rest of the company. It's probably just in the way.
It appears they are focusing on their area of expertise.

Comment Re:Turbine (Score 2, Insightful) 338

The word, I think, is "turbine" (or even "jet turbine,")-- not "Jet powered".

How noisy were they?

Not noisy at all. One of my customers brought one into the shop so we could check it out. It was quieter then most cars. It just sounded different. The mileage was better then most cars of that time.

I rode in it. It was very quiet inside and had excellent acceleration. A really nice car. It's too bad they never put them in production.

Comment Re:Watt's Up Pro (Score 1) 172

I'd like to monitor the entire house. I've thought about the whole shebang... monitoring every circuit - but that would be more complex and expensive.

Black and Decker has a unit that mounts on the meter head and gets info from the rotating disk.
There is no wiring involved.
The remote unit recieves the signal and displays power usage, etc.
On the web it's around $70.00.

Black and decker

Comment Re:Isn't that just a network? (Score 1) 258

There is no excuse for critical anything to be on the Internet. This is what happens when people are put in charge of something they don't understand.

Inventing an answer for an imaginary problem is not big thing. Implementing it is a different story.

The next big step is to design encryption technology to make Etch-a-Sketch secure.

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