Most fatal US gun incidents occur at home with peoples own guns. Statistics show that gun profilaration correlates with people getting shot. Extreme example: compare western Europe and USA.
Signals capable of transmitting data in GBits/sec range shall be radio in GHz range or even optics. Electricity is an electro-magnetic phenomean and therefore manipulating the magnetic field interferes with the current in the conducter. And as explained many times before; high frequency signals cannot pass through transformers that by nature function as low-pass filters.
When using even higher frequency-signals (even up to optical signals) there would be problems with the variation of the dielectric constants of material surrounding the wires. Some use platic insulators, some paper/oil, some use air, etcetera. These changes would diffuse or reflect signals. And once again it wouldn't pass the transformer.
What do they claim:
They claim they can use the electric utility-network to transmit signals in GBit/sec range over thousands of miles. (OK, this could be done by using the network as antenna and sending very powerfull radio-signals of several kW. Only one transmittor per continent: not very useful).
They claim to use the magnetic field, not the conductor. First ask yourself: what would happen when we have no current? No signal? (this happens 50 times per second, in USA 60 times). Why they claim this: because it is different and can even confuse the average EE that think in currents instead of magnetic fields.
They claim to have patents. Well, I'm not impressed. In USA even perpetual mobiles can be patented (see www.entropysystems.com).
They claim they will demonstrate their system somewhere in 2000 by sending HDTV-signals over thousands of miles of electricity-network. This will be done to find enough investors to make the 300 million dollars they need 'to speed up the development'.
It's their best product (don't like the mediaplayer). Extremely easy to use and it automatically grabs the CD-information like artists and song-titles from internet.
We have a small office using NT SBServer SP4 and 20 NT clients SP4. We have no professional system-operator.
Status after few month: BSOD on NT clients while using Word97 with a large documents. BSOD on NT clients using Paint Shop Pro. 100% chance for BSOD on NT clients sending a print task to the v1.0 HP4500 Color printer driver (don't try this at home). Reinstalled several NT clients after unrecoverable system-hangups while booting up in the morning. Rebooting the NT SBServer at least every 3 weeks (sometimes in the lunch-break) when it starts to have problems with file-serving and Exchange (cleaning the mess). Once the server just forgot all dial-up networking settings (used by Proxy- and Exchange-server).
I suspect the only reason that the server isn't have more problems is that it runs no user-apps.
We use a Compaq PII350 server with brand PII350 clients in original shape.
Computer clock-frequency is around 400 MHz. The resulting RF-frequencies depent on the steepness of the ramp of the signals. At a processor-speed of 400 MHz the RF distortion will reach at least upto 3 GHz. Gaps should be smaller than few cm.
The plates that construct the cage must have good inter-connection on the egdes, closing the box. (otherwise the plates could become antennas!)
For professional EMC protection (not protecting the environment for computer RF, but protecting the computer against high-voltage discharges or lightning) the complete machine should be encapsulated inside a metal cage (preferably copper) with only one hole on one side. All cables should enter through that hole and must be filtered at the entrance. All common-mode wires (ground/shield) should be perfectly connected to the cage at that entrance-point.
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It's called a plant
it does photosynthesis, invented some 1.000.000.000 years ago
Number dislectic?
Most fatal US gun incidents occur at home with peoples own guns. Statistics show that gun profilaration correlates with people getting shot. Extreme example: compare western Europe and USA.
Sorry, wrong subject.
Or maybe even the source ...
Signals capable of transmitting data in GBits/sec range shall be radio in GHz range or even optics. Electricity is an electro-magnetic phenomean and therefore manipulating the magnetic field interferes with the current in the conducter. And as explained many times before; high frequency signals cannot pass through transformers that by nature function as low-pass filters.
When using even higher frequency-signals (even up to optical signals) there would be problems with the variation of the dielectric constants of material surrounding the wires. Some use platic insulators, some paper/oil, some use air, etcetera. These changes would diffuse or reflect signals. And once again it wouldn't pass the transformer.
What do they claim:
They claim they can use the electric utility-network to transmit signals in GBit/sec range over thousands of miles. (OK, this could be done by using the network as antenna and sending very powerfull radio-signals of several kW. Only one transmittor per continent: not very useful).
They claim to use the magnetic field, not the conductor. First ask yourself: what would happen when we have no current? No signal? (this happens 50 times per second, in USA 60 times). Why they claim this: because it is different and can even confuse the average EE that think in currents instead of magnetic fields.
They claim to have patents. Well, I'm not impressed. In USA even perpetual mobiles can be patented (see www.entropysystems.com).
They claim they will demonstrate their system somewhere in 2000 by sending HDTV-signals over thousands of miles of electricity-network. This will be done to find enough investors to make the 300 million dollars they need 'to speed up the development'.
Now I understand, poor investors.
Genius hack that changed the result of the war between the Greek and the Trojans.
In fact there a numerous battles and wars won because of some unexpected hack. Some made history.
It's their best product (don't like the mediaplayer). Extremely easy to use and it automatically grabs the CD-information like artists and song-titles from internet.
We have a small office using NT SBServer SP4 and 20 NT clients SP4. We have no professional system-operator.
Status after few month:
BSOD on NT clients while using Word97 with a large documents.
BSOD on NT clients using Paint Shop Pro.
100% chance for BSOD on NT clients sending a print task to the v1.0 HP4500 Color printer driver (don't try this at home).
Reinstalled several NT clients after unrecoverable system-hangups while booting up in the morning.
Rebooting the NT SBServer at least every 3 weeks (sometimes in the lunch-break) when it starts to have problems with file-serving and Exchange (cleaning the mess).
Once the server just forgot all dial-up networking settings (used by Proxy- and Exchange-server).
I suspect the only reason that the server isn't have more problems is that it runs no user-apps.
We use a Compaq PII350 server with brand PII350 clients in original shape.
Computer clock-frequency is around 400 MHz. The resulting RF-frequencies depent on the steepness of the ramp of the signals. At a processor-speed of 400 MHz the RF distortion will reach at least upto 3 GHz. Gaps should be smaller than few cm.
The plates that construct the cage must have good inter-connection on the egdes, closing the box. (otherwise the plates could become antennas!)
For professional EMC protection (not protecting the environment for computer RF, but protecting the computer against high-voltage discharges or lightning) the complete machine should be encapsulated inside a metal cage (preferably copper) with only one hole on one side. All cables should enter through that hole and must be filtered at the entrance. All common-mode wires (ground/shield) should be perfectly connected to the cage at that entrance-point.