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The NoCat Wireless Access Point/Night Light
cascadefx writes "O'Reilly's Hacks page has a really great article about a wireless access point that was on display at the recent Emerging Technology Conference. The folks at NoCat.net rigged up a Siemens Speedstream series access point with a low power ultraviolet light to create a wireless lightbulb. Just screw it in place and combine powerline ethernet with a wireless network... and a light, to create a wireless lightbulb. Ubiquitous networking, here we come."
How many times do I have to tell you, turn off the network when you leave the room!
Neck_of_the_Woods
#/usr/local/surf/glassy/overhead
"...a low power ultraviolet light..."
Now maybe us pasty-white geeks can get a decent tan!
GeekNights!
Late Night Radio for Geeks!
... but over here, we just call it a flashlight.
This might seem obvious, but since the network would only work when the lights are on, this would be something of a problem for a very large number of applications where this might actually be of use; for instance, in outdoor spaces where the lights are off during daylight hours.
A workaround, I suppose would be to have a relay in the unit capable of switching the light on and off via network control, X10, or similar while the actual circut remains operational. That would be a likely needed feature on any commercial unit.
~GoRK
Ricochet nodes are very similar, except that they plug into street light photocell connectors.
It's an accesspoint that's hardwired into a lamp base alongside a fluorescent (not UV) lamp bulb.
Receives electricity plus ethernet data from the existing lighting circuit.
Nothing new here... carry on.
Everybody who thinks that powerlines are a great way to run ethernet through your house forget that all of the wire is unshielded thereby creating a large antenna. This typically results in static noise on frequencies up to 80Mhz. I also wonder how hard it would be to just listen to the
3 /isplc2003a 7-4.pdf
network and attach to it. I am still amazed that
the FCC lets any of this trash through. If you
are not convinced go here:
http://www.arrl.org/tis/info/HTML/plc/
And no this does not just affect amateur radio.
Ever thought about radio astronomy
http://www.qsl.net/jh5esm/PLC/isplc200
I don't think powerline will take off. Here's why.
1)Price. I can get a wireless network of comperable or better speed cheaper. The powerline adapters are $80 and only do 14Mbps.
2)Late to market. Although they were promissed for years they just recently got good speeds (>1Mbps). I own an older home, I was considering this tech as an alternative to pulling wire( a huge pain in my house). But, 802.11b got to a resonable price to performance ratio first.
The only advantage I see to powerline is covering long distances in large buildings with no existing networking cabling. Does anyone else see a reason this tech would take off?
Imagine when you tell your girlfriend that you want to leave the lights on when you get down to business - she'll think it's kinky and you get to leave the webcam connected!
Have you seen my stapler?
would be to design a 802.11 repeater. A Accesspoint that simply relay's all traffic it recieves to the other accesspoint and the same in reverse.. this would make setting the whole thing up easier. 1 accesspoint and then 4 repeaters spread out around the first makes a nice coverage map for a large area.
Do not look at laser with remaining good eye.
You should check out Tesla's work. He was broadcasting electricity ages ago. You can build the same getup at home for a few hundred bucks and chemo treatments from the cancer which will most likely ensue.
I saw a news story in Time or Newsweek back in 93 or 94 that showed a guy standing beneath some high voltage lines holding a lightbulb. The bulb was glowing. It was a story on the perceived harms that allegedly resulted from EMFs near high-voltage lines.
A girlfriend of mine (an engineer) from college subsequently did an interesting project in combination with a science writing/journalism class that looked at the public's perception of dangers resulting from EMFs (aside from the obvious) compared to the actual risks disclosed in the medical literature of the time. The disparity between the proven risks and the perceived risks among those surveyed (even those from an engineering college of a major university) was stunning.
In any case, I often wondered if the photo from Time or Newsweek was faked. Even today, I still can't get the idea through my head that significant exposure to EMFs can be anything but bad for you. I'm pretty sure it isn't good for you, but I can't really say why I think that other than ignorant fear of something so powerful.
FWIW, it seems that broadcasting electric would be incredibly wasteful under almost all circumstances, though. Besides, anytime I see references to Tesla, I start to think that black helicopters and aliens can't be far behind. Not a fair bias, perhaps, but it is nevertheless one from which I suffer.
Lots of petrified grits
I just read the article quickly- there's absolutely nothing about a UV light.
That is a regular FL bulb, and though the slashdot story seems to suggest/imply it, the light itself is not being used in any way/shape/form for data transmission/reception. This is simply "toss a small AP inside a tupperware bowl and add a FL light." Wow, what brilliance(pardon the pun.)
I see this as solving a problem that doesn't exist- it takes an electrician all of 15 minutes to add a plug off an existing junction box if you want the AP up high by your lights, and with 802.11g, you can cover an entire cafe from practically any wall socket in the place.
Continuing with the "truly a stupid idea" bit, FL tube bulbs like that get VERY hot(almost as hot as a regular bulb). Cooping one up in a tupperware bowl is a damn fine way to start a fire, or at least kill both components- probably the AP first; if it's electronics don't give out, the transformer's thermal fuse will(that's if it has one- many cheap transformers don't, and will happily melt down, short when the insultation melts, and start a fire.) The UL would die laughing at anyone who even tried to submit it for testing...
Please help metamoderate.
X10 is also extremely slow. Without data compression you can max out at less than 8 bytes per second;
X10 transmits only during the zero crossing of the AC powerline. If memory serves its a 10kHz signal for 1mS. One bit every 1/60th of a second, less framing and retransmissions (X10 includes some redundancy to reduce errors). Effective data rate even with compression would probably be less than 4 bytes per second.
I live very close to the really big, high tension power lines. I don't fear them at all, but someone told me one day about holding a flourescent light up under them at night and watch it light up. I thought, yeah right! So one night, I went out with a big long tube light, and sure as hell, it lit up. It was so blowing my mind. It doesn't light up really bright, but it lights up none the less. I haven't tried it with an incandescent bulb, but I don't think they are supposed to work.
Everybody who thinks that powerlines are a great way to run ethernet through your house forget that all of the wire is unshielded thereby creating a large antenna. This typically results in static noise on frequencies up to 80Mhz.
And that's NOTHING compared to the noise generated on the wiring by connected non-communication appliances.
- Motors. (Especially brush-type, such as vacuum cleaners or hair driers.)
- Switching-type light dimmers.
- Arc lights (fluorescent, "neon" gas discharge tubes, vapor-capsule, etc.)
- Welders.
- Switching-regulators in electronic appliances.
- DIODES in power supplies.
- ANY load turning on or off.
Heck: Even an incandescent bulb produces broad-spectrum audio-through-radio interference on the line - though nothing like what a defective bulb produces as it flickers. (And an old carbon-filiment lamp in a closet has been known to knock out radio reception for much of a city block.)
Be prepared for a LOT of packet corruption - meaning a lot of packet loss plus enough that get past all the redundancy checks to corrupt the actual traffic - if you ever attempt to use a power line for network traffic.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
There's going to be heat pollution either way, but I have a feeling there'd be less with a mirror. Plus, the collector device on Earth could be upgraded as technologies improve.
"I assumed blithely that there were no elves out there in the darkness"
More importantly...
How many geeks does it take to screw up a network?
Watch out - you might get sued for stealing power.
Some people run lots of wire in their backyards and induce a current from the high tension wire's field to provide 'supplemental' power to their houses.
The power company says it's stealing, on the basis that they're only creating a magnetic field, not providing you with current, so when you harvest the current, you're creating a loss for them.
While that may be true, some point out that they're allowed to induce a current in you, your kids, and your dog but you're not allowed to induce a current in anything you own, a seemingly skewed state of affairs.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)