The potato contains phosphoric acid. This acid causes chemical reactions to occur at each of the electrodes (galvanized nail and copper penny). The reaction at the copper electrode strips electrons from the copper and attaches them to the Hydrogen ions (2H+) in the phosphoric acid. This depletes the electrons on the copper electrode which makes it "hungry" for more. The process creates Hydrogen gas.
Ok, well, maybe you would really really big potato battery, or a really really tiny car...
What's wrong with Yagis?
on
1KM 802.11b @ 2MB
·
· Score: 2, Insightful
Points: 1. Don't use linksys, esp. for backhaul 2. Don't use yagis, horrable FBR (mabey 4:1, if your lucky)
But that's the beauty of Yagis. Front to back ratio. You get signal rejection from the back side of the antenna, that you don't want to hear anyway.
Now you have problems with this distance. Line of sight, for one.
The common calculation calls for a cone shaped space from each antenna meeting at the middle. This is called the Fresnel Zone The calculator says that this zone, for 76km is 28.2 meters (92 feet). So, you have to have 92 feet of clearance. No trees. No buildings. Nothing.
At this distance (44.5 miles) The earth curvature is 90 feet, somehow your signal must peak over that!
So, you are going to need antenna heights of over 150 meters to set up a 802.11b wireless like of this long.
Most engineers say this is simply not feasable. Other issues, such as antenna alighment, water (nasty multipath bounce), WiFi hotspot interferance, and the actual time it takes for a signal to travel that far are issues as well.
So just remember line of sight. If you have clean line of sight to the other endpoint, and clarity through the Fresenel Zone, you might just have a chance for point-point 802.11b wireless.
Do what MMNET, Middle Michigan Network. They got a bunch of the area school districts to band together to build a fiber network. It contains about 300 miles of fiber.
The project worked so well, that they picked up the call to offer the region internet connectivity, through edzone.
It is politically and financially difficult to do, of course. But, Publicly Owned Networks are a good thing... right?
Compare it to cable and satellite TV. Isn't this the same model? Pay for options. Eventually the equipment will go dirt cheap. Look at Cable boxes, dishes. Heck - Look at 1 cent cellphones.
The way you guys talk, you must all have rabbit ears on top of the TV, and a cabinet full of video tapes!
This reminds me of a April Fools joke local chicago radio station wxrt played when I lived there. Found it documented at museumofhoaxes, 1992 -
Pay-Per-Hear: WXRT-FM, a Chicago radio station, announced that it would turn into a digital, commercial-free "pay-per-hear" station. Its signal would be scrambled and divided into five different program formats that listeners would have to pay to listen to. The five formats would be "'XRT Basic," "'XRT Live," "'XRT Gold," "'XRT Espanol" and "sports-rock." The station announced the format change all day and then switched to a scrambled signal for several minutes. Hundreds of listeners reportedly called in to protest the change, and one listener even showed up with a picket sign outside the station.
Man, you guys are harsh. Beating up on such a new technology.
I travel a couple hours a day and suffer through the misrable choices of broadcast raido. The popular stations weigh their advertising so heavily into the rush-hour that it's unbearable. Public Radio is great, but listening to NPR's Morning Edition can wear on you after a few weeks. Give me options!
Actually, here in Holland MI, The municipal communications infrastructure was paid for out of the profits of the Municipal power plant. It has nothing to do with taxes.
In fact, the power plant is a money-maker for the city, actually injecting cash back into the local government.
Well, this is something I know a bit about.
Michigan's state economic development group is pushing for this concept pretty heavily, in light of the shortcomings of the regional RBOC. Check it out at:
The LinkMichigan press release
and document here
We, in Holland Michigan (Birthplace of Slashdot!), have been struggling with this for quite a while, as we have a City-owned fiber infrastructure, and a city ordinance that restricts commercial fiber build-outs. The local residents have suffered because the local cable company (now AT&T) has been very slow to provide enhanced cable services (read digital cable and cable Internet access) because of the restrictions. Currently the City cannot actively compete as a CLEC due to municipal law. They are trying to change that.
It's quite a battle here in Michigan with Ameritech. They will do all in their power to protect their Monopoly/Oligopoly. Lots of info available at
Neil Lehto's page
The all-important, all-missing, Last Mile alternatives are what drives Municipalities to enter the communications infrastructure foray. Residents and resident business demand broadband, and can't get it (cost-effectively or at all) from their local communications provider. The advent of Broadband Cable and wireless, however, puts any Municipal infrastructure solution further down on the list for resolving last mile communications problems.
Slashdot Mirror
From http://www.quantumscientific.com/pclock.html
The potato contains phosphoric acid. This acid causes chemical reactions to occur at each of the electrodes (galvanized nail and copper penny). The reaction at the copper electrode strips electrons from the copper and attaches them to the Hydrogen ions (2H+) in the phosphoric acid. This depletes the electrons on the copper electrode which makes it "hungry" for more. The process creates Hydrogen gas.
Ok, well, maybe you would really really big potato battery, or a really really tiny car...
Points:
1. Don't use linksys, esp. for backhaul
2. Don't use yagis, horrable FBR (mabey 4:1, if your lucky)
But that's the beauty of Yagis. Front to back ratio. You get signal rejection from the back side of the antenna, that you don't want to hear anyway.
Sorry, guys. Typo on my part. But I hate nits, so thanks for pickin'.
I stand corrected.
1 milliwatt = 0.001 Watt
100 mw is 1 tenth a watt, not 1 watt.
Sorry. Missed my link. Type too fast:
You can check out the various power limitations for 802.11b across the world at this site:
Maximum Power Levels and Antenna Gains
A country to regulation listing is here
Sorry about that. Us Yankee's often forget to see beyond our own little world.
Since I'm a cisco bigot, let me quote them once again with Cisco's Maximum power listings
Unfortunately, Egypt is not listed there. A lot of the Arab world follows EMEA.
100mw is the maximum across the world. Many countries have lower maximums.
Linksys outputs 50mw. If you were to go to the FCC regulation maximum of 100mw (1 watt), you would do better.
If you use Cisco's Wireless Calculator Excel spreadsheet, you will see that a 21 dbi parabolic dish (as seen here could grant you 76.1 kilometers.
Now you have problems with this distance. Line of sight, for one.
The common calculation calls for a cone shaped space from each antenna meeting at the middle. This is called the Fresnel Zone The calculator says that this zone, for 76km is 28.2 meters (92 feet). So, you have to have 92 feet of clearance. No trees. No buildings. Nothing.
At this distance (44.5 miles) The earth curvature is 90 feet, somehow your signal must peak over that!
So, you are going to need antenna heights of over 150 meters to set up a 802.11b wireless like of this long.
Most engineers say this is simply not feasable. Other issues, such as antenna alighment, water (nasty multipath bounce), WiFi hotspot interferance, and the actual time it takes for a signal to travel that far are issues as well.
So just remember line of sight. If you have clean line of sight to the other endpoint, and clarity through the Fresenel Zone, you might just have a chance for point-point 802.11b wireless.
Cheers!
Ok to follow the theme. Pedaling to the oldies:
Joust would lend itself quite well to the pedal-for-your-life concept.
Now, if somebody would just brew up an easy interface for MAME, we'd be set!
Just don't get it confused with a robomower.
My neighbor has one of these. He glued a GI-Joe to the top of it. Yee haw!
Do what MMNET, Middle Michigan Network. They got a bunch of the area school districts to band together to build a fiber network. It contains about 300 miles of fiber.
The project worked so well, that they picked up the call to offer the region internet connectivity, through edzone.
It is politically and financially difficult to do, of course. But, Publicly Owned Networks are a good thing... right?
Compare it to cable and satellite TV. Isn't this the same model? Pay for options. Eventually the equipment will go dirt cheap. Look at Cable boxes, dishes. Heck - Look at 1 cent cellphones.
The way you guys talk, you must all have rabbit ears on top of the TV, and a cabinet full of video tapes!
This reminds me of a April Fools joke local chicago radio station wxrt played when I lived there. Found it documented at museumofhoaxes, 1992 -
Pay-Per-Hear: WXRT-FM, a Chicago radio station, announced that it would turn into a digital, commercial-free "pay-per-hear" station. Its signal would be scrambled and divided into five different program formats that listeners would have to pay to listen to. The five formats would be "'XRT Basic," "'XRT Live," "'XRT Gold," "'XRT Espanol" and "sports-rock." The station announced the format change all day and then switched to a scrambled signal for several minutes. Hundreds of listeners reportedly called in to protest the change, and one listener even showed up with a picket sign outside the station.
Man, you guys are harsh. Beating up on such a new technology.
I travel a couple hours a day and suffer through the misrable choices of broadcast raido. The popular stations weigh their advertising so heavily into the rush-hour that it's unbearable. Public Radio is great, but listening to NPR's Morning Edition can wear on you after a few weeks. Give me options!
So, I have this nice little H323 IP phone, and a broadband connection....
Are there any public H323 gateways out there? I could point my phone to it and call the world!
The optiPoint 100 advance, for one.
They get much more usefull if they have a SPBX (Soft PBX) or something.
Actually, here in Holland MI, The municipal communications infrastructure was paid for out of the profits of the Municipal power plant. It has nothing to do with taxes.
In fact, the power plant is a money-maker for the city, actually injecting cash back into the local government.
All this, and we have LOW power rates. Woo woo!
We, in Holland Michigan (Birthplace of Slashdot!), have been struggling with this for quite a while, as we have a City-owned fiber infrastructure, and a city ordinance that restricts commercial fiber build-outs. The local residents have suffered because the local cable company (now AT&T) has been very slow to provide enhanced cable services (read digital cable and cable Internet access) because of the restrictions. Currently the City cannot actively compete as a CLEC due to municipal law. They are trying to change that.
It's quite a battle here in Michigan with Ameritech. They will do all in their power to protect their Monopoly/Oligopoly. Lots of info available at Neil Lehto's page
The all-important, all-missing, Last Mile alternatives are what drives Municipalities to enter the communications infrastructure foray. Residents and resident business demand broadband, and can't get it (cost-effectively or at all) from their local communications provider. The advent of Broadband Cable and wireless, however, puts any Municipal infrastructure solution further down on the list for resolving last mile communications problems.
I just got a SMB barricade last week. Supports numerous clients, and wireless network to a cablemodem.
Got it with rebate from CompUSA for 50 bucks or so.
That's a good deal, for a 4 port switch, router, print server...
Oh.. bummer. rebate period is over:
info was here
" A Date Which Will Live in Infamy "
f In famy.ram
Actual audio at:
http://www.soundsofhistory.com/RooseveltFD/DayO