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This is just a random press release from a company selling boring old wireless kit. There isn't anything special about getting 5km of range with off the shelf wireless gear,

If anyone cares the math is not that hard to follow:

You take the transmitter output power, subtract any loss in the cable between the transmitter and the antenna, add the gain of the anteana. http://db.osoal.org.nz/eirp-calculator.html

Then you have to subtract the free space loss of your path ( the loss you get by putting the signal across the air ): http://db.osoal.org.nz/freespace-loss-calculator.h tml

And finally you add the recieve gain of the receiving antenna, subtract the loss from the cable on the recieving end and compare with the receive sensitivity of your wireless receiver. I have bundled the rest of the calculation into this bit of javascript.

For example, if I have two 2.4ghz radios that output 15dbm (32mw) that have a recieve sensitivity of -83db that are in waterproof boxes on the antenna mounting connected to two 22db antenna's 5km apart very roughly.

15db - 1db + 22db = 36db or ~3981mw (just under the 4 watt max).

- 121.65db for our free space loss

+ 22db - 1db = -64.65

-64.65 is the strength of the signal received at the other end, fortunately the receiver has a receive sensitivity of -83 so we are in business. There is a link margin of ~19db to account for a little bit of noise, fade, solar flares, alien abductions etc.

If you want more range, increase the power of the transmitter or the gain of your antenna. The government limits ( 4 watts for 2.4ghz, 250mw for 5.3ghz and 4 watts for 5.8Ghz in New Zealand ) are going to determine your maximum range barring some magical new wireless gear that has a better receive sensitivity.

This is just a random press release from a company selling boring old wireless kit. There isn't anything special about getting 5km of range with off the shelf wireless gear,

If anyone cares the math is not that hard to follow:

You take the transmitter output power, subtract any loss in the cable between the transmitter and the antenna, add the gain of the anteana. http://db.osoal.org.nz/eirp-calculator.html

Then you have to subtract the free space loss of your path ( the loss you get by putting the signal across the air ): http://db.osoal.org.nz/freespace-loss-calculator.h tml

And finally you add the recieve gain of the receiving antenna, subtract the loss from the cable on the recieving end and compare with the receive sensitivity of your wireless receiver. I have bundled the rest of the calculation into this bit of javascript.

For example, if I have two 2.4ghz radios that output 15dbm (32mw) that have a recieve sensitivity of -83db that are in waterproof boxes on the antenna mounting connected to two 22db antenna's 5km apart very roughly.

15db - 1db + 22db = 36db or ~3981mw (just under the 4 watt max).

- 121.65db for our free space loss

+ 22db - 1db = -64.65

-64.65 is the strength of the signal received at the other end, fortunately the receiver has a receive sensitivity of -83 so we are in business. There is a link margin of ~19db to account for a little bit of noise, fade, solar flares, alien abductions etc.

If you want more range, increase the power of the transmitter or the gain of your antenna. The government limits ( 4 watts for 2.4ghz, 250mw for 5.3ghz and 4 watts for 5.8Ghz in New Zealand ) are going to determine your maximum range barring some magical new wireless gear that has a better receive sensitivity.

This is just a random press release from a company selling boring old wireless kit. There isn't anything special about getting 5km of range with off the shelf wireless gear,

If anyone cares the math is not that hard to follow:

You take the transmitter output power, subtract any loss in the cable between the transmitter and the antenna, add the gain of the anteana. http://db.osoal.org.nz/eirp-calculator.html

Then you have to subtract the free space loss of your path ( the loss you get by putting the signal across the air ): http://db.osoal.org.nz/freespace-loss-calculator.h tml

And finally you add the recieve gain of the receiving antenna, subtract the loss from the cable on the recieving end and compare with the receive sensitivity of your wireless receiver. I have bundled the rest of the calculation into this bit of javascript.

For example, if I have two 2.4ghz radios that output 15dbm (32mw) that have a recieve sensitivity of -83db that are in waterproof boxes on the antenna mounting connected to two 22db antenna's 5km apart very roughly.

15db - 1db + 22db = 36db or ~3981mw (just under the 4 watt max).

- 121.65db for our free space loss

+ 22db - 1db = -64.65

-64.65 is the strength of the signal received at the other end, fortunately the receiver has a receive sensitivity of -83 so we are in business. There is a link margin of ~19db to account for a little bit of noise, fade, solar flares, alien abductions etc.

If you want more range, increase the power of the transmitter or the gain of your antenna. The government limits ( 4 watts for 2.4ghz, 250mw for 5.3ghz and 4 watts for 5.8Ghz in New Zealand ) are going to determine your maximum range barring some magical new wireless gear that has a better receive sensitivity.

I have no idea what release of Linux you are using, but I figured I'd try out a couple of things you mentioned in your post. Our desktop machines here at work run SuSE, they haven't been upgraded in a while so mine is still running SuSE 9.2.

I went and hunted about in the server room here at work for a USB mouse, and found an old microsoft one in a box of junk, I plug it into the front USB ports on my PC. A dialog box pops up which I have taken a screenshot of here:

http://db.osoal.org.nz/screenshots/new-mouse.jpg

The mouse is actually working at this point, and I can use it to click on the "Yes" button.

Okay how about changing resolutions, I click on the "Screen resize" applet in the tray and choose a resolution, it changes and a second later I'm looking at 800x600 rather than 1600x1200.

http://db.osoal.org.nz/screenshots/change-resoluti on.jpg
http://db.osoal.org.nz/screenshots/change-resoluti on-after.jpg

I agree adding USB devices and changing resolutions used to suck, it doesn't anymore.

I used to be quite mystified by people complaining about copy and paste on Linux until I went and used a windows machine for a few days. People in windows have to highlight, right click and select copy ( or the corresponding keyboard shortcut ). I have been using Linux for about 10 years now and for the whole time I have been highlighting text to copy and clicking the middle mouse button to paste. It works in just about everything on Linux. I can see that the windows method is totally busted across most Linux applications.

Configuring printers I agree is rubbish in Linux I have no problem with editing the cups config to add stuff, but the GUI frontends SuSE provide had me absolutely bamboozled the last time I tried.

Anyway just trying to add some more data points.

I have no idea what release of Linux you are using, but I figured I'd try out a couple of things you mentioned in your post. Our desktop machines here at work run SuSE, they haven't been upgraded in a while so mine is still running SuSE 9.2.

I went and hunted about in the server room here at work for a USB mouse, and found an old microsoft one in a box of junk, I plug it into the front USB ports on my PC. A dialog box pops up which I have taken a screenshot of here:

http://db.osoal.org.nz/screenshots/new-mouse.jpg

The mouse is actually working at this point, and I can use it to click on the "Yes" button.

Okay how about changing resolutions, I click on the "Screen resize" applet in the tray and choose a resolution, it changes and a second later I'm looking at 800x600 rather than 1600x1200.

http://db.osoal.org.nz/screenshots/change-resoluti on.jpg
http://db.osoal.org.nz/screenshots/change-resoluti on-after.jpg

I agree adding USB devices and changing resolutions used to suck, it doesn't anymore.

I used to be quite mystified by people complaining about copy and paste on Linux until I went and used a windows machine for a few days. People in windows have to highlight, right click and select copy ( or the corresponding keyboard shortcut ). I have been using Linux for about 10 years now and for the whole time I have been highlighting text to copy and clicking the middle mouse button to paste. It works in just about everything on Linux. I can see that the windows method is totally busted across most Linux applications.

Configuring printers I agree is rubbish in Linux I have no problem with editing the cups config to add stuff, but the GUI frontends SuSE provide had me absolutely bamboozled the last time I tried.

Anyway just trying to add some more data points.

I have no idea what release of Linux you are using, but I figured I'd try out a couple of things you mentioned in your post. Our desktop machines here at work run SuSE, they haven't been upgraded in a while so mine is still running SuSE 9.2.

I went and hunted about in the server room here at work for a USB mouse, and found an old microsoft one in a box of junk, I plug it into the front USB ports on my PC. A dialog box pops up which I have taken a screenshot of here:

http://db.osoal.org.nz/screenshots/new-mouse.jpg

The mouse is actually working at this point, and I can use it to click on the "Yes" button.

Okay how about changing resolutions, I click on the "Screen resize" applet in the tray and choose a resolution, it changes and a second later I'm looking at 800x600 rather than 1600x1200.

http://db.osoal.org.nz/screenshots/change-resoluti on.jpg
http://db.osoal.org.nz/screenshots/change-resoluti on-after.jpg

I agree adding USB devices and changing resolutions used to suck, it doesn't anymore.

I used to be quite mystified by people complaining about copy and paste on Linux until I went and used a windows machine for a few days. People in windows have to highlight, right click and select copy ( or the corresponding keyboard shortcut ). I have been using Linux for about 10 years now and for the whole time I have been highlighting text to copy and clicking the middle mouse button to paste. It works in just about everything on Linux. I can see that the windows method is totally busted across most Linux applications.

Configuring printers I agree is rubbish in Linux I have no problem with editing the cups config to add stuff, but the GUI frontends SuSE provide had me absolutely bamboozled the last time I tried.

Anyway just trying to add some more data points.

>What is going to happen if somebody creates a >mirror of these sites in a server operating >outside the jurorsdiction of a USA court
You mean like this?

As events like these at MIT show, and as slashdot quickly approaches a quarter of a million users, it's time for a slashdot reunion. Below is enclosed a list of the first 50 users, the folks who really know what it means to say, "I remember the good ol' days." How many of these users are still active? Reply, and show your true colors. The who replies with the lowest userid gets a prize! CmdrTaco (1) email: malda@slashdot.org
Hemos (2)
drendite (3) email: reishus@utdallas.edu
CowboyNeal (4) email: pater@slashdot.org
samzenpus (5)
jgoldsch (6)
CLorox (7) email: clorspam@marblehead.com
Emmett Plant (8) email: emmett@slashdot.org
keith (9) email: kcalder at andrew.cmu.edu
ximenes (10) email: sak8@po.cwru.edu
velkro (11) email: root@localhost
RAD Kade 1 (12) email: kmradlof@nospam@colby.edu
TechNoir (13) email: technoir@linux.com
Christopher Bibbs (14)
DeadBeef (15) email: spam@osoal.org.nz
Tom Rothamel (16) email: tom-slashdot@onegeek.org
Rolf W. Rasmussen (17) email: rolfwr+slashdot@ii.uib.no
davidu (18) email: davidu@angrywhitemale.com
steffenz (19)
Pug (21) email: pug007@sgi.net
jdesbonnet (22)
bounce@vegas.net (23)
Dorkman (24)
geNeV (25)
psychonut (26) email: lfd@NOSPAMsnip.net
francais (27) email: my1stname@mylastname.org
version conflict (28) email: cat /proc/kcore >> /dev/audio
jk (29) email: hns@scurvy.org
IAN (30)
Vadim Grinshpun (31) email: vg23@nospam.cornell.edu spidey (32)
ccg (34) email: ccg_spam at yahoo.com (just change 'at')
Crow- (35)
BOredAtWork (36) email: dsracic at vt.edu
smartax (37) email: br+slashdot@mindshark.com
David Rolfe (38) email: fromslashdot@shro0m.cx
Beirne (39)
michiel (41)
magg (42) email: mSaPgAgM@mail.com
Zack (44) email: zallison@rice.edu.spam
Ryan Kirkpatrick (45) email: slashdot@rkirkpat.net
Kadmin Kobolos (46)
euroderf (47) email: fred@moremagic.com
Mark Edwards (48)
sariman (49) email: ben@REMOVEsariman.net
jon (50)

Some people run web/ftp/mail servers etc. off dialup connections because it is the cheapest way of doing so while still maintaining control over the box.

-- DeadBeef
db@osoal.org.nz
http://www.osoal.org.nz

Some people run web/ftp/mail servers etc. off dialup connections because it is the cheapest way of doing so while still maintaining control over the box.

-- DeadBeef
db@osoal.org.nz
http://www.osoal.org.nz

I have posted some thoughts and screenshots of it running under Linux at http://www.osoal.org.nz/ in the comments section. Basically its very cool, seems to run ok in 1024x768 on my celery 333 ( with 2 8mb diamond voodoo II's ).