Friday, January 03, 2003
Cantenna Geekosity
The possession of the brain of an engineer, serious boredom, and restricted physical movement combines sometimes to drive one to trivial amusements, such as the following. Maybe some of you at least will understand ...
Ever since I first read about "Cantennas" (homemade wireless amplifying antennas, made from Pringles cans and suchlike), I have been curious and a bit confused, because while I could find lots of websites with information about constructing them, I could never find one that explained how you got the signal from the cantenna into your laptop. Vague references to pigtail cables with various connectors on the ends, but no good detailed illustrations or descriptions. I didn't know if you connected the thing to the wifi access point, or the cable modem (unlikely), or the NIC in the laptop itself, and in any case I didn't see HOW to do it, as at least for my own hardware, there are no extra connectors on my wifi devices. So I saved the pages with the instructions for building the antenna itself, and went as far as to empty, wash, and save a can that is close to optimal dimensions (diameter and length), but then I sort of forgot about it.
So today I decided to poke around some more. A little more luck this time -- I find a page that shows a cantenna sitting on a little mini tripod, plugged right into what looks like the laptop's wifi NIC itself ... it appears that the trick is to have a wifi NIC that HAS a connector that will take the signal from the antenna (via the pigtail) directly ... aha, I says to myself, but mine are connector-less, so what to do. I can't say as I am really in the mood to shell out for another 80211B NIC, since if I am going to spend new money on wifi, I'd rather go to 80211A or C or whatever the faster flavor-du-jour is.
But then I find this --
http://www.nodomainname.co.uk/SMC2632W/
Which is a page that shows how to take this particular model of SMC wifi card, and with such lovely tools as soldering iron and dremel rototool and xacto knife, cut the bastard open and modify it to accept a cable connector (the big idea being that for some reason, SMC built this card with a printed circuit board that INCLUDES mounting holes for just such a connector in it, but you just have to get through the casing to locate those holes and attach the connector). This page has a lot of detailed instructions, and photos, although a few of the photo links are broken for some reason.
But the kicker is that this is precisely the Wifi card that I already own, here on Fu, my trusty laptop.
Soooo, thinks I, an interesting experiment looms, and my interest is re-piqued in getting all nerdish and building myself a cantenna and so forth and so on. On the other hand, I am not real enamoured by the idea of cutting open this card just to play around with extending its range by lugging a soup-can antenna around the yard or down the street, or searching for other peoples' unencrypted hotspots to glom off of (living where I do, the geographical center of Geezer-Populated Nowhere, I probably have the only wifi connection in the neighborhood, if not the entire town, rendering an Aspect of Mootishness to the entire scheme -- but what the hell, if it's worth doing, it's worth overdoing, that's my motto). If I farked it up and hosed my card, I'd have to go buy another one anyway, just to get my un-cantennaed wifi to work again, or else return to the 100-foot-long Red Cat5 Wire snaking down the steps from the office and across the living room floor, to go back to wired-LAN use like I had before I bought the wifi in the first place. With a 3 year old and a 1 year old running hither and yon through the house at frequent intervals, I didn't like this idea any more now than I did the last time.
So then my brain thinks, wellll if this Wifi equipment is going obsolete as fast as it seems to be, maybe there are some identical SMC cards floating around for sale cheaply, like at eBay or half.com ...
et voila --
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20321&item=2085967928
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3710&item=2086044710
The auctions are both 6 days from ending, but neither had a bid nor a reserve, so I bid the lowest for both -- $5.00 for one and $.99 for the other ;-). I am sure those will go up, but I may just keep an eye out and if I could buy one for $20 or so, I'd do it, and hack into it without worrying whether I screwed it up or not. Heck, at that price I'd buy two or three, and keep them around in case of further wifi-age here at Casa Hillcrest.
Sooo, that was MY interesting thing for the day. You take what you can get ...
Ever since I first read about "Cantennas" (homemade wireless amplifying antennas, made from Pringles cans and suchlike), I have been curious and a bit confused, because while I could find lots of websites with information about constructing them, I could never find one that explained how you got the signal from the cantenna into your laptop. Vague references to pigtail cables with various connectors on the ends, but no good detailed illustrations or descriptions. I didn't know if you connected the thing to the wifi access point, or the cable modem (unlikely), or the NIC in the laptop itself, and in any case I didn't see HOW to do it, as at least for my own hardware, there are no extra connectors on my wifi devices. So I saved the pages with the instructions for building the antenna itself, and went as far as to empty, wash, and save a can that is close to optimal dimensions (diameter and length), but then I sort of forgot about it.
So today I decided to poke around some more. A little more luck this time -- I find a page that shows a cantenna sitting on a little mini tripod, plugged right into what looks like the laptop's wifi NIC itself ... it appears that the trick is to have a wifi NIC that HAS a connector that will take the signal from the antenna (via the pigtail) directly ... aha, I says to myself, but mine are connector-less, so what to do. I can't say as I am really in the mood to shell out for another 80211B NIC, since if I am going to spend new money on wifi, I'd rather go to 80211A or C or whatever the faster flavor-du-jour is.
But then I find this --
http://www.nodomainname.co.uk/SMC2632W/
Which is a page that shows how to take this particular model of SMC wifi card, and with such lovely tools as soldering iron and dremel rototool and xacto knife, cut the bastard open and modify it to accept a cable connector (the big idea being that for some reason, SMC built this card with a printed circuit board that INCLUDES mounting holes for just such a connector in it, but you just have to get through the casing to locate those holes and attach the connector). This page has a lot of detailed instructions, and photos, although a few of the photo links are broken for some reason.
But the kicker is that this is precisely the Wifi card that I already own, here on Fu, my trusty laptop.
Soooo, thinks I, an interesting experiment looms, and my interest is re-piqued in getting all nerdish and building myself a cantenna and so forth and so on. On the other hand, I am not real enamoured by the idea of cutting open this card just to play around with extending its range by lugging a soup-can antenna around the yard or down the street, or searching for other peoples' unencrypted hotspots to glom off of (living where I do, the geographical center of Geezer-Populated Nowhere, I probably have the only wifi connection in the neighborhood, if not the entire town, rendering an Aspect of Mootishness to the entire scheme -- but what the hell, if it's worth doing, it's worth overdoing, that's my motto). If I farked it up and hosed my card, I'd have to go buy another one anyway, just to get my un-cantennaed wifi to work again, or else return to the 100-foot-long Red Cat5 Wire snaking down the steps from the office and across the living room floor, to go back to wired-LAN use like I had before I bought the wifi in the first place. With a 3 year old and a 1 year old running hither and yon through the house at frequent intervals, I didn't like this idea any more now than I did the last time.
So then my brain thinks, wellll if this Wifi equipment is going obsolete as fast as it seems to be, maybe there are some identical SMC cards floating around for sale cheaply, like at eBay or half.com ...
et voila --
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20321&item=2085967928
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3710&item=2086044710
The auctions are both 6 days from ending, but neither had a bid nor a reserve, so I bid the lowest for both -- $5.00 for one and $.99 for the other ;-). I am sure those will go up, but I may just keep an eye out and if I could buy one for $20 or so, I'd do it, and hack into it without worrying whether I screwed it up or not. Heck, at that price I'd buy two or three, and keep them around in case of further wifi-age here at Casa Hillcrest.
Sooo, that was MY interesting thing for the day. You take what you can get ...
