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Cringely's Bank Shot
Michael A. Lowry writes: "You may remember how Robert Cringely used a couple of directional antennas to get an 802.11b link up across a 10.5 km wide valley. The original Slashdot discussion is here. Well Cringely has done it again. This time, he has set up a passive repeater in an oak tree on a nearby mountaintop to bounce a 2 Mb/s signal around a hill that lies between his house and the acces point in Santa Rosa. Read about it here. Details about the homemade hardware he used can be found here. There's going to be a lot more of this in the near future."
It's passive. No power needed. Basically, a wave received from one antenna will travel down a transmission line to an antenna connected at the other end and radiate out (and vice versa) with very little loss.
For those moderators not paying attention, the parent post is an obvious troll.
This is precisely why we need the FCC to regulate people's use of this equipment.
Cringely's setup is regulated by the FCC and is within FCC specifications. There is nothing illegal (as far as the FCC is concerned) here.
Did Bob Cringely ask a single person living in downtown what they thought of his terrific internet access plan?
Why would he? Does the neighborhood get a vote every time someone turns on a cell phone? What about when a ham radio operator fires up his 1,500 watt amp? What about when someone turns on a microwave oven?
What about the those people who use approved wireless equipment (phones, wireless networking) and now have to deal with the background noise
Cringely was using an FCC type-accepted device well within its specifications. Did you miss that part of his article?
coming from his souped up repeater?
His 'souped up repeater', as you call it, is a couple of antennas back to back. It's passive. His antennas don't put out power, they just focus the energy. With 18db of gain, his 100mw signal is still under five effective watts.
Wait, I'm sure he did a thorough study of his setup to make sure that it didn't interfere with transmissions by public safety agencies, right?
Dude, take a basic radio class. He isn't changing the operational frequency. He isn't using an illegal amp that might cause out of band splatter. His third order distortion won't be affected by a passive antenna. There is harmless.
What stopped him from using a 10 watt transmitter, so that the connection would be even faster?
If he had a ham radio license, he could legally run up to 1,500 watts of power, operate an active repeater and use whatever antenna array he wanted all in the same frequency range he is using now. As an added bonus, he still wouldn't have to fill out any paperwork, get any government approval or take a poll of his neighbors.
Follow the rules and don't subject other people to your homebrewed technology.
Once again, other than unlawful use of a tree for the purposes of geekness, I he hasn't broken any rules.
If you want to learn something about radio (and, trust me, you're really ignorant now), why not surf on over to the American Radio Relay League. They represent hams across the world. They have some very good teaching materials. If you study hard, maybe you can even get a ham license. It really is pretty nifty.
InitZero
I myself live in a bandwidth black hole which I just happen to be in the center of. So, I actually started researching and buying gear to hook into work's T1, which is about 4.8 miles away. The gear I decided on was two Orinoco (or WaveLAN as they used to be called) cards with Linux boxes to match to keep costs down (besides, Linux makes for a great wireless router). My antennas are 24dBi gain Hyperlink parabolic grid antennas. I already have the cards working in my Linux installations and am ready to hook up the antennas soon. The only tricky part is that my path to work is slightly obscured so I'm hoping I have enough power and gain to be able to punch though. Hopefully the bandwidth gods will look favorably upon me. I've never had a high speed connect at home (and probably never will if this doesn't work :/)
:)) I also asked how he got around mountains and such.
One of the coolest projects I found while researching this was the HPWREN project at UCSD. Check out their pictures, it's hella cool. In a nutshell they are running a 45Mbps (802.11a) wireless backbone across the Santa Margarita Ecological Reserve using mostly off-the-shelf equipment, for the purpose of hooking together the facilities strewn across it. They even have remote cameras hooked in that can be remotely controlled through the network, and other testing stations that send data back to them in realtime.
I dropped an email to the project lead and I asked him what kind of gear they used. He said they used a Western Multiplex Tsunami for their backend, Hyperlink for their antennas and WaveLAN and Cisco Aironet for their PCMCIA cards (you can now see how I constructed my parts list
Well, in certain places they have powered relay stations. Naturally I wondered how they were powered, and he said some of them they could get electricity to, but others they actually have solar panels powering the relays. Damn. For you real hackers he mentioned there was a parts list for the solar power array somewhere on the website, but I never bothered to try and find it.
I've noticed some arguments regarding amplifying 802.11, and thought I'd help clear it up. FCC Part 15.247 governs the unlicensed ISM (Industrial, Scientific, Medical) band, and dictates that you can amplify the signal up to 1 watt (1000mw) This gets tricky when you start using directional antennas >6dBi gain though. You may find more detailed info here..
-R