Hi, I'm new here. Just installed my SMC Wireless Router and waiting for my Orinoco Golds for my laptop and desktop. I did searches for the last two days and I still have some questions. I am sure they could have all been found, but please just spare me

Also, I was wondering if anyone would mind taking me on as a "student". I'd like to have you as a mentor so if I ever have any questions I can email or IM you and ask. It wouldn't take too much time up and you can talk about what you love so it's not like you are "working." I have done this for many people in other topics I am versed in and always found it rewarding for both parties.

Questions.

1) Which of the follow are antennas used on? PCMCIA wireless cards, USB (for desktops, etc), or the actually WAP? Or all three? Which of the three do most people purchase antennas for? And if not all three, why not?


2) What does db refer to when speaking about antennas? The larger the value the better?

3) If there are many types of antenna (directional, omni, etc) why would anyone want anything but omni? Seems silly to limit yourself to just one direction ... unless you get increased range with the directional?

4) How is it possible that people in this forum are attempting to reach networks at their work/school from home, miles away. I know the range of 802.11b is no where near miles (300 feet is the max right?). I am 3-5 (depending where you stand) blocks from campus. Does that if I am at school with my notebook I can surf the net if my AP is at home?

5) When you use the pigtail to connect to the PC Card, doesn't it make for a flimsy setup? If the notebook suddenly jerks, I can imagine the antenna connector ripping out really easily. It seems to connect at 90 degrees and does not look too tight.

6) Can I make my SMC *not* broadcast?

7) Once I find a AP, is it just a matter of entering the SSID join the network? Does it require a reboot or anything?

8) Will Netstumbler work with any GPS hardware and mapping software?

9) Why is there such a big concern for stealthiness (sp?) when wardriving? I know cops are smart but I cannot imagine a cop pulling you over and accusing you of illegal activities. Alot of people have GPS, alot have notebooks and alot of antennas. I have seen many cars and trucks with a dozen, yes you read right TWELVE, antennas on them. Nobody cared, just stared a bit. Even so, the process of getting caught would be so long (meaning the admin would have to call the cops and give them an idea of what to look for, where, etc).

10) What are the major sniffers and what is the point? I assume only to decode WEP. Then what? Gain access to WEP AP's?

11) How many people does the SMC AP support? If I had 100 notebooks, would they all be able to go online?

12) What is an N connector? I think that's what it's called.

13) What is the purpose of wardriving and mapping esp in large areas like Silicoln valley. Do you honestly think that your maps will come out any different than the 1000's before you? I know new AP's pop up all the time or they go offline, but still. Also come to think of it what is the point of any of this? According to the messages, most of us don't even connect to begin with. So it's just to know it's out there? Oh I am not criticizing, in fact I will be joining your ranks shortly. I am just curious. Wouldn't an alternative be driving around with radios and finding out who has a cordless phone? No, we aren't going to listen to the conversations, but lets just note down where it is and map it.

14) What is some good / the best mapping software?

15) What is a reasonable GPS? Is the eTrex line good? The Legend looks to be ideal for mapping. Yes?

16) What is promiscuous sniffing?

That's it for now. Thanks for your help.

Note: I am not an RF engineer, nor a licensed ham, nor even a particularly clueful geek. The explanations of antennas given below are my best understanding, but may be technically inaccurate or completely wrong. They're still better than nothing, I hope, and someone will probably nitpick them anyway.

1: All of the above, assuming an external antenna connector is provided. Most PCMCIA cards don't include a connector, but some do. Some don't include one, but can be modified with a minimum of fuss. Most PCI adapters, USB adapters, and APs actually have a PCMCIA card inside. This means they only have to design the circuit board with the radio stuff once, and they only have to get FCC approval for one device. Some USB adapters are just a monolith that rely on the antenna built into the end of the PCMCIA card, some include a flip-up antenna with a few inches of cable inside that connects it to the card's jack. Almost all PCI adapters include an external antenna and a few feet of cable, since sticking out of the back of a desktop is almost never an advantageous position.

2: DeciBels. It's a logarithmic unit of signal strength. You'll usually see signals talked about with negative dB, so a -67dB signal is stronge than a -88dB signal. Most cards are sensitive down to about -104dB. Usually the "noise floor" is about -98dB though, and a signal won't be detectable unless it's stronger than the noise. The "Signal to Noise Ratio", or SNR, is the difference between the signal's strengh and the radio noise behind it.

2a: You'll see dBi, dBr, and dBm talked about, as well as just plain dB. They're all expressions of signal strength on a logarithmic scale. dBi compares the performance of an antenna to that of an _i_sotropic radiator. (More on that in a moment!) dBr compares _r_elative signal strengths to each other when no absolute reference is available. dBm compares a signal to a _m_illiwatt reference signal.

3: Imagine a telescope. A powerfully focused unit will bring the moon into clear detail, but you won't be able to see your toes. If you swivel the thing down to magnify your toes, you can no longer see the moon. Sensitivity in one direction is gained at the expense of other directions.

3a: Antennas are compared to a theoretical thing called an "isotropic radiator", which is essentially a boring antenna which radiates evenly in all directions. It has a spherical radiation pattern. It's agnostic to your position, but it's not very sensitive in any given direction.

3b: Real-world antennas don't need to behave like that, and indeed it's quite difficult to make an isotropic radiator. The vertical whip is an omnidirectional antenna. It has a radiation pattern something like a pancake, or a flattened donut. Which is to say, it's more sensitive to signals coming from the sides, but less sensitive to signals above and below. If there's an AP stuck to the ceiling and its antenna is oriented vertically, you'll get almost no signal from standing directly beneath it.

3c: Important point: By sacrificing sensitivity in some directions, you GAIN sensitivity in others. Let's say you have a fairly ordinary omni, like the little ones that come with PCI adapters. It's got a flattened radiation pattern, but not perfectly flat. Your best reception will be in the plane perpendicular to the antenna, but you can be a few degrees above or below it without much consequence. A "higher performance" omni will have an even flatter radiation pattern, more like a piece of paper than a pancake. The gain of an antenna is expressed in decibels compared to an isotropic radiator, assuming the measurement is taken in the antenna's "hot spot". So your favorite roof-mounted omni may have 8dBi gain, which will be great if the APs you're interested in are near street level. But if you're on the street and there's an AP in a skyscraper next to you, your reduced sensitivity out of the plane will mean you'll probably miss it.

3d: The much-ballyhooed Pringles antenna is an excellent example of a directional. It's very sensitive where it's pointed (about 13dB better than nothing) but ignores signals from around and behind itself. This has an interesting side effect -- if you point the antenna away from a noise source (such as your laptop), you'll see the noise floor drop. By limiting your selectivity, you can reject unwanted interference.

3e: To get even more directional, try a satellite dish. PrimeStar dishes are cheap, and they can make a very focused antenna. In the hot spot, it's about 25dBi gain, but because the spot is so narrow, they're a pain to aim. Suitable for fixed point-to-point links, you wouldn't want to use a dish for most stumbling. (However, parked on a hill adjacent to a city, a dish might be a great way to slowly scan the area without putting many miles on your car. Also, consider a parking structure a few blocks from a skyscraper, you could creep the antenna up and down the building.)

3f: The ideal antenna for stumbling would have a dog-bone radiation pattern. Consider the fact that there are no APs in airplanes above your car, nor in the sewers below you. There are also no APs in the road ahead of or behind your car. The only stuff you're interested in is to either side of the vehicle, as you drive past. As you turn a corner, the outboard side will sweep a good chunk of area.

4: Long-shot point to point links are possible by using absurdly directional antennae on at least one end of the link. For school, consider a satellite dish on your roof pointed at school, with the element mounted a bit out-of-focus so the spot isn't so pinpoint. You want to "paint" the whole school with signal, but not waste much on the neighboring property. You might be able to use a stock PCMCIA card for the other end of the link, if there's not much between you and the dish. (Walls, trees, stuff gets in the way.) To improve your chances, use directional antennas on both ends of the link. While you're at school, I doubt you'll be able to carry and aim a large dish, so try a Pringles can. It's directional enough to provide plenty of gain (mine gets about 13dBi) but the hot spot is broad enough to make aiming easy. Less sensitivity = more fudge factor.

4a: A friend and I tried out our Pringles cans on top of some parking structures. We were almost a mile away from each other, but getting about -70dBm with both antennae connected and pointed at each other. I knew this was more than 13dB above the sensitivity limit of my card (about -100) so I unplugged my antenna. The link stayed up, but it dropped to about -84dB. In this situation, his antenna was painting my whole parking structure with a broad hot spot, and it was hot enough that I didn't need special gear. This week, we hope to try a longer shot, about 2 miles. Being up above most buildings definitely helps.

5: It's not as bad as you might think. The right-angle mount reduces torsion from the (fairly stiff) cable, and the connector design can swivel freely, which reduces twisting. You're right though, it's a good idea to make sure there's not much stress on the connector. (Ideally, by affixing part of your pigtail to your laptop's body somehow, you can eliminate movement and stress on the connector altogether.) It's a good idea to reach over every few minutes and make sure the connector's still in snugly.

6: RTFM.

7: Most cards will let you put "any" in the SSID box and they'll auto-associate with whatever comes up. Then you just need to get an IP, which may be as simple as sending a DHCP lease request, which doesn't require a reboot. If the network doesn't have DHCP running, you'll need to manually enter an IP. Figuring out what to enter involves a sniffer. Win9x-based OS's want to reboot after manually entering an IP, but NT-based OS's and of course Linux can change IPs without rebooting.

8: Any GPS hardware that outputs NMEA-0183 formatted data. Garmin, Magellan, Trimble, most of the big names do this. Beware of deLorme and Sony, which use nonstandard data formats and only work with the bundled software. (Nice way to lock you out of using competitor's mapping software, eh?) Netstumbler doesn't interact with mapping software. People who map their APs do it after the fact, by parsing netstumbler logs and reformatting the data so that the map program can import the data points. Because of the way Windows handles comm ports, Netstumbler and mapping software can't both receive data from the GPS at the same time. Suck, suck. I work around this by letting my GPS record my track into its internal memory while I drive, so Netstumbler can monopolize the port. Then when I'm done, I fire up my mapping software and download the track log from the GPS, to show where I've been. Kludge!

9: Head to the "Other stumblers" forum and read my post entitled "Hassled by cops..." please. There's an argument for stumbling to be considered invasion of privacy and/or electronic trespass. I don't think it's valid, but I'm neither a lawyer nor a legislator. I consider netstumbling to be somewhere between CB tag, a treasure hunt, and cartographic surveying. It's certainly a good idea to be aware of radio signal sources near your home, and you might be able to play up the health-risk aspect to explain why you're measuring radio emissions. The important thing to consider is that cops are paid and trained to notice things that're out of the ordinary. Arrest first and ask questions later. If the cop thinks you're doing something wrong, and you can't make yourself sound harmless on the spot, you'll be stuck explaining your activities to a judge.

10: Decoding WEP is above and beyond the function of a sniffer, whose purpose is to receive and analyze packets on the network, not decrypt WEP. If the network doesn't have WEP, you'll be able to see other traffic on the LAN, not the least of which includes the IP addresses of the machines. See question 7.

11: RTFM. Realistically, a few dozen.

12: Most radio-frequency connectors have letters for names. The BNC is common in studio TV, but it's not suitable for the frequencies that 802.11b uses, which are pretty much microwave. The F connector can be found on all your cable-TV equipment, but it also sucks above a gigahertz. The N connector has been a staple of microwave ham equipment for years, because it's robustly constructed and performs very well up to a few GHz. They're also cheap and commonly available. (Ironically, "Radio" shack doesn't carry this radio component. Find a ham shop.) The function of a pigtail is to convert the oddball and expensive "MC-card" connector into the standard and cheap N connector, so you can build N's into all your antennas, then move the pigtail to whichever antenna you're using at the moment, without having to buy a bunch of MC-card connectors.

13: Visit the "AP information" section and read my post entitled "Amusing SSIDs" please. There are many and varied reasons. Some folks do it just for fun, some folks do it to steal service or for industrial espionage. Sometimes it's a social experiment. What's your reason?

14: Whatever you can get for cheap. DeLorme Street Atlas has an awkward user interface but it's bundled with their GPS units, and one of your friends can probably slip you a copy to try. Don't expect much though, I compiled a 2-page list of peeves after just a few days of using it. Microsoft Mappoint is also common, but I haven't tried it yet.

15: The eTrex line rocks, they're solidly built and very capable. Whoever does Garmin's firmware programming has too much time and skill on their hands, the suckers are packed with neat features. The interface is also surprisingly usable, only the silly "window menu" bothers me. Window metaphors don't belong on a screen the size of a matchbook. Ugh. Anyway, spring for one that includes the serial interface cable in the box. It's probably the same price as buying the cheaper model and then getting the cable separately, and the nicer model includes more internal memory and more functionality.

16: What your momma does on the street corner.

Whew! I'll try to help, but I'm sure these answers will cause you to have more questions... And yes, you will have to do some more searching! But since you asked nice, hopefully this will get you started.

1) All three devices can take antennae, depending on make, model, etc. Commonly on these forums, people are talking about adding an antenna to a PCMCIA card, because they are out in a mobile setup.

2) db is a measure of signal. In this case radio frequency (RF). The short answer is: higher is better. But be careful. This stuff is regulated by the FCC. Even though it is unlicensed, you just can't go hog wild. Don't even think about amplifying, until you understand the laws and regulations. You can get in a lot of trouble by exceeding the limits. I'd suggest some some introductory books to RF theory. Look for ham radio beginner books, that will probably start you off.

3) Directional antennae do increase range. They focus the radio signal. Think of it this way: A bare light bulb sends out enough energy to light a room, but not much beyond that. That same bulb behind a lighthouse lens will put out a signal that can be seen for miles, but only in one direction, in a narrow beam. Same principle.

4) Extended distance surfing is possible, but it will depend on the school's signal, antennae on both ends, etc. 802.11b stuff will reach over 15 miles in the right circumstances and equipment. But don't expect that. 300' is probably closer to the truth without a special setup of antennae, towers, high powered APs and amplifiers.

5) Pigtails are flimsly. You have to be careful. A tip I just saw this morning on these forums: Use a small paper binder clip on the card, over the pigtail connector. It will hold the connector in place and not let it swivel.

6) I believe the SMC uses the same AMTEL chipset as the Linksys and some others. Search on AMTEL and LINKSYS WAP11. That will get you a definitive answer.

7) Assuming and open AP and DHCP, yes just enter the SSID. You may need to take a PCMCIA card out and reinsert it. No reboot needed on any equipment I use, but your mileage may vary. A warning here: You might be in violation of local, state, and federal laws doing this. Best to have permission to connect, or make sure that it is a public network.

8) NS will work with GPS hardware that is NEMA 2.1 compliant. I use a Magellan Model 315. There is at least one thread on the "best" GPS unit. Look through that to see other people's recommendations. As far as mapping, NS does not actually "work" with maps. That is something added through scripts. NS outputs ASCII files, in one format. Several people have come up with scripts which convert that ASCII data into a format that works with some common map programs.

9) The big concern for "stealthiness" revolves around the fact that even if it is completely legal (I'm not getting sucked into that debate!) in some circles it might be considered the moral equivalent of looking through your neighbors' windows using binoculars. In one article I read, an Assistant Attorney General in Massachusetts said that he is actively telling the police to watch for and apprehend wardrivers. Clearly there is one prosecutor who believes that just wardriving is illegal. Nothing was said about CONNECTING to networks, only wardriving. Unless you have a clear and legal explanation of your activity, it might be grounds for an arrest or at least further investigation. It would be better to be stealthy at this time.

10) Sniffer programs grab packets. Packets are the means that information is passed via TCP/IP networks. Sniffer programs allow you to see the "raw" traffic on the network.

11) Check the SMC documentation and their website. Linksys says 30 connections for a usable number with the WAP11, which as I said, I believe is the same chipset. You might get 100 connections, but it might be so bogged down as to be useless.

12) An N connector is a connector for RF cables. Typically they are used on the antenna end. Most pigtails are a card connector on one end, and N on the other.

13)The point of all this... Hmm, you must be a philosophy student :-) Well, some here are clearly crackers, looking to "steal" bandwidth, while others here are obviously on the security side, looking to stop their networks from being cracked and used by outsiders. Some reside on a middle ground, something of the old definition of "hacker" and are doing it because it is interesting, and is the bleeding edge of computer & networking technology. They tend to be the "look, but do no harm" types. For some, the purpose seems to be little more that "Because I can, dammit!" The philosophers can debate whether that is a valid excuse for anything, and how it relates to the human condition. :-)

Finally the class I'm in, those people are those set up wireless networks for a living. Netstumbler is a great tool to survey what else is out there, and make sure that a setting up a new wireless network will not cause problems with existing networks. Personally, I'm one of those who will not connect to a AP unless I have permission to do so.

14) Depends on your price range.

15) See number 8. :-)

16) Some cards, using the appropriate drivers, will show all packets which pass though them. This is the "promiscuous" mode. In order to sniff (See #10) a card has to be in the promiscuous mode.

Cheers,
Thorn

Looks like Myself and I were writing at about the same time, and he posted first. If there is any dupication, its just due that. I wasn't trying answer Myself answers, only the orignal post.

Cheers,
Thorn

Questions.

1) Which of the follow are antennas used on? PCMCIA wireless cards, USB (for
desktops, etc), or the actually WAP? Or all three? Which of the three do
most people purchase antennas for? And if not all three, why not?

A1)All radios can have external antennas. but you may need to hack at the
plastic or pcb to give the capability for some radios. (A)external antennas
will fit on some pcmcia cards like orinoco. (b) the USB adapter/Radio also
has a pcmcia card on it but i havent seen any with external antenna
connections. You would need to cut a hole in the plactic to get to it.
(c)WAP has several meanings (WAP as Wireless access point) is just a
wireless AP working as a repeater(two radios in one AP recive on one and
rebro on the other)(orinoco and Intermec)

2) What does db refer to when speaking about antennas? The larger the value
the better?

(A1)(short version)DB is the strength of tx/rx power being produced by the
antenna with relation to power in milliwatts from the radio card. card=
+20db cable and connectors = -15db Antenna= +15db total = 20db

3) If there are many types of antenna (directional, omni, etc) why would
anyone want anything but omni? Seems silly to limit yourself to just one
direction ... unless you get increased range with the directional?

(A1)Distance is one. to cut down on noise with point to point. So you don’t overlap other channels when sending so reducing noise, better security when you only want a signal in a specific area.

4) How is it possible that people in this forum are attempting to reach
networks at their work/school from home, miles away. I know the range of
802.11b is no where near miles (300 feet is the max right?). I am 3-5
(depending where you stand) blocks from campus. Does that if I am at school
with my notebook I can surf the net if my AP is at home?

(a1) that is the distance with the standard 0db gain antenna. If you have a high gain antenna then you can reach up to 6km in Europe or 18 ish miles in the fcc area. You do this as it saves on phone bills and its also fun to play.

5) When you use the pigtail to connect to the PC Card, doesn't it make for a
flimsy setup? If the notebook suddenly jerks, I can imagine the antenna
connector ripping out really easily. It seems to connect at 90 degrees and
does not look too tight.

(A1)It’s the only way of connecting to your card with out hacking into your card and playing with the card.

6) Can I make my SMC *not* broadcast?

(A1) SMC??? I thought that was a connector

7) Once I find a AP, is it just a matter of entering the SSID join the
network? Does it require a reboot or anything?

(A1) it all depends on your system. You need to release and renew your ip address one you have the ssid in your card.

8) Will Netstumbler work with any GPS hardware and mapping software?

(A1) it works with my Haicom gps. To add it to a map you need to have a program or script to covert the readings to what the map understands. There are different scripts for different map programs. Map point 2001 doesn't work.

9) Why is there such a big concern for stealthiness (sp?) when wardriving? I
know cops are smart but I cannot imagine a cop pulling you over and accusing
you of illegal activities. Alot of people have GPS, alot have notebooks and
alot of antennas. I have seen many cars and trucks with a dozen, yes you
read right TWELVE, antennas on them. Nobody cared, just stared a bit. Even
so, the process of getting caught would be so long (meaning the admin would
have to call the cops and give them an idea of what to look for, where,
etc).

(A1) we are sneaky people and we would have to kill all cops that stop us...LOL. this means hacking is hacking. Hacking = jail....
mmm so tell me why you were outside the 1st nat bank with a computer radio equipment and the network name for the bank???? Gee sir I was testing my new gps...

10) What are the major sniffers and what is the point? I assume only to
decode WEP. Then what? Gain access to WEP AP's?

(A1) airosnort, airopeak, and more. They are all here on the web site. But it all depends on what OS you are using. Once you can get in the network you can use lan guard and find out passwords and computers and log in names. But for most of us it is just the fun of tryong to see if we can find a back door. And I am not talking about the one you sit on..

11) How many people does the SMC AP support? If I had 100 notebooks, would
they all be able to go online?

(A1) Orinoco supports 20, others only 7 and intermec will allow 254

12) What is an N connector? I think that's what it's called.

(A1) its to connection on a pig tail

13) What is the purpose of wardriving and mapping esp in large areas like
Silicoln valley. Do you honestly think that your maps will come out any
different than the 1000's before you? I know new AP's pop up all the time or
they go offline, but still. Also come to think of it what is the point of
any of this? According to the messages, most of us don't even connect to
begin with. So it's just to know it's out there? Oh I am not criticizing, in
fact I will be joining your ranks shortly. I am just curious. Wouldn't an
alternative be driving around with radios and finding out who has a cordless
phone? No, we aren't going to listen to the conversations, but lets just
note down where it is and map it.

(A1) 1 it’s a game. 2. its good to know where you can get on the web for free. 3. to see what is out there 4. to update the condition of an AP after say two weeks. It could have gone from no wep to wep so you leave that alone to get internet connection.

14) What is some good / the best mapping software?


(A1) You asked this???

15) What is a reasonable GPS? Is the eTrex line good? The Legend looks to be
ideal for mapping. Yes?

(A1) Again you asked this ??

16) What is promiscuous sniffing?

(A1) Receiving without sending

That's it for now. Thanks for your help.

Thanks for the replies guys. Someone should make this sticky or turn it into a FAQ.

More questions

1) If I was not wardriving and just wanted to extend the range between my notebook and AP, could I add antennas to both? I ask since everyone seems to like adding only to the pc card and not AP.

2) What is the best solution to this. I want to aim an antenna at my school so I can try to access it there while I am in the library or university center. I guess one that creates a sweeping directed signal would be good. Not a pringles can direct, but not omnidirectional either. More like a 45-60 degree ( just made some rough numbers up). The problem is I will only be at school trying to use my notebook say twice a month. I assume that if I hook up my antenna pointing outside my balcony then my connection while I am inside the house will be lost. Or would it? If I attach an extended external antenna, will the one on the AP itself deactivate? Like only one can be on at a time. Or would it essentially create two antennas? IF the AP one is deactivated, what is the best setup so both locations (inside house and at school) get access?

3) How come I cannot make my wap require some sort of login to join the network? It just automatically gives it to my notebook. I have WEP on using 64 bit manual. Hex keys were automatically entered. If I try doing automatic it asks for a passphrase. When I try to enter that pass phrase into the pc card it says that it's the wrong length. But the AP does not specify a length to enter.

4) Are there signal amplifiers? (Not antennas) Something to make the signal more powerful.

Thanks!

I had the same thought about the FAQ, and started in last night. ;-)

1) Yes, you can (probably) add an antenna to the AP. It depends of course, on AP brand, connectors, etc., but it can be done in most cases.

2) Unless the AP has a dual antenna design, you don't want to add one outside the house, and leave the second inside. At best, you'll just get bad reception on both, at worst, you might damage the AP's radio.

Suggestions: A) Check and see if wireless is already at school. You'll save yourself some effort if it is already there. B) Add wireless at school with some other people. This stuff is easiest with other geeks. And you might be able to hook into the school's networks with their data pipe. C) If you do end up running a link to your house, just plug a directional (panel, patch or yagi) in while you're at school, and plug in a small interior omni while at home.

3) A "login" requires a bit more than just an AP. You need a computer that does some authorization. APs tend to fairly simple devices in regards to the network. Think of an AP as a hub that only needs wire one side. There are several Linux freeware programs that can do authorization (NoCat at nocat.org, is one) as well as some $$$ Windows programs.

As far as the WEP goes, it is generated by the passphrase on many APs. If the manual doesn't specify this info, check the manufacturer's web page.

4) Short answer: Yes, there are amps. Much $$$$. But even if you an afford it, you are way too new at this to try an amp, IMHO. Amps add as much noise as they add RF signal strength, and require a at least a minimum amount of RF knowledge to get right. Learn and master the basics first. You have to know the limits, how to compute the signal output, based on antenna gain, line losses, connector losses, etc., etc. The math isn't difficult, but you do have to know it.

Two things to keeps in mind about amps: First, if you exceed limits of power, you are begging for a visit from the FCC (if you're in the US.) They recently doubled their enforcement budget. They may not get you, but do you really want to chance becoming the "Illegal Wireless" poster boy?

Second, in the professional wireless networking circles (the guys who ought to know a thing or two about this stuff,) amplifiers are considered the absolute last resort because they amplify the noise as well as the signal. If the pros avoid them, you should until you at least know a bit more about how it all works.

Cheers,
Thorn

... here are some more questions!

1) If I cannot do a dual antenna setup (one inside and one outside), then what is my alternative?

1A) I cannot get wireless at school. They are too cheap. Other schools have nearly the whole campus wireless, but not my school. In fact they wired one department and took a year to say it was a success. I can't imagine how long it'd take for the rest of the shool.

2) If db is a measure of strength, the higher the better right? So -85db is better than -100db?

3) How come they are listed in negative values. How can you have negative signal strength?

4) I won't touch the amps, promise

Thanks,
Sygyzy

sygyzy,

1) About the dual antenna arrangment, try suggestion C above, and quoted here again. It is not elegant, but it does work. "... just plug a directional (panel, patch or yagi) in while you're at school, and plug in a small interior omni while at home."

1A) Grassroots movements and clubs are known to work. See if others are doing this or at least interested. I would be willing to bet you're not the only one on campus who wants this. Find an "alpha geek" or two.

2) Yes, -85dB is better than -100dB.

3) As to why these numbers are negatives: dBi is a logarithmic function. The radio power is in milliwatts which is (10E-6 watt) so you end up with a negative number. (That answer is probably too confusing.) For a very comprehensive paper, look here: http://www.columbia.edu/~fuat/cuarc/dB.html It is pretty straight forward. Don't get scared by the math. The stuff you want is at the bottom.

4) Good. Look at the amps when you know more. At this rate it won't be too long! ;-)

Cheers,
Thorn

Thorn,

Your suggestions for the types of antennas to use while at school and while at home - they both are for connecting to the PC card right? Not the AP? If so, why is that? I assume that means you are saying that in a perfect situation the AP can shoot out a signal for vast distances and it's the weakness is on the side of the notebook. Is that true?

Where would you recommend purchasing antennas? I think I'll have to pick some up.

Thanks,
David

No, I meant an external antenna for your AP outside your house when you are at school, and swap to an internal antenna when you are home. But you do bring up a good point, for any real distnce you will probably need an antenna on your PCMCIA card. The card antenna is usually just printed circuit, so it is hardly the best.

Look here for the external AP antenna:
www.superpass.com

and here for an laptop card antenna:
http://www.antennasystems.com/broadband.html

There are other suppliers out there, but I've dealt with both and was very satisified with them. Superpass in particular is very good about answering questions.

Of course you will need some cable and pigtails. A pigtail is the card-to-cable adapter. Search through these forums, there is a load of info on pigtails.

Cheers,
Thorn

drodge

Try: www.antennasystems.com

They have tons of antennas from omni's to yagi's and everything in between. They also sell pigtails, cables, etc

To clarify some points made earlier, you do have to be careful about increasing output power. The FCC has guidelines about max output. In extremely simple terms, the more directional your antenna is, the more watts you are allowed to put out. This keeps spectrum hogs from putting up outragous antennas that would drown out other signals. If you want specifics about how much power you can use, check out the FCC's web site.

As someone else pointed out, the FCC does have enforcement agents. If someone notices that your output seems high, all it takes is a phone call and they will send someone out to take an RF measurement. They usually just issue a warning the first time and explain the rules. But, the fines go as high as $20,000, so don't go crazy.


If you want to experiment with directional antennas, there are tons of sites on how to build a yagi antenna or a dish using an old satelite system. Check out Freenetworks.org and it's affiliates and search for antennas to find more info.

Also, on a good note, it's good to see people helping a out a newbie for once without all of the stupid crap. We were all there once.

Thorn

Thanks. The trouble is that this thread was done about 4 months ago, and some newbies seem to take the time to read anything; Nevermind something that old.

I can't think of anyone who has been here for any length of time who will not answer a legitmate question. The problem is that many newbies obviously don't read anything like the FAQs or the README.html. They ask the same questions, ie "Why won't my Linksys card work?" which are answered in those douments. and then get upset when they get an "RTFM."

BTW, I did mention Antenna Systems in my last post.

__________________
Thorn
"Read Altas Shrugged. Compare it to today. Repeat as necessary"