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FCC Allows Mix-and-Match Wi-Fi Antennas
Glenn Fleishman writes "We just filed a story at Wi-Fi Networking News about how the FCC recently and quietly approved rules that will allow the legal use of the Pringles can and other antennas. Currently, it's clearly illegal--even though it's incredibly easy--to swap out a manufacturers' antennas from a Wi-Fi access point with an antenna of your choosing. It's legal to sell antennas; not legal to deploy them. Call it the switchblade kit rule: legal to sell, but don't assemble. The FCC's new rule provides a middle ground: a manufacturer can certify their hardware with the highest gain legal antennas of each type (yagi, omni, etc.) and then end-users can swap in antennas of equal or lesser signal characteristics. It's an important move because it removes the potential for community wireless and individual users to be prosecuted for illegal antennas once new certifications are in place."
Does this mean that we can finally get rid of annoying antenna connector types such as RP-SMA and RP-TNC that were originally devised just to make it a pain in the ass to switch out factory antennas? I'd much rather be able to mix and match antennas and cables that can be easily found at local HAM shops.
How is it clearly illegal? I didn't know it was illegal to use your own attenas? Was it illegal to put a coat hanger on a walkee talkee with a broken antenna?
They realized that such a restriction with small wireless networks would be very difficult to enforce. Or maybe they like the idea of community wireless networks without buying expensive equipment?
and then end-users can swap in antennas of equal or lesser signal characteristics.
does that include range? cause if so, it kind of defeats the purpose, right?
i didn't RTFA.
This can't be happening!
Curb CO2 emissions: Kill yourself today!
you can also use a peice of cardboard and aluminum foil http://www.techtastic.ca/articles/homemade-antenna .html
Does anyone know of the current legal status of these antennaes in Canada? I would hope that the Canadian legal body that controls the airwaves (CRTC?) would agree with the new ruling.
Call it the switchblade kit rule: legal to sell, but don't assemble
Fully offtopic, but why are switchblades illegal in the U.S.? Is this a throwback to the 1950's era biker/greaser hysteria?
Jason.
Doesn't this mean quite the opposite - if you have an antenna of questionable legality right now, after the certifications are in place it will become an uncertified and illegal antenna?
Has anyone ever been sued for WiFi antenna gains in the past 5 years? If not, then keep the pringle cans flowing.
GroupShares Inc.
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artlu.net
Channel 1 is in a band that falls in spectrum assigned to amateur radio operators. That means, of course, we can legally transmit up to 2500 watts vs 50 milliwatts if that happens to be the lowest power we need to get the signal through.
It also means we're licensed users of the spectrum, which trumps Part B and means a license holder could, technically, tell a neighbor to move off of channel 1.
The Article: With bongs the case is that you can sell them, own them, use them, whatever, but not for illegal drugs, only tobacco and other legal smokables. What this means is that while it is generally legal to sell bongs, if you're selling stuff like pot leaf print wallets and shirts, etc. or the store's name is "Drug Paraphrenalia 'R' Us", you'll get taken down for drug paraphrenalia. Similarly, if you have a bong that you're clearly using only for tobacco (i.e. a turkish hookah), then it's entirely legal to own and use it. However, things that have no legitimate consumer purpose other than drug use are outlawed across the board (i.e. crack/meth pipes and tie-off bands for heroin and other IV drugs).
I noticed that the article lists a bunch of different antenna types. I didn't know what they all were, so I looked some of them up and thought I'd share:
m l
The info in quotes is verbatim from http://www.radiolabs.com/Articles/wifi-antenna.ht
Omni: (Omni-Directional)
This is a standard antenna like you'd see on a cordless phone. Broadcasts the signal more or less equally in all directions.
"An Omni-Directional antenna would serve as your main antenna to distribute the signal to other computers or devices"
Yagi Antennas
"Yagi antennas were the design of two Japanese people, Hidetsugu Yagi and Shintaro Uda, and are sometimes referred to as Yagi-Uda antennas...these antennas are typically very directional and are used for point to point."
Yagis look like a ladder with one vertical bar in the center of each step.
Backfire antennas
"The backfire is a small directional antenna with excellent gain. They look similar to a parabolic dish, but the gain isn't as high."
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DrMovieMovie.com:
Witty movie reviews, eating contests, and a guy who once drank a gallon of milk in an hour.
it removes the potential for community wireless and individual users to be prosecuted for illegal antennas once new certifications are in place
No it doesn't. How'd you come to that conclusion?
If a user has an antenna that exceeds the specs that have been certified for that antenna type with that device, it's still illegal to use and the user can still be prosecuted.
And if the manufacturers don't get their devices certified with anything other than their weak default antenna, you still won't be legally allowed to use anything stronger than their default. This will vary by manufacturer -- Linksys might want to sell powerful upgrade antennas to its users, so it will get its equipment certified with a really powerful antenna. Apple, on the other hand, probably has no plans to sell replacement antennas for its Airport devices and will only get certification for its standard antenna.
The FCC regulations have kept me at bay in question in regards to their limitations put upon the technology.
:) -- oh and yes, that mile and half point to point I just put together has turned out BEAUTIFULLY - email me if you want details! -- let's just say WRT54G omni antennae, WAP54G directional antennae, and sveasoft! works wonders :)
Being fairly savvy in the wifi arena - I have quite often wondered what was legal and what wasn't...so I have done my best to stay within the legal parameters....yet - someone needs to put together a good chart of what certified equipment is 'legally' compatible with what.
Just my humble opinion
If any one wants to use highpower 802.11 on 2.4gh and use huge wave guide antenas with that high power equipment then all they have to do is get a ham lisense. With the introductory lisense you can use super high power out put transmitters and realy high gain antenas compared to the comercialy avable stuff. How would you like 100 wats PEP on your access point? The only thing is you cant use it for comercial purposes only personal uses. If you get the liscense you also get access to other bands and you can legaly build your own radio equipment. Its not hard to get the lisence either and there are probaly tons of hams in your area to help you get into and promote radio hobbies like packet radio. Check out www.arrl.org, or www.qrz.com if you need some more information.
Faith_Healer -- The antethsis to almost everything, and the worlds worst speller.
I didn't have a problem with the existing ban on altering antennas. The hazards of increasing the power of 2.4Ghz is not something to be taken lightly. Isn't that the same frequency that water resonates at (same principle as a microwave oven)?
I wonder if Linksys pushed some buttons following the relase of their new antenna to get this done so quietly?
Why would the FCC worry about the gain on these antennas? The transmitter can only pump out so much juice, and as far as I know the gain of the antenna can't boost the TX power (only direct it), and only the amount to power that is RX'ed is boosted. Someone please explain why High Gain antennas are/were evil to the FCC?
md5sum
d41d8cd98f00b204e9800998ecf8427e
JULES -- okay now, tell me about the WiFi bars?
VINCENT What so you want to know?
JULES Well, WiFi is legal there, right?
VINCENT Yeah, it's legal, but is ain't a hundred percent legal. I mean you can't walk into a restaurant, take out your laptop, and start downloadin' away. You're only supposed to download in your home or certain designated places.
JULES Those are WiFi bars?
VINCENT Yeah, it breaks down like this: it's legal to buy it, it's legal to own it and, if you're the proprietor of a WiFi bar, it's legal to sell it. It's legal to carry it, which doesn't really matter 'cause -- get a load of this -- if the cops stop you, it's illegal for them to search you. Searching you is a right that the cops in Amsterdam don't have.
JULES That did it, man -- I'm fuckin' goin', that's all there is to it.
VINCENT You'll dig it the most.
I smell a rat here...looks like a gradual weakening of Part 15. I've always been amused at the blatantly (in some cases) illegal experimentation with 802.11 gear to get the max gain and range. Not that I have a problem with experimentation, but if you want to exceed what's legal with Part 15 then you should get a Tech ticket. Now that won't be an issue. Anyone see a parallel to BPL? I'm waiting for the day the FCC changes Part 15 to redefine harmful interference, as it pertains to BPL only. Then we'll be the ones with our asses in a sling when our HF QSOs knock out the neighbor's broadband porn, not the other way around.
8 bit computing - It may be 2007 out there, but it's 1983 in here!!
It was never clearly illegal to change antennas. If you were already near the maximum RF power, and you used a high gain antenna you may required to attenuate the signal, but not by as much as the gain. A quick search shows that in America you have to have an antenna gain over 14 dB before you have to start cutting power.
Many WiFi products are low enough power that you couldn't violate the standards with any antenna.
The blurb states, "FCC recently and quietly approved rules that will allow the legal use of the Pringles can and other antennas." This is clearly false, since those antennas were already legal to use.
Posted anonymously for avoidance of karma, snootchie bootchies
Switchblades aka automatic knives aren't illegal to own in most states. The law varies from state to state, and in Oregon, they are legal to buy and carry as long as they aren't concealed. The way most states work is that you cannot buy a switchblade, nor carry one unless you are a member of active law enforcement, military, or only have one hand/arm. But owning one as part of a collection is legal in most states. You are correct though, it's stupid to ban carrying switchblades. I live in Indiana. I can legally carry a concealed handgun capable of killing 11 people, but I can't carry a knife that opens when I push a button?
Mod points are pointless when you browse at -1.
Finding the people with potato-snack antennae may be difficult, but enough prosecutions would make it less attractive to most people (deliberate outlaws/nonconformists excepted). The availability of certified antennas would remove the necessity.
Sustainability and energy independence essay
I mean, sure, if you can show your antenna is lower-gain than the approved one, no problem... but then, why would you have switched to your lower-gain one?
No, I didn't RTFA. Anything with FCC in the title makes my head hurt.
so they struck 15C 15.204(c) which is the only provision which might even potentially make it illegal to use an additional antenna (all other regulations are about sale, distribution, and marketing). Besides which 15C 15.23(b) already hinted that you could build/modify your own equipment so long as you made a good faith effort not to interfere.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
This means that the listed performance characteristics (coverage pattern and gain, primarily) for access points will become basically useless while shopping for AP's because the numbers that the manufacturer uses in their specifications will represent "best case" antennas. At microwave frequencies, even tiny variations in the antenna can make a tremendous difference in its performance.
There have been problems for years in the ham radio arena with manufacturers advertising gain values for antennas which can't be duplicated by real-world users. The ARRL's magazine, QST, refuses to accept ads which list gain values for this very reason.
The make shift antenna that I made out of speaker wire for my home stereo system is illegal. Or that possibly doesn't count cus I ain't transmitting anything but honestly, how many people use the actual antenna that comes with your stereo?
In fact, here in Southern California some of the shops that cater to Marines and Sailors openly sell switchblades. They require you to show a military ID.
Similarily, duct tape is currently in extremely high demand, causing many stores to institute duct tape rationing.
One consumer, who would only identify himself as "D0k+04 1337" is actively protesting the rationing.
"Sure, it's a conspiracy, man. I mean, what good are Pringles cans without the duct tape? It's just the man keeping us under control."
We all get along together like tornadoes and trailer parks.
Well, I can almost understand not RTFAing, but you didn't even correctly RTFBlurb.
"a manufacturer can certify their hardware with the highest gain legal antennas of each type (yagi, omni, etc.) and then end-users can swap in antennas of equal or lesser signal characteristics."
The manufacturer will certify a product with the highest legal antenna of each type, then sell you the product with their normal low-gain antenna. As a manufacturer, would you rather sell a product with a $0.05 antenna that can only work over short distances but for 90% of users, or would you rather advertise that it is certified to use MUCH higher gain antennae so that it will work for 99% of users (and still use that $0.05 antenna)? Essentially, for the cost of certifying one test item and the cost of a sticker on the same box, you gain a larger percentage of possible buyers.
IANAL, but I play one on
...and then end-users can swap in antennas of equal or lesser signal characteristics...
Doesn't this make this practically useless for most purposes? Who would willingly swap an antenna for a less-powerful one? The only benefits I can see here are replacements for broken antennae and perhaps homemade solutions for connectivity.
I don't really see how this would legalize the Pringles Can. (Imagine how strange that sentence would have looked ten years ago...) Unless the Pringles potato chip company decided to petition the FCC to certify their cans as antennas, they would still be illegal, uncertified equipment, even if they were weaker than some FCC-certified antennas.
Wok Scoop Wifi antenna
Jon Bardin
My point/question is that if you aren't buying the "approved" high-gain antenna, or are using one of a unknown characteristics, aren't you more obviously in violation of FCC rules, making your prosecution a bit easier?
Though, if you're using a pringles can covered in foil, I guess you're pretty obviously in violation anyway...
There are federal laws that prohibit interstate transport of automatic knives, however in most states they are legal to purchase in buy, and in many they are legal to carry with some restrictions. Here's a list by state: http://www.amatecon.com/switchblade.html
The pringles can antennas work really well. I've built two of them. There's plenty of really good guides on how to make the antennas and how they work.
2.45 GHz is not, and has never been, the resonance frequency of water. But it is the frequency on which microwave ovens operate. But there is also ovens at 900 MHz etc.
(I could paste the link again, but a quick search of the slashdot archives should give you rich information about why this is true...)
MP isn't evil. He's actually had, from the little that I've paid attention to his policies, a strong tradition of helping out techies and little tech companies, and minimizing government interference -- the sort of thing that makes most Slashdotters happy. He was concerned enough about the fact that independent techies and hobbyists weren't being represented that he set up a weblog. He's one of my better-liked bureaucrats.
He got a *lot* of flack for condemning Janet Jackson for flashing her breast. That was unfortunate, because he got blamed for something that, well, really wasn't his fault. The existing laws prohibit JJ from doing what she did -- his irritation was over the fact that the laws that are part of the FCC's jurisdiction were being ignored, and conservatives were saying "Hey, this guy isn't enforcing our laws". MP didn't *make* the decency laws (that goes back to, oh, I don't know, the '50s, perhaps). The problem is, frankly, really stupid values from a lot of Americans that think that nudity is a horrible, awful thing. Don't blame MP for enforcing the laws that Americans asked for, and existed when he got into office. If he just ignored them, he'd be out of office in no time. Blame poor American values WRT nudity. That's what would have to change for decency laws on TV to go away, not Powell being replaced.
May we never see th
The guidelines say its ok, as long as the antenna isnt shaped like a breast.
This comment does not represent the views or opinions of the user.
OK, I see your point now. I think you are in the same boat as me with respect to our knowledge of antenna designs. I'll see if I can get my friend to reply to you and give better info than I can.
The way I understand it is that certain antenna designs have theoretical maximum gains and ERPs. A Yagi made in the best possible way with the best possible components will give you this gain and ERP. The company would then certify for THAT design (or as close to it as possible if they have to do real-world tests). If it is certified for a Yagi of the highest specs, then any Yagi will work. As far as pringles cans go, I don't know if that has a technical design name or if you can buy pre-manufactured ones, etc.
I think by legalizing the use of specialized antennae, they are trying to shift the production of them over to bigger businesses and keep control over the area in their own hands. Feel free to poke holes in that idea.
IANAL, but I play one on
You know if you go get a Technician amateur radiolicense you can use the access point under part 97 rules instead of part 15. You can use the lower channels that fall within the HAM allocation, with amplification (up to 100 watts subject to erp limitations) and any damn antenna you want. Use transverter to move up or down to ham only allocations and now a plain old part 15 user can't intercept you. You just can't use encryption or surf pr0n as it would be a decency violation.
The test is easy to pass. All the questions and answers are available from the FCC and other websites. There is even a test generator that will score your answers online, at http://www.eham.net
Oh, you have to pay a fee to take the test. When I did it it was something like $10? It was so cheap I don't recall exactly.
If you don't have any training or experience and someone pulls a knife on you, my advice is to run. Likewise, it's best to not use a knife if you have no training or experience. Someone may take it away from you and stick you with it.
-cp-
Do what I did, get your amateur radio licence. Then you can do pretty much whatever you like. At least in Canada that is.
This is a mixed bag-- you can't certify an "ideal antenna design," because ideal antennas are only that for a specific frequency. WiFi covers a range of frequencies in the 2.4GHz ballpark.
It would be possible to build an antenna of the same design type as a certified one, but tuned so that its gain is outside of the legal bounds on a particular channel or two. This could be as simple as making an antenna more directional, or by changing the distance between the little cross-pieces on a yagi. So even though it's still a yagi, or still some sort of parabolic dish, or whatever, it could be outside of spec.
So they test, certify the specs, and then require you to buy one that's tested to lesser specs.
I doubt it's any sort of real conspiracy-- it's just the radio-folk worried about us crapping radio waves all over the place at levels we're not allowed to. If you want to make a lot of wifi noise, get a HAM license. Some of the lower wifi channels are in the HAM range, and you could feel free to run your access point at hundreds of watts.
But I'm no expert-- just a bored engineer with limited radio knowledge. We really need a radio engineer or a salty old HAM to post to clear it up for all of us.
It's pretty hard to exceed the legal limit for antenna gain with a pringles can (unless you're using it in conjunction with an amplifier). 15 dbm card + 12 dbi cantenna = 27 dbm effective radiated power, which is significantly less than 36 dhm erp (4 watts), which is the limit for most applications.
See also part 15 section 23 (home built devices), which seems to imply that its perfectly okay to build your own custom antennas in some situations regardless of what the article says.
-jim
Switchblades aka automatic knives aren't illegal to own in most states. The law varies from state to state, and in Oregon, they are legal to buy and carry as long as they aren't concealed.
I think they're also allowed concealed under the same on-demand licensing as guns. (But I'm not an Oregonian so check that if you want to carry one.)
It's interesting WHY they're legal in Oregon:
Oregon has had legal open carry of guns for a long time, and on-demand licensing for concealed weapons carry as well. It also has a provision in its constitution that it can't pass laws that penalize some social and economic classes and not others.
It had an anti-switchblade law, like much of the rest of the US. But a person being tried for violating it argued that he could have carried a gun in the same way, which would have been at least as dangerous, but that guns were expensive and switchblades cheap. So the law was discriminating by income level, denying the poor self-defense options that were afforded to the more well-to-do.
The judge bought it and the law was thrown out.
(Interestingly, gun control in the US has always been about denying self-defense to the lower classes. But that's another thread.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
(Interestingly, gun control in the US has always been about denying self-defense to the lower classes. But that's another thread.)
Knife control - especially switchblades, too. Specifically, certain immigrant waves (such as poor Itialians around WWI - WWII) who used it as their personal protection "weapon of choice". (And thus whose criminal classes would commonly chose it for intimidation, since carrying it would let them blend with the crowd.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
So, if this passes, and the INDUCE act passes, would Pringles now be in deep shit for making their cans that can be used to break the law?
Well I didn't know that. I should get a switch blade and not assemble it.
I should also order an AK-47 kit and not order the missing receiver through some place else or have some manufacture a custom one for me cheaply. (yes you too can have an fully automatic illegal assult weapon for under $200, as long as you don't assemble it).
Funny how the same place also carries high capacity magazines, ammo and drums for that particular fire arm. but you're not suppose to have any of this stuff. (Sorry won't ship the mags to california, you'll have to buy them at a local gun show for half the price).
“Common sense is not so common.” — Voltaire
...drat I say... got a three meter dish hanging out in the weeds over here... I been eyeballin that bad boy for a few now....... %^)
They make the most money by loaning mortgage "money" that doesn't exist. They are allowed to issue it after having a certain small percentage in actual cash reserves.
www.cantenna.com This was brought up in a chat the other day as we were discussing wiFi options. I read another story (can't find the article now) about a man who set up his own antenna, to get internet from the Starbucks several blocks away.
Couple of starter points:
... with the advances in aerial technology I wouldn't be surprised to find that someone has designed an antenna array that can figure out the direction that it receives the strongest signal and then chooses to use particular aerial elements to send back a signal, using just those elements pointing in the right direction to allow the maximum power to be "beamed" in the right direction.
1) There are two antennas involved, the one on the access point/base station and the one on the individual computer/PDA etc. (let's call it "the receiver")
2) There is a maximum power allowed under the certified specification.
Given those two things above then you can have situations like the following:
a) you have a WiFi access point that is centrally located and receivers that don't know/care where the base station is. For example you have a WiFi access point on the second floor of a building and it is used by people in the basement and on the fourth floor as well as on the second floor.
b) you have a WiFi access point and receivers that are all on the same floor of a building (or near enough)
c) you have a WiFi access point and receiver that need to communicate over a fixed route (e.g. the LAN in building one connects to the LAN in building two over a WiFi link)
For case a) you need to radiate your signal in every direction including up and down. For case b) it only spreads out in a horizontal plane, so you can use the same amount of energy but get more range. For case c) you can use very directional antenna and get even greater range for the same distance.
And then there are things like, radio transmission takes battery power, so if you don't mind pointing your PDA antenna at the base station, you can use less power to send the signals and extend your battery life.
If you use an FM radio you probably already know that you can get a better (or worse) signal by adjusting the aerial direction and that you can get better reception by using an external aerial etc. but that's reception only
Does this mean I can now legally take the lens off my SLR and stick a beer bottle end in its place?
HP has rigged the BIOS in their notebooks to reject "unapproved" miniPCI wireless cards. They claim the FCC made them do it (it's in their hardware guide IIRC, page 8-1) because the card and antenna have to be approved as a set. So I've been stuck with this Linux-hostile Broadcom card and can't use the Linux-friendly Atheros card I went through a great deal of trouble to hunt down (and is for sale on eBay).
With this rule change, will HP remove this restriction from their BIOS? No, please, stop laughing...
FWIW, it's just HP/Compaq and some IBM notebooks that do this, so HP's excuse seems rather weak to me.