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Tracking Down Wi-Fi Interference?
Nicros writes "Almost every evening, between 8:30 and 10:00, my Wi-Fi just dies. This, in itself, could be explained by a crappy Wi-Fi source or some hardware failure, except that I know both of my neighbors are experiencing the same loss of signal at the same time. While the Wi-Fi is down, the LAN is OK, and anything plugged into Cat5 can access the Internet just fine. One possibility comes to mind — perhaps some other neighbor arrives home and turns on their router from 8:30 to 10:00? And something in their signal is hosing our Wi-Fi? I have tried looking around for software to help identify the source of interference, but either the programs are ridiculously expensive for a home user, or else my card (Intel Link 1000 BGN) isn't supported. (Netstumbler is an example of the latter.) Any suggestions on how I can track this down?"
Let them track it down for you, it's their job. Have your neighbors report the problem also. For 3 reports they'll be there next day with triangulation equipment.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
First thing to try is setting your AP to a different channel.
If that doesn't set you right, get a USB Wifi device that is supported under Linux and fire up Kismet and identify any strong signals nearby.
Once he got a 5 GHz phone all was well.
Long story, short: lots of things use the 2.4 GHz spectrum. It may not have anything to do with WiFi.
An associate of mine reported the same issue. In his case it was a failed security lamp that was trying to come on at sunset and failing; it was only when the ballast gave up after an hour and a half that his wifi -- and his AM radio -- came back. Note that many security lights are sodium arc or mercury vapor arc; not much is as hard on RF in general as a big fat arc.
...put a sign in your front window or building lobby asking if anyone else is having the same problem, or uses electrical equipment only between those times. Make it a friendly note, with smiles, rainbows, and unicorns, so you don't offend anyone or make it look like a witch. As a bonus you get to know your neighbours.
Are you or neighbors cooking with microwaves during that time? They leak like mad. Try using channel 1.
If you are finding your fancy wifi card isn't supported by stumbler and other free channel overlap type tools . . . why not buy a cheap wifi card to use with those apps? You could always drop it back on craigslist/ebay (or even return it to the store claiming it doesn't match your curtains).
I have a similar problem in the morning with my WiFi over a similar time period (1 to 2 hours). I considered that it could be interference from a rogue AP as well and tried shuffling around the channels my AP was broadcasting on but with no luck. Another thought was that there are high-tension power lines near me and perhaps (100% speculation) that higher load in the AM causes some kind of RF interference... Ultimately, I purchased a Netgear WNR3700 which is a dual-band A/B/G/N AP and that sort of solved my problem; my 5Ghz wireless N access in unaffected by the issue so the only PC in the house impacted is my wife's laptop which only can do 2.4Ghz wireless-N
That's the same time I microwave up all my hotpockets for the next day's raiding Ice Crown Citadel...
Are you using Wireless a/b/g or Draft-n?
Are you still able to view broadcasted SSIDs?
What trace information do you have? For example I run netbsd on my wife router and if the wifi interface goes down or stops working I would look in /var/log for trace information.
How close are your neighbors? Do you live on a farm? Or in a block of small apartments? Maybe you have a channel space issue.
http://michaelsmith.id.au
Talk to someone in your local ham radio club and see if they have a member with a spectrum analyzer and a directional antenna. Have them come out to the house and do some direction finding to determine who is transmittin on the WiFi freqeuncies in your neighbourhood.
Be polite. Ask nicely. Buy them pizza and beer to say thank you.
Hams are nice guys and gals and they will probably be happy to help out.
The ARRL website can probably provide a contact for your local ham radio club.
I'd help you buddy, but every night between 8:30 and 10:00pm I'm working on my microwave disruptor beam. If it happens any other time, let me know and I'll be glad to pop over and take a look.
During a remodel of one of my employer's stores, we have trouble with our RF gun (laser scans bar codes, then prints price labels, runs off of 802.11whatever). When I went to troubleshoot it, near as I could figure, the contractors working upstairs has something that was putting out so much RF interference, the gun wouldn't boot because it couldn't read the flash memory soldered to the circuit board. Once the contractors left, it was all back to normal.
You could try to find it with something like this.
http://www.thinkgeek.com/gadgets/electronic/89d1/
inSSIDer
I've been pretty happy using that to help find the best channel for my WAPs in congested areas. If you really believe it might be a neighbor jumping online from 8:30 to 10, that could help. I haven't yet found a card it doesn't work with under windows (assuming you are running windows...)
Happens the same whether you're on channel 1, 6, or 11? (the only b/g channels that don't overlap)
I know in my high-rise apartment, almost everyone is on channel 6, and I wouldn't be surprised if peak usage was mid-evening.
Did you double-check that some rule didn't accidentally get selected, which filters you out (either in the router interface... of you're using software that has scheduling...)
If you're using a radio type that is using the 5Ghz channel, someone's old beastly cordless phone might be affecting it too. If you're using a dual-band radio on your router, try using the other band and see what happens.
Running Wireshark (free) might not tell you what specifically is causing the problem, but you can narrow it down to see if packets are timing out, or getting filtered. Maybe there's traffic you didn't expect to be there? http://www.wireshark.org/download.html
You'll need a spectrum analyzer and an 2.4 GHz antenna. First, I'd confirm that it's interference just observing high noise at that time, then I'd start taking measurements around the area. A high gain directional antenna would be helpful, but you can triangulate just by observing the strength of the noise from several spots around your neighborhood, though, you might have trouble with the signal strength varying too much as you move the cable and connectors around. You might be able to do all the same with just the wireless adapter and some software like kismet.
I haven't failed, I've just found 10,000 ways that don't work -Thomas Edison
This is inexpensive for what your looking for.
http://www.thinkgeek.com/gadgets/electronic/9558/
I used to work several military trade shows at m last job, bringing in all kinds of weird stuff we were doing with wireless tablets and iphones and junk, just to show off what we could do... would stay up till 3am getting everything looking right, would show up 7:30am to make sure the morning of everything was good to go, then boom 8:30am rolled around and everyone fired up there demo hardware and all wireless in the building stopped working, it was ridiculous, happened at three different shows, we kept buying nicer wifi gear each time and failed miserably, until the 4th show that year and a particular company no showed.
The next show they were at and sure enough everything came down not just for us but all the booths in the hall and the hotels wifi, it did not take us very long to get a group together and head over there with the convention staff demanding that they shut everything down until they determine which device was the issue.
They had some very unhappy phb's screaming about ruining there day, but we didn't care, i got my 125 dollar dinner and it was all good.
I will add my 2c and say it is the increased usage of cordless 2.4GHz phones during those hours. Some of the (cheap) units don't behave particularly well with WiFi and I've personally seen just one phone cause a complete outage of all WiFi in a house.
Chances are that one of your neighbours with a teenage daughter bought some cheap but funky looking cordless phone off eBay and uses it every night during your outage window.
Dan. -- So what if it's spelt wrong, nobody's perfect
Give up. The 2.4GHz bands are hopelessly cluttered. Adopt 802.11n before your neighbor does.
Colorless green Cthulhu waits dreaming furiously.
Netstumbler did not support my wifi card but came across InSSIDer which is free, and allowed me to easily see channel usage in the neighbourhood. They also sell USB spectrum analyzers for non wifi interference which is what you may need. http://www.metageek.net/products/inssider
This is exactly the problem we had with our apartment neighbor's teenage daughter. 8:30pm -10:00 pm fits the high school homework phone schedule.
A gift of 5 GHz wireless phones to the neighbors (in exchange for their old phones of course) cleaned up our mutual WiFi problems.
Took the old phones and dumped them into ATT Wireless Store's recycle bin.
Get either the USB stick or one of the 2.4Ghz supported AP's from Ubiquiti. [www.ubnt.com]
The newest firmware supports a Spec analyzer mode - quite good, IMO - and it's not limited to WiFi equipment - anything in the radio spectrum is "seen."
Their wireless bridges in the 5Ghz spectrum using N tech (dual spacial streams) are seriously killer too - if you've got a wireless bridge, or WISP type situation, it's really, really cheap stuff. I'm likely to end up with 2.4 ghz and 5Ghz units just for spec analysis on the cheap. The units then double as AP's / routers / Bridges. (And at around $100 each, they're pretty awesome - Bullet M5, and Nano Station M5's for example.Find a wireless N bridge that will hold links over miles that are that cheap anywhere else!)
For around $100 you could have a nice AP and a spec unit in the same hardware. Antenna, unless built into the unit is a bit more difficult/pricey, but still do-able.
Anyway, I've got a setup using them in a PtMP setup, and though it's not miles, I'm seriously impressed - and the cost factor is simply *insanely* cheap.
http://www.ubnt.com/
-Greg
Typical Microwave ovens operate at up to 1000W @ 2.4Ghz. Typical WiFi operates at 20mW @ 2.4Ghz. Yes, a Microwave oven is shielded in a metal box but 20mW is only 1/50,000th of the power of a microwave so even the slighest noisy leak from the microwave is going to look like some serious noise to the WiFi. At my parents place, the range of the WiFi drops in half whenever the Microwave is on.
If you got an iPhone or a Driod, you can get WiFi-Fo-Fum. Go into your router settings and make sure you're broadcasting your SSID and lock on to it on the smartphone. I've found dead spots in my rowhome (3 stories) where there were just Faraday-like dead spots in my house and one was near my basement PC. Repositioned the antenna and all was back to normal. I also can't walk near the spots when I'm using my mobile or the calls cut off, too.
As a Part 15 device, you have to put up with what other devices are doing.
My first guess would be a non-802.11 device such as a video or audio sender. They can take out many 2.4GHz channels at once, where a microwave oven usually only knocks out a couple.
One workaround is to go to 5GHz -- you're still under Part 15 and susceptible to interference, but there's less of it, a lot more channels, and you can find a 40 MHz channel for 802.11n.
Without something that acts like a spectrum analyzer (such as a real spectrum analyzer -- but some modern access points and other 802.11n devices offer spectrum analysis/FFT capabilities), it's going to be difficult to identify your interference source.
Using a simple reflector such as a parabolic reflector or a corner reflector, you might have a better chance at establishing a direction for your interference source.
Keep an open mind to ANY device which could be turning on and off during the problem times.
I also had this problem and after weeks found it to correspond with the watering schedule for my garden - the water pump was on the other side of the wall to my router and was causing the interference.
Get a radio capable of doing a spectrum analysis a directional antenna (e.g. a yagi or something similar) and a non-directional omni antenna. A connectorized Motorola Canopy would be ideal (but a bit expensive).
Connect the omni first and take a spectrum analysis before and during the interference period to identify the signature of the interfering signal. Once you know what to look for, switch to the directional and use it to find the direction of the signal. Make sure you keep in mind the reception pattern of your antenna when you're doing this, as a Yagi will have 3 lobes, one larger than the other two so make sure that you've zeroed in the largest lobe on the signal.
One thing about the signature: You MAY find that the signal "hops" around. Some SCADA systems use such signals, and it's not uncommon for SCADA systems to have a periodic pattern that repeats every 24 hours.
Oh, and you pretty much have to find this yourself, FCC won't get involved until you can pretty much prove to them that somebody is interfering with you and that they are NOT a licensed user (who likely would have a variance for using higher power than your Part 15 equipment).
Good luck!
"I don't think software should necessarily be free
Try changing the channel in your wireless router. Most set to channel 6 by default.
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Are you absolutely certain it is the wifi? It could be your ISP. You didn't mention whether you were on DSL or Cable. I'm on cable, and I know that whenever my ISP resets my dynamic IP, my router locks up and I have to power cycle it. If it is always happening at the same time, it could be your ISP doing something on a regular schedule.
I doubt it's noisy transmitter because it's unlikely a WIFI radio will interfere with all channels simultaneously. Make sure you try different channels.
If you use linux and your card supports packet injection you can use airodump to capture packets and see who is transmitting the most data. You may also be able to walk around with your laptop and find which direction the signal gets stronger.
Baby monitors. One of the few devices that can completely trash all wi-fi frequencies in an area, not just for 1-20 minutes like a microwave but for years on end. Especially older models which use an analog signal.
I think it is caused by an analog 2.4 ghz phone, and someone chats during that time period. I had one of those phones and found that when I used it it hosed most of the available channels. Replacing the phone solved the problem and doubtless made my neighbors' lives easier. After a move, the same pattern showed up. The solution was a dual-band router.
Summary:
... or else my card (Intel Link 1000 BGN) isn't supported. (Netstumbler is an example ...)
Parent:
Try using a wireless network monitoring program like ... Net Stumbler for Windows.
Yes, I know this is slashdot, and we don't read the articles; but is it too much to ask for you to read the freaking SUMMARY before you reply with a useless load of blather?
Buy a Wi-Spy! This does exactly what you ask with helpful pictures and is what I purchased for this.
http://www.metageek.net/
Your microwave oven operates on the same frequency as Wifi, and 8:30-10:00pm seems like a likely time for it to be running.
:) if you turn it on and your wifi disconnect... bingo, time for a new, less-leaking microwave oven :)
It's also easy to test
Good luck!
I think one of your neighbors is talking to someone at the same time every night using his cordless phone. This could cause the type of interference if you are operating on the same channels and your antennas are positioned such that the RF waves are canceling each other. Try rotating your router 90. Seriously. Or if possible set your router to 5Ghz mode exclusively assuming your neighbor has a 2.4Ghz Phone.
I once had wireless internet from a local ISP. Between myself and the tower was a ham radio operator that evidently likes to walk all over the frequencies. I could never get the douche bag to quit fucking things up on a regular basis.
Steve's Computer Service, Hobbs, NM
Check for any satellites that track overhead at that time.
I remember when they used to open electric garage doors around the neighborhood....
Tried http://www.safelivingtechnologies.ca/rf/Products_RF_Shielding_Paint_HSF54.htm RF Shielding paint? I always wondered if such paint would help. Of course it might kill your cell reception. If so, might be fun to paint your apartment in it before you move or maybe your bosses office when he is away.
At what price learning? At what cost wisdom? The price is a man's peace of mind, and the cost is his life.
Nowadays it might be better and cheaper to go with 1.3 Ghz phones. Uses the TV bands that were freed up. I have one and have wonderfully interference-free calls.
Warning, knife is sharp. Please keep out of children.
Using the 'Spectrum Analyzer' features built in to most APs and wireless clients will only show you other WiFi traffic not noise (almost always true). Also, they are not very portable. The earlier post about asking you local Ham Radio club is a good idea if there is anyone available and many Hams don't have equipment to listen to 2.4 or 5 GHz. You can search on google and other places for a 'usb wifi spectrum analyzer' for less than $50 that plugs in to your laptop. Be careful and read the specs though as some required that you use them in DOS mode. This will let you look at the actual received power level across the whole spectrum. You can walk around with a laptop until you find the noise source. It is still a steep price to pay for a one time fix. If you are the crafty type you can get a ez430-RF2500 target board for $22 from Texas Instruments. You will need to search for a software load that make it a SA but the are many instructions online. If you don't want to roll your own and get a prebuilt solution you can use the Ubiquiti AirView2 for ~$40. This is a very nice tool. You could even split the cost with your neighbors or pool money or request the person with the noisy device foot the bill for finding it.
Metageek has a few products in their Wi-Spy USB Spectrum Analyzer family. The cheapest one (the 2.4i) is $99, and the next model up (2.4x) is $199. It analyzes the entire 2.4GHz spectrum using your laptop and lets you see potential sources of interference. The 2.4x version allows you to use their more advanced software which also has device signatures -- you can overlay signal patterns of various types of devices (microwave, cordless phone, wireless baby monitors, etc.) on top of the signal density graph in order to identify what's causing the interference. I use the DBx version (2.4 + 5GHz) at work, and it's great for helping to find problems.
I had a similar problem but it was affecting ADSL.
It turned out to be a light dimmer switch.
Try wandering around turning off lights...
...Lyall
Might do the trick to figure out where the interference is coming from, if it's another wireless network. I've had it work with a Broadcom card in Windows 7 that wouldn't work with Netstumbler. Might work with yours.
Or you could get your hands on a WRT54G (borrow or cheap on eBay), install Tomato or something like it, and run the site survey tool. Figure out if there's some kind of channel overlap problem.
It protects against more than just aliens you know. Here's an example: http://zapatopi.net/blog/?post=201003245726.the_modern_paranoid_home
Try changing the channel in your wireless router. Most set to channel 6 by default.
Remember, when choosing a channel, only 1, 6, and 11 are non-overlapping with each other - anything in between steps on the channel space of 1 and 6, or 6 and 11. Also, many (but not all) microwaves will impact the channel space between 6 and 11+, generally making 1 a better choice.
Try doing a "survey" using your wireless driver's built-in tools (most Broadcom adapters have some sort of rudimentary tool - Intel should as well). Even just a list of nearest neighbors will help you identify what channels are nearby and at what strengths. Out of 1, 6, or 11, pick something that is within the least occupied space (least number of APs or weakest AP). If your nearest neighbors are using 1 and 6, and another particularly ignorant/rude neighbor is using 3, your only real choice is 11. Now if it's 1, 6, and 9, you're kinda hosed, and you'll have to hope the channel 1 AP is furthest away because the guy using 9 is impacting 1 and 6 (just as the guy using 3 is impacting 1 and 6).
Google search turns up tons of results, but hopefully this paints a reasonable picture:
http://bridgingthelayers.org/channel_overlap.html
Unfortunately your NIC doesn't do 802.11a/n - otherwise I'd suggest looking into a dual-band 802.11n router. Tons of non-overlapping channels to pick from, but the range won't be quite as good (and you'll still have to steer clear of the 5.8ghz cordless phones).
If it's really bad, have your neighbors help pitch in for a WiSpy 2.4x (~$200) which could be used to pin-point the culprit. When you're done, sell it on eBay to recoup most of the cost. Probably cheaper than having a wireless survey team coming "onsite" to validate w/ their pricey Cisco Spectrum Expert device. They'd be able to tell pretty quickly if you're dealing w/ someone who loves their microwave popcorn, a wireless video streaming device, some sort of Zigbee (though those are usually pretty low power compared to Wi-Fi and narrow-band in comparison), frequency hopping device (cordless phone, etc).
$ man woman *
-bash:
Back in the mid 80's I would have been the guy you where looking for. The guy with a 4 element beam antenna that was nearly the size of my house roof. Running a 4K watt bi-linear amplifier on a old but great tube driven DAK radio. I could speak to god on a clear night with that rig. My neighbors however where not that happy hearing my key pinger blare across their tv sets.
Got Code?
WiSpy + walking around = finding your noise
Neato, have you seen any range improvements/differences with 1.3 GHz? I'd heard a few complaints about range with the 5 GHz models. (Nothing from personal experience, I've been landline-less for years.)
Buy a Wi-Spy for $99 from thinkgeek.com
You'll find the problem in minutes.
It could be anything. A couple years ago, we noticed at work that at odd times of the day the entire wireless network would die. It turned out that an engineer had bought himself a set of wireless speakers from Sharper Image and had them hooked up to his work computer. Whenever he fired up his music player, the damned setup blasted noise out across the entire 2.4G spectrum, at max power. It's possible that you are dealing with something similar here, a crappy audio or video device eating the entire spectrum, especially if the times given of 8:30pm to 10:00pm are variable.
And oh yea, that engineer. He was in his own private cubicle and had his wireless speakers inches away from the transmitter. Needless to say, he was informed to remove the speakers and we established a policy that required all wireless devices be approved by IT.
If you use DD-WRT which allows you to fine tune wi-fi router, and set "Wireless Network Mode" to N, and "Channel Width" from default 20 Mhz to 40 Mhz, then in Advanced Settings "TX Power" change from default 71 mW to max 251 mW, then you neighbour with pretty much standart WIFI router will have to start usin good ol RJ45. arnie said.
a tuned antenna, such as those 22'ish element beams for the band you're having problems with, attached to a spectrum analyzer or any number of other useful RF gear, and just wave it around and see where it's coming from. would take you all of about 20 minutes to nail down the house its coming from.
The antenna's cheap. The analyzer, well, find a friendly ham radio operator in your area that's sympathetic to dealing with interference and borrow it or have them give you a hand.
Or on the very cheap you could get one of those crummy little "Wifi hotspot detectors" that is only an RF meter. (does not for example, give ssids or allow you to select only open networks - you want one of the $15 ones with four lights on it for strength) and follow that around. They're directional and there are other tricks you can use to get a better bearing from them.
I used to play cat n mouse / fox hunt a lot, and trust me, a directional antenna is definitely NOT required to track them down. Sure can make the job quicker tho.
I work for the Department of Redundancy Department.
or make it look like a witch HUNT. Doh.
What you need is a Wi-Spy, available from http://www.metageek.net/ These devices scan the RF for what is active. It helps detect 802.11 and other RF interference sources, and may help you find a better channel to use. Note, I am not affiliated with Metageek, other than being a happy customer. I support wireless networks as part of my job, and I can tell you that spectrum analysis is what you need.
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My WIFI dies when the microwave is switched on.
8:30 - 10:00 could also be a baby monitor.
I'll never make that mistake again, reading the experts' opinions. - Feynman
I have the original WiSpy model, from when they first hit the market, and I still use it extensively.
It's been insanely useful in tracing the problems, just put it on a laptop, with a long USB extension cable, and wander around. I will admit that I've only used it on Linux, as I don't have any Windows around, but it's been perfectly suited to my needs.
A friend of mine was having a similar interference problem, during a subset of hours, and I traced it to one of the neighbours that would prepared dinner while using a set of wireless headphones.
ICQ# : 30269588
"I used to be an idealist, but I got mugged by reality."
You need to find out where it's coming from. If you can't get hold of a directional scanner or similar fancy gear, just sabotage the neighbors' electricity supplies one by one.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
They're bad for WiFi and that's about the right time.
Mama has to watch the morning show in Bombay using one of these? http://www.smarthome.com/7656L/Leapfrog-Wireless-Audio-Video-Transmitter-and-Receiver-System-LF-30S/p.aspx
Havn't done much testing. Covers my apartment with no worries, but thats not saying too much.
Warning, knife is sharp. Please keep out of children.
2.4GHz is a "junk band" i.e your equipment is unlicensed. The disadvantage of being an unlicensed user is that you must accept any interference encountered.
If you do find the source, what are you going to do about it?
There are various LICENSED services in this band which are entitled to be there. Hams for instance are allowed 1500 Watt PEP on 2.4GHz.
see http://en.wikipedia.org/wiki/High-speed_multimedia_radio
I actually had the opposite problem - back in 2004 I bought a 5GHz phone system expressly to avoid interfering with my 802.11g wireless. When I went to 802.11n a few years later, I set the base station to 5GHz to avoid interference from all the other 2.5GHz wireless around...and saw the signal go to hell whenever the phone rang.
Not long after that I ditched the landline for good.
Google xirrus wifi monitor. Is a free wifi signal monitor.
The DECT phones that finally made it to the US use 1.9 GHz, and they seem to be very common in stores now, and fairly cheap.
Climate Progress - Hell and High Water
The last line is "kenya believe it".
If you're going to post a meme at least get it right, doofus.
Buy a mikrotik router. I have a RB433UAH and a R52N card (I think), you can get views like this:
http://wiki.mikrotik.com/wiki/Manual:Spectrum_analyzer
It has various other tools to do AP scans etc and could perhaps to be used to triangulate the source with a directional antenna.
I would assume it's lower.
Less energy spent on the frequency means more spent on the range. Lower frequencies also tend to penetrate obstacles "better"
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
+1 - we were given a baby monitor that transmits live video and source temperature. It destroys our WiFi capability - but only within 20 metres or so.
Actually, you're ignorant (though fortunately not rude), not necessarily the neighbor on 3.
Depending on the network built up around him before he moved in, it's quite possible that channel 3 (ducking the 11 across the hall, and interfering with the 1 and 6 on either side of him, but at least down a few dB) is a better setup for all than stomping directly on top of any one of them.
The best solution would be 1/6/11, but with the entire world reassigned for optimum spacing whenever a new AP comes up (Actually, pathological layouts probably exist to make a 1/4/7/11 plan better, but by far most layouts are adequately served with 1/6/11...), but this is infeasible. So sometimes, having control over only your own AP, channel 3/4 or 8/9 is really the best you can do.
And BTW, WiSpy's too expensive. Get a Ubiquiti AirView -- same thing for ~$60 IIRC.
Make it a friendly note, with smiles, rainbows, and unicorns, so you don't offend anyone or make it look like a witch. As a bonus you get to know your neighbours.
wow. you have not met my neighbors.
Between 8.30 and 10 in the evening seems like somewhat who is watching TV with those TV repeater to get the cable signal in another room. Many of them use the unregulated spectrum. If that's the case the source must be fairly close.
WiSpy (even just the "cheap" version 2.4i) may turn out useful especially if the issue is so repeatable (so that you don't have to leave the analyzer logging for days).
While router channel conflict is a common problem in denser areas, I found out that my variable speed central heater was causing power and radio interference with my internet connection when it turned on. The heater manufacturer had a kit to fix it though. I only noticed the interference source while using a portable AM radio and listening between the radio stations.
Fox and CNN supply different data. A Wi-Fi channel carries the same data. A difference that makes no difference.
Maybe it's possible a ham radio op lives near you and he is most active at this time. If he is putting out enough power he could overload the "front end" of the radio receiver in your device or router/ap and thus attenuate quality signals. Depends greatly on frequency, power, modulation type and antenna design but maybe you are getting the perfect storm? Also- here is an awesome link on how to build a $10 Radio Direction Finder. http://theleggios.net/wb2hol/projects/rdf/tape_bm.htm
Either you or your neighbor are cooking popcorn / nachos / tv dinners in your microwave every night, or your other neighbor with the 2.4GHz tv repeater is watching scrubs. You should immediately break into your neighbors' houses and smash their appliances with a bat.
Not at all. Changing channels is a low work method to solve the problem which will take little time. Since it may very well fix it, it is an efficient first thing to do. Who needs to know about interference on an unused channel? Additionally they may provide information. For example, If all channels are blocked then it is not likely to be another Wi-FI issue unless something is majorly broken (to the point of not functioning). If the quick, cheap and easy fail then you assign resources to the problem.
Here are the devices to look for:
Microwave ovens
Cordless phones (this happened at my home - moving cordless base away from router solved the problem)
Surveillance cams (like baby watch monitors, etc.)
Domestic TV repeaters
Ham radio equipment (if the interference is on a 2.4 GHz WiFi device: part of the WiFI band is shared with them)
As somebody has already suggested, changing the channel of your access point might help to solve the problem. Good luck...
In my life I have gone from broke to wealthy and back several times. Living in a social democracy has allowed me to take many risks. Aside that, circumstances change. They always do.
In fact not even with the trash. Soup and a tube work better and don't get players killed.
It routes MILFs to his bedroom so he can root them. ["root" pronounced the same a "route" is Aussie for fornication] On the other hand, since route and root are homonyms in English (not American) a "wife router" would be her husband...
Nicros, someone very close to where you live has a Wireless TV transmitter.
Check the voltage in the AC electricity supply network with a digital voltmeter during these hours.
If it drops down during these hours, then buy a stabilizer. Usually when people get how they switch on various electricity consuming devices. And if a transformer in your neighborhood has not enough capacity the voltage or frequency of AC may drop down.
It may manifest itself especially when it is hoot or cold outside, because heating and air-conditioning takes a lot of power.
Saw this link: http://boards.ie/vbulletin/showthread.php?s=adf37f5bc9893161b909b2f8ed3a15e7&t=2055944813
on this story: http://forums.theregister.co.uk/forum/2/2010/06/28/ofcom_pln/
Which seems relevant to you - maybe a neighbour turns on something noisy.
Sam
blog.sam.liddicott.com
inSSIDer lets you visualize the strength of all the surrounding wifi networks, and if they overlap or not. It's free.
perhaps at 8:30 your neighbors are settling in to an evening movies with a big batch of microwave popcorn... or dinner of microwave casseroles... 2.4ghz cordless phones are nasty also... make sure you dont have any such cordless phones...
if they are microwaving, prolly wont help to change channels, but otherwise it often helps to force your router and laptop to a wifi channel...
Just an idea...
reflash your stuff to use euro/jspec frequencies.
CH11-14 are pretty clear mostly.
Capitan Ventosa (Captain Plunger) is an Italian hero with a plunger on his head.
With his "Ventosa Radio Team" discovers radio interferences with an antenna attached to a spectrum analyzer.
If you have an Android phone, you can download a free application called WiFi Analyzer by Kevin Yuan which scans signal strength and can identify possibly interfering networks, pretty much like NetStumbler but in a more convenient package. If you are patient enough then you can map out signal strengths in various locations when you have GOOD reception, and then compare them to what happens when you have BAD reception and see where the interference is worse.. if it's a rival WiFi network then it should be even easier! But as others say.. the source of interference could be one of so many things in the 2.4 GHz band including DECT phones, baby monitors, microwaves or even just plain old fault equipment
Never email donotemail@WeAreSpammers.com
Boeing and Mitre have both trashed my wireless signals to Part 15 devices. And they are primary or secondary on the bands in use. WiFi is an unlicensed interloper of limited power. Confronted by even the sidebands of some transmitters operating in a licensed and legal mode there is no hope. Except. Faraday shields keep all the signal goodness inside in as well as keep the bad juju out. The moral of this story is when you walk through a metal door with metallic gaskets ask your friendly native guide what you're walking through... And I swear some joker at Boeing scans through the 305MHz car alarm unlock sequences when his equipment is otherwise idle. My car unlocks itself about once a month. I'm not the only one in the area hat it happens too either. And remember that like most Part 15 devices the receiver is deaf. A good quality 2.4 or 5GHz receiver will see a pretty solid noise floor from all the WiFi for 1000's of yards or more in urban settings.
- Tjp
I am in wallow with my inner money grubbing capitalistic pig. ... Oink!
For basic, "free" analysis you could try the Wifi Analyzer app on the Android market (perhaps one of your friends has an Android phone if you don't?) http://www.androidzoom.com/android_applications/tools/wifi-analyzer_bgn.html
Try inSSIDer which also can show you some of the non-broadcasting networks.
But nevertheless the true tool would be a spectrum analyzer, Metageek sells some cheap ones.
And think about moving to 5Ghz.
Wireless intereference is not something new, and 2.4Ghz aint just big enough, especially not in apartments complexes, and equipment broadcasting at full power.
Which doesn't transmit unless there's sound detected, eg. crying.
I'm well aware of useful tools like kismet, Inssider and Wi-Spy, but what if the former can't help, and the latter seems too expensive? surely there is a team like the FCC you can call in the UK if a streets wifi is all interrupted at the same time for no clear reason.
If you and your neighbors all have routers on the same channel then you could be interfering with each others signals all the time and it is just made worse during high use times. I think the default for most routers is channel 9 or 11. Try using vista stumbler it works with win vista and 7. Look at all the network that are available and see what channels they are on. You want to pick a channel that is not occupied or if the are all occupied the ones with the weakest signal.
He screwed up more than just the last line.
I had this problem at one time. Used the free version of NetSurveyor. Found out which channels were being used and manually set the router to a different one.
http://www.nutsaboutnets.com/performance-wifi/products/netsurveyor-network-discovery.htm
Just a suggestion: It might be a treadmill exercise machine. I have one which completely knocked out wifi and ADSL until I isolated it with a expensive choke on the mains lead. Ask your neighbours if they use one between the hours you gave.
libguestfs - tools for accessing and modifying virtual machine disk images
Growing up a friend of mine had a CB base station and a Ham radio, not satisfied with the range on his CB Base station he added boosters to his system. Any time he fired up his Base station to full power, TV's for a block or so went out everytime he key his mic. Look around and see if you see any radio antenna's around the neighborhood. Could be an overpowered CB or Ham Radio operator that gets on at that time every night.
There's these cheap TV signal extenders you can get that work in the unregulated 2.4Ghz range. I'm betting it's something like that.
Someone is using a 2.4 ghz video sender. It wipes out all the the 2.4 Ghz band. Get your own sender system and figure out what they like to watch. You may consider sending your own content as well.
You do realise you're posting on slashdot?
To have a right to do a thing is not at all the same as to be right in doing it
Use your body to block the source of either the signal or the noise. Hold your WiFi radio (either your laptop or your access point) in front of you and slowly rotate while you watch the signal or noise level. When it drops, the source is probably behind you. Walk down the street if necessary and do it again to triangulate the signal.
Even a microwave oven, but it's weird it's lasting exactly 2 hours. Maybe some of your neighbours has some household "experiment" running (fusion reactor anyone?) Arrange this with your neighbours: each one of you tries channel 1, 6 and 12, just to check that it affects all frequencies or just one. Another thing you could try: get a directional antenna to try to find the source of the interference (if you point it towards the interference source you should get few or none aps when passively scanning -with kismet for example). Taking into account you have like 2 hours, you can triangulate an approximate location.
But I have ~30k of computer gear in use in this house. Bought when I could afford it. That was before a separation. So, you telling me I should sell my gear and use the library? That is a bit offensive. Particularly as due to ill health I can't climb the hill to it anymore. "You are old, father William the young man said...."
I'd like to be. Bt I was in IT and the young never believe the old can be wise about anything. Yeah, I would love a job again.
1. Get wifi-detector gadget with signal strength indicator.
2. Ask all neighbours to turn off all their wifi, microwaves, remote controlled cars etc.
3. Place said gadget at bottom of pringles can.
4. Stand on roof and do 360 degree sweep. Note signal strengths.
5. Walk to end of block, repeat sweep, noting signal strengths.
6. Triangulate.
7. Use diplomacy, US style. send the marines as first resort.
and source temperature
I know this is probably for detecting a fever. But I just wanted to point out that it's also good for detecting dead babies.
figuring out that every time someone ran the microwave in the kitchen the WiFi video camera stopped sending and didn't recover.
If you is on a modern Windows, InSSIDer should at least allow you to poke around your wifi neighborhood:
http://www.metageek.net/products/inssider
(Sorry if someone already posted this, I didn't read the whole thread, and yes, that 'is' up there are on purpose)
Nerd rage is the funniest rage.
What I had to do... "sudo iwlist eth1 scan" from the terminal. After you provide password, you get a listing of all the available wifi routers in range. One will be yours, check the channel it is on; compare it to all the other routers that show up in the list. Make sure that you are not sharing a channel with any of them. (I.E.: change the channel your router is on.) This is what solved my issue.
With my issue, both my neighbor and I were on channel 6, and I was still being interfered with. Once I went to 7 it was fine.
... not holding the NIC in your left hand?
WHY does the FCC allow these things!
.
.
.
I mean, what are babies good for anyway?
Not sure where you are experiencing your problem: at work or at home?In my case, my son's XBOX USB WiFI dongle was periodically trashing my home WiFi. Finally gave up, ran a wire and poof WiFi problem is now gone. Any consoles on your Wifi network active between 8and 10?
There is an excellent article about resolving WiFi problems like this at http://www.smallnetbuilder.com/wireless/wireless-howto/31190-when-wireless-lans-collide-how-to-beat-the-wireless-crowd
It turned out it was my alien neighbors communicating with their mother ship circling Uranus.
I bought a new amp that supported wireless surround sound speakers and after a while figured out that they were killing my WiFi. The manufactures documentation didn't specify the band (maybe in the fine print) and the vendor was hard put to come up with what WiFi channel to use. After two years the vendor still has nothing about this on the web site and I have to turn the amp off to use WiFi.
Nate
but how can 1.3ghz be better than 5ghz? surely more ghz is better? like a six year old pentium 4 @3.8 ghz is much better than a new core i5 @ 2.2ghz. its a shame you can't buy them anymore.
Wealth is the gift that keeps on giving.
I don't know about wifi, but I'm having problems with my garage door opener. Most of the time I can open the door from my car from the street at the end of a long driveway, but sometimes I can't even get it to work with the car right in front of the frag'n door! I have no idea what frequency Sears uses for their remote controls but it's probably in the 900mhz or 2400mhz bands.
A few years ago I purchased a simple sound system, (actually I believe I got it for free when I purchased something else like a TV), and it was a Panasonic. It didn't come with rear speakers, but they had these wireless rear speakers, so I bought them a few months afterward. These were 2.4 ghz as well, but they interfered with the wireless upstairs something horrible. We would sit down to watch TV (you know, like prime time, 8pm-10pm) and turn on the sound system, and it would kill our wifi access instantly. The worse part about the system is that it scanned channels automatically and picked one which wasn't being used. I live in a suburban area, and you can see 10-20 SSIDs from my house. Needless to say there are not many channel "holes". Perhaps one of your neighbors has a similar setup? I've since bought a new sound system complete with wired rear speakers.
FLR
I had a similar issue at an old apartment. I tracked it down to my 2.4GHz phone - whenever it would ring or we would talk on it, it would knock our 802.11abg router signal out. They both operate at 2.4GHz, causing the interference. I replaced my phone with a 5.8GHz phone, and that took some of it away. Our neighbors also had a 2.4GHz phone, and whenever they would get on the same thing would happen. My final solution was to move :) I've had few issues since I moved to a 5.8GHz phone and 802.11n router.
This is my Sig.
Could be a cordless phone....May be even FCC certified ;)
I have a phone at home (Panasonic, 2.4GHz) that blocks _completely_ my WiFi access point. Tried with two different routers, Linksys WRT54G and Apple Time Capsule. Initiate a call and voila - no WiFi access. Got rid of it and switched to Time Capsule with 2 frequency ranges, this helps a lot (especially if you have more than a dozen of other 802.11g APs around :) ).
Chances to find the source of interference are quite low and, possibly, getting a 5GHz router is easy, they are not that expensive. One thing you can do, if you are sure about 8:30-10 is to use any software that scans WiFi networks around (Kismet?) to find the new network that appears around 8:30. If you can identify the network, you can try to track down the source - walk around with the laptop, measure signal strength, try to guess the direction.
Depending on how good you are with your neighbors, you can also try to drop them a polite note asking to help to identify the wireless device causing troubles for others. Offering free help to reconfigure it :) Assuming the owner does not use this device on purpose :)
inSSIDer will scan the freq's just like netstumbler but works with your existing wifi driver and stack. it will work with and card on XP, VIsta, or 7. as for netstumbler you don't mention your OS it only works on XP. Second, the FCC will investigate if you phrase your complaint properly. use the terms Pirate Broadcast, and or terrorist transmission. don't expect them to solve it overnight it may take a few days or weeks for them to even show up. Third, consider switching to 802.11n 5Ghz if the issue is specific to the 2.4Ghz range then using 5Ghz will evade the problem.
there are 10 types of people in this world, those who read binary and those who don't. which are you!
A coworker of mine has a similar issue with her cell phone at her house. When she gets within 2 blocks of her home her phone loses its signal, and she has confirmed with her neighbors that also have the same carrier that they have the same problem. She recently got a new phone thinking that it was a problem with the phone, but the problem continues. Other people with the same carrier can come over and their phones on the same network work with a full signal, but everyone that lives there continues to have trouble. She and her neighbors have called the carrier, done the tower update codes and everything else that they make you do and the carrier continues to claim that there is no problem and they have to live with it.
We live on the Ohio River and our 2.4GHz WiFi (all bands) was wiped out periodically just about every day for 10-15 minutes at a time. Neighbors all reported this, as well. I bought a WiSpy and patiently waited for a blackout to occur, then correlated them all to barge traffic on the river. Only then did I notice the big rotating antennae on the tugs. It is only a small leap of faith to determine that our problem is bleed-over from similar-spectrum Marine-band radar into the unlicensed 2.4GHz spectrum. Could have changed to 5GHz (where my phones operate unhindered) or coax-based MoCA, but I decided to try HomePlug-spec'd devices, which use AC house wiring to get encrypted 100Mbps throughput. My Linksys Powerline boxes can be plugged in wherever they are needed, have worked flawlessly, and I have a spare for when people come over to work with me. Still use WiFi around the place for maximum portability, but not for production-mode stuff.
If you suspect the problem is coming from another Wi-Fi signal, you can download and install the app "WiFi Analyzer" to turn your phone into a handy little tool for seeing just how many networks are in range and the relative signal strength of each one. You can even use it to pick the best channel for avoiding interference, and the app is free.
So do the obvious and shoot at it already. Instant results guaranteed.
Who is General Failure and why is he reading my hard disk?
i have heard a similar anecdote onetime and it was some people starting up some heavy duty machinery and/or doing arc welding or metal grinding or something like that. i vaguely remember it had something possibly to do with 3-phase power, and it was due to some lazy fucks being fucking lazy. starting some generator or something to do the above work and it was causing the interference or something.
fucking slashdot requires i must wait more than 8 minutes before posts?
get fucked.
lashdot requires you to wait between each successful posting of a comment to allow everyone a fair chance at posting a comment.
It's been 8 minutes since you last successfully posted a comment.
and that was on a completely fucking different thread too, for fucks sake.
fucking retarded system for retards.
It's been 9 minutes since you last successfully posted a comment
It's been 10 minutes since you last successfully posted a comment
You can get a $40 2.4 GHZ Spectrum Analyser from here: http://www.microcom.us/airview2.html
There are also others with external antennas: http://www.microcom.us/browse-by-brand--ubiquiti-networks.html
Don't forget those newer DECT 6.0 phones. They're cheap and they operate on the 1.9Ghz band. IIRC, that spectrum space was set aside for phones only because of this exact problem.
I had a sucky sig.
Yeah, the 6.0 is misleading, it was called DECT 6.0 in the US for marketing reasons. The 6.0 means nothing other than being a higher number than 5.8.
Even though 1.9 is far better than 2.4 and 5.8 (2.4 is a noisy band, higher frequencies don't penetrate obstacles as well.)
retrorocket.o not found, launch anyway?
Odd, there are actually two subbands within the 5 GHz band, and phones are in a different one than wifi.
Phones are usually around 5.8 GHz, wifi is usually a bit lower IIRC.
retrorocket.o not found, launch anyway?
Exactly what I was thinking!
or an 800 MHz phone. All my wireless phones a re 800MHz to avoid WiFi interference, and they work as well as any other wireless phone.
http://www.smallnetbuilder.com/wireless/wireless-howto/31190-when-wireless-lans-collide-how-to-beat-the-wireless-crowd - The guy is no slouch. maybe not the most technical article I ever read, but it should help you.
There is a Slash-Dot article from last year about ... the affected parties are almost certainly seeing interference from non-Wi-Fi devices such as microwave ovens, Audio Video senders, security cameras or baby monitors."
unlicensed 2.4GHz baby-monitors in urban areas and
interference with Wi-Fi devices.
"Our research suggests that
The Slash-Dot link is here:
http://hardware.slashdot.org/article.pl?sid=09/05/11/1335208
Find a friend who uses a mac laptop to come over and download a program called KisMAC, its a program that uses your wifi card in passive mode and collects packets to analyze for retrieving router keys. You might also be able to find a similarly functional computer for PCs with specific network cards, it seems like you already tried that and had difficulty so thats why i suggest kismac. Start it up at 5 or 6 while your internet is still up and running. Periodically look at it and see what routers seem to be getting traffic, you'll be able to tell by how quickly the number of packets collected goes up. then, if on this particular day your wifi network goes down, pay close attention to any network transferring lots of packets especially if it hadn't been very active before. If its not on the list or it doesn't work well its most likely not interference caused by another router and you'll probably need some more sophisticated equipment to track it down.
I find smiles, rainbows and unicorns incredibly offensive, you insensitive clod.
At least you didn't recommend comic sans.
Wouldn't it be better for detecting living babies? The dead ones would approach room temp and become "invisible" in the IR spectrum. The live ones should stand out like a sore thumb.
That's a bit much. Why not just change the channel/set it to Auto, and maybe set a password? They'll never look back at it anyways.
"When information is power, privacy is freedom" - Jah-Wren Ryel
get Google to look into your wifi for you? I'm sure they'd be happy to.
BWAHAHA
You do realise you're posting on slashdot?
Not everyone knows their mom as well as they should.
Track your TV Shows with your iPhone - FREE
We run our baby monitor all the time (and I was sure to get a 900MHz one for distance, which it turns out isn't all that great, maybe 50 feet). But there are a lot of them at 2.4GHz.
Its cause everyone is using their microwave ovens in the morning to nuke their breakfast. those tend to wipe out wifi as the microwave is about 10,000x stronger, and even with the shielding enough leaks out to drown out wifi....
That is not correct for North America. The 700MHz band is what was freed up, UHF channels 52-69. Channel 69 was at 800 MHz. The highest channel ever allocated was 83, at 885MHz (rescinded sometime in the 80s). There was no 1.3 GHz broadcast TV channel in the US.
-molo
Using your sig line to advertise for friends is lame.
I didn't set aside $5. I set aside $330,000. But settlements can do horrible things. I kept my business but no operating capital. It will me take some years to recover. Since I do not use credit things are sometimes tight. What he is saying does not account for the vagaries of fortune which he will doubtless realise when he is older.
No, I think they're marketed for SIDS prevention, so your dead babies is right on.
Fever would be pretty hard to detect without being invasive if you think about it. If a room was cold a feverish baby could have skin that was more or less cool to the touch.
"ONLY" 20 metres. Nice mansion you must be living in.
If your microwave is wrecking your Wi-Fi connection, don't grumble about it. Get a newer microwave oven.
This problem is not limited to "old" equipment.
My less-than-two-years-old top-of-the-line Panasonic microwave stops all wireless communications in the house when operating.
Live Long and Prosper - Thanks Leonard. You are missed.
http://www.thinkgeek.com/gadgets/electronic/c240/
You know, it's getting really crowded out there. And we're not just talking about that ever-increasing ring of space debris that is orbiting the earth. All those defunct satellites, explosion fragments and paint flakes are really junking up the place. No, our immediate concern is the ever-increasing use of the 2.4 GHz "junk band" and how it can cause interference problems with your equipment. So, if you want to analyze the 2.4 GHz band to see all that junk, we have the perfect device.
Insert alternative description here
The new Wi-Spy 2.4i packs a lot of value into a compact package with extra-fine resolution and a super-low noise floor, not seen on other entry-level tools. Plus, Chanalyzer Lite, Wi-Spy 2.4i’s software, offers a great assortment of features that help you get to the bottom of interference issues quickly and easily. And to top it off, it now has a 3-D view and Mac support.
What does Wi-Spy 2.4i do?
* Tracks all radio activity from Wi-Fi, Cordless Phones, Microwave ovens, Zigbee, Bluetooth, or any other 2.4 GHz device.
* Graphically shows which channels to use and which ones to avoid.
What's unique about Wi-Spy 2.4i?
* Best resolution in the sub-$100 price range.
* Bundled with the latest software, Chanalyzer Lite, the definitive answer to spectrum analysis on a budget.
* Compatible with both PC and Mac!
How can the Wi-Spy 2.4i help me?
* Resolve wireless issues quickly and easily.
* Know the best channel for your WLAN.
* Track access points and their channel usage with real-time radio data.
* Keep on top of intermittent interference issues.
System Requirements:
* Windows XP or newer with .Net 2.0 or Mac OSX 10.5
* USB 1.1 or 2.0
Wi-Spy only works for Windows/Mac. Not Linux. Sigh.
Decomposition generates a lot of heat...
Maybe be peaceful solution is better after all.
Now I regret yelling "get off my lawn" at them all these years.
Fair enough. But if a parent hasn't checked on their kid in enough time for decomp to generate enough heat to notice, I'd contend that the parent has other issues.
My old 900mhz phone works great. I never get interference from house wiring, or wifi and it has great penetration through walls. Works anywhere on my property. Do they still even make 900mhz phones anymore?
Ship radar is one possibility. So is airplane radar. At certain points during ascent or descent, planes can point right at housing areas with their radar. That is especially true when they are not allowed to circle. I lived right in line with a major airport for a while and when the prevailing winds were blowing, ascents would aim right at my place for a few minutes. During that time, the plane's forward lights would shine (weakly at that distance) into the window and the radar would really disturb FM signals on the radio. Then the plane would veer off and the radio would go back to normal until the wake cleared and the next plane could take off. However, all that is too short to match the problem described in the original post where wi-fi is out for hours.
Beta is broken and the link to classic doesn't work. Stop wasting our time or there won't be anybody left here.
Previously at work i used pretty expensive equipment to analyze the wifi spectrum. Nowadays the only thing i need is my Nexus One and the Wifi Analyzer application. While its very simple and not at all very fancy i have no problem isolating and identifying sources of interference.
Have you tried a couple of other channels? If that dont help its probably not another wifi thats the source of interference. A simple triangulation with Wifi Analyzer and the channel rating stuff should make it easy to spot exactly where the interference originate. Unless its really strong, then you have to extend your triangulation area a bit.
HTTP/1.1 400
OK, it's a little more expensive and doesn't have great range through walls plus most Wireless N equipment can utilize the 5GHz band. I can usually discover 20+ access points from inside my apartment all running on various channels in the 2.4GHz band, my wireless network is the only one running at 5GHz, and I've never had a dropout while using it. I no longer get interference from cordless phones, microwaves, etc.
That would be solar flares, son.
"You killed my yogurt!" --Fred Fredburger
lol - I love /. The only place where a dead babies joke can be regarded as funny! Awesome
If you can read this... 01110101 01110010 00100000 01100001 00100000 01100111 01100101 01100101 01101011
Grab a copy of Backtrack-4, and a netbook/laptop, fire up airmon, set it to radio monitoring mode, wander around and see what it coughs up.
http://www.aircrack-ng.org/doku.php?id=airmon-ng
and
http://www.backtrack-linux.org/
You get a pretty graph and everything.
Some night, drive around your neighborhood at 9:00 to see if there's any kind of law enforcement speed trap in the area. The radar gun could play havoc with nearby wireless.
Just don't drive around too fast!
Well, I *do* have neighbors, but they're over 300 yards away.
Every night at 10:15-10:45, my wifi craps out and needs to be restarted. It's gotten to the point that I've got it on an x10 controller that I can use with a remote.
It's the *only* thing in the house using x10. We don't have a microwave. Noone is on the phone. The TV has been on for hours at that point.
I'm going to try changing channels, but still, it's quite weird. Restarting the wifi takes care of it, I don't have to restart the cable modem. It's a horrible d-link device (dir-628) that I would never buy again.
Way to throw out something that works just fine (if for someone else). Let's burn through all of the resources on this planet as quickly and as wastefully as possible! (And, no, "recycling" is significantly wasteful too.)
But it takes a while for the body temp to jump up for decomposition after the initial temp dip back to room temperature. Probably days.
Sounds ridiculous I am sure, but there was a fairly elaborate wireless network setup in a little town in the middle of nowhere. Everything worked fine with normal problems here and there for 2 1/2 years. Until one day, all wireless signal went down from 3-5 p.m. Since the day it started, it has happened everyday since. I was never able to fully understand the problem, but several technicians from the Utility Commission whom I believe, said they finally found out that a power company was transmitting data through a point to point wireless connection to another facility a couple of miles a way. They said that they were sure this was the problem. Just sounds familiar to me.
Caveat: IBM customer engineer involved -> my tech-ish brother -> me. Take with requisite amount of salt.
Was shortly after the "foreign attachments" decision in an IBM antitrust case, which required IBM to post specs and allow other companies to build and plug in peripherals. During that period a bunch of multivendor projects got started - and many were the rounds of finger-pointing when it came time to integrate the products of a half-dozen or so vendors into a delivered system. This was one of 'em.
The system was being integrated at the install site - a building at an airport. Every piece had worked just fine in the vendors' labs. Nothing played well at all on the final site. Was a madhouse of vendor engineers trying to get things to play together.
At one point one of the engineers got sufficiently bugged by a flickering fluorescent light that he decided to do something about it. He got a ladder and turned off the lights preparatory to doing the fix - but the tube kept flickering. "Hey, guys. Look at this!"
Turned out the airport's search radar was right next door to this wooden building. Anyone familiar with transistor circuits and the number of volts-per-inch of signal strength needed to light an unpowered fluorescent lamp knows what that means.
They paneled the wall with aluminum. Everything started working. All shook hands and went home.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
You know that big old ass microphone Larry King uses at CNN? That's it.
Nikola Tesla designed it for Larry King personally.
And complaints from the neighbours.
(Actually, pathological layouts probably exist to make a 1/4/7/11 plan better, but by far most layouts are adequately served with 1/6/11...), but this is infeasible. So sometimes, having control over only your own AP, channel 3/4 or 8/9 is really the best you can do.
1/4/7/11 still have some fringe overlap for edge sub-channels (especially between 1 and 4), don't expect full speed w/ lots of neighbors.
Using 3/4 or 8/9 may help your problem (or at least afford you some lower data rates), but in an apartment complex or other high-density independent deployment, it only contributes to the overall problem, making channel dodging that much more difficult.
This argument is akin to an approx 71.5 foot (mhz) wide freeway with with 3 twenty-five foot wide lanes (1/6/11@22mhz wide + 2.75mhz spacing between 1/6 and 6/11). By design, you're driving your hypothetically 22 ft wide car down the center of the lane. There's up to 1.4 ft on each side in the center lane between you and the lane edge.
You can try to drive between lanes, but you're still going to "interfere" with traffic nearby. Condensing the lanes into four now creates significant overlap between traffic (approx 10-25%).
Now in reality, an OFDM (802.11a/g) wireless signal is made up of 48 sub-channels equally spaced across its 22mhz "channel". Instead of completely wiping out your signal, some of your sub-channels would be interference-prone, effectively reducing your data-rate. So, you can choose channels besides 1/6/11 (or 1,5,9,13 in the EU), but you must understand the consequences to yourself and your neighbors.
Or just go 802.11a/n on 5ghz and call it a day. 2.4gz is becoming far too crowded in highly dense deployments anyway.
$ man woman *
-bash:
Try 1 or 11 instead. 7 is only 5mhz offset from 6. You're still sharing 77% of the spectrum with your neighbor and killing about 10% of anyone nearby who may be trying to use channel 11.
$ man woman *
-bash:
Wi-Spy's included software only works in Windows/Mac, but there are 3rd party open source tools like Spectool-GTK that do work in Linux.
$ man woman *
-bash:
If I read the original story correctly, this would be a complaint involving multiple users over a definite geographical area (neighborhood), about strong blanket (not intermittent) interference for several hours. Chances are that this is leaking in broad spectrum, not just the 2.4 region. But perhaps I did not read the story correctly. As I recall, I had not yet finished my first pot of coffee.
Will
With a couple hundred and a quick google search you could get yourself on 5ghz 802.11n and forget the whole problem.
We've got a WiSpy DBX, and 5Ghz is remarkably quiet anywhere I've checked. Choose a channel > 100 to avoid conflicting with 802.11a 5Ghz.
Satellites don't hang around. They appear strongly and disappear quickly. I've "seen" them. Their bandwidth is, of course, limited and outside the three bands used for 5Ghz 802.11n.
All my neighbors use 2.4Ghz ch 6. Ch11 is all mine.
When I was in college, I lived with several other people in a crappy, partially furnished old house. The microwave that came with the house must have been terribly shielded, because even being on the opposite side of the house from both me and the wireless router, it always knocked me offline.
Fortunately, the house's second story was added haphazardly, and through some miracle the faulty wiring didn't kill us. Half of the outlets in my room were on the same circuit as the kitchen, half were on a separate circuit.
It took me about a month of living there before I figured out the solution - buying a toaster oven from the thrift store and hiding it under my desk on an extension cord to the outlets on the other side of the room. Every time I had an important raid going on, or some other dire need for the internet, I popped on the toaster oven. The outlet would short out before it tripped my internet connection.
Passive aggressive? Definitely. But they never figured it out. Wasteful? Not really. They were all cheap-ass hippies who kept the thermostat on 60 all winter (I guess technically I was too, being mildly complicit). Being upstairs in a poorly insulated house with no upstairs thermostat, my temperature would have been in the upper forties if it weren't for the steady hum of my computer and the five dollar toaster oven. Once winter passed, I finally broke down and ran CAT5 down the stairs, but I was happy killing two birds with one stone while it lasted.
You don't happen to both run your routers on timer switches? Solar cells?
Power company doing rolling blackouts? - nevermind, just checking.
Check out Ubiquiti's AirView product. $39 for a 2.4Ghz analyzer. No, really. I have a couple of these and they work. Granted, it's not a $24K Anritsu, but it will get you started. You may just need to switch channels, and this guy will show you if there's noise that it can hear.
where can you see lions?
only in Kenya
come to Kenya we've got lions
where can you see tigers?
only in Kenya
got lions and tigers only in Kenya
forget Norway
Kenyaaaaa
oh Kenyaaaa
where the giraffes are
and the zebra
Kenya Kenya Kenya Kenyaaaaa
Kenya we're going to Kenya
believe it
Try Innsider if Netstumbler fails. It is free and friendlier with WIFI cards. At least you can see if it is a WIFI signal. If it is interference and not a clear WIFI signal, then invest in a cheap spectrum analyzer like WI-Spy. Anyone have an ultrasonic alarm system around? http://www.metageek.net/docs/inssider-user-guide
move to an island a hundred miles away from any transmitting source, mix aluminum flakes in your paint paint the entire house, change the window screens to brass mesh, ground every electrical / electronic device with as short a grounding wire as possible. Or just take a second shift job where you will be working during the effected time.
What about zombie babies?
Official Observers, experienced equipment-heavy hams with experience in signal tracing. The FCC relies on them to _gently_ monitor the airwaves in these days of modern times, when you can't tell the ACs from the DCs...
http://en.wikipedia.org/wiki/Amateur_Auxiliary
http://www.rac.ca/en/rac/public-service/official-observers/
There is nothing wrong with yr Internet. Do not attempt to adjust the picture. We are controlling the transmission - NSA
... but I don't have a WiFi problem. You've got the house wired for Cat5 too. My house is wired for Cat5, and has been for about a decade now.
Here is how I avoid having WiFi problems : I don't use WiFi. I don't need it. so all the problems of remotely brickable routers, abysmal to pathetic security, and allowing the neighbours to jack off to MY porn collection - all of them just don't happen.
There is an old, old joke that a medic student friend once told me :
PATIENT : Doctor! Doctor! It hurts when I [do X].
DOCTOR : Then don't [do X].
Oh, sorry, that's not the solution you're looking for. Oh well, try the next room along the corridor. Bye.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Other things that can cause nasty interference on the 2.4.
- Xbox wireless controllers
- Wireless Keyboards and Mice
- Someones Ham radio project?