WiFi Connection Quality

Easy. Let's do the math. Without doing anything unusual, the typical range between a commodity router and a generic laptop follows this table: I got the numbers from Intel. I later realized they were a bit optimistic, but didn't bother changing them because I figured that improvements in semiconductors and antenna designs would make them more realistic. It did.

For every 6dB increase in antenna gain at one end of a path, the range doubles. A top of the line antenna would be a barbeque grill style dish, such as one of these:

24dBi is 4 times 6db gain, so the range would double 4 times, or 2^4 times = 16 times. So, if you attach a 24dBi dish to your router, you should get 16 times the range.

So, if a laptop to router connection, with the stock antenna runs at

24Mbits/sec, you should get 140ft range. Add a 24dBi antenna, and the range will be: 16 * 140ft = 2,240 ft = 0.424 miles

Of course, there are a few limitations. If you put the dish on your roof, and the router lives inside the house, you'll have some coaxial cable losses that will reduce the range. I'm also assuming that whatever connection speed your running is the same with and without the dish.

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When you tear it apart, the WRT54GL will look like the board on the left: The WRT54GL is identical to the WRT54G v4.

Now that you mention it, I have had quite a few failures of Linksys (and Netgear) switching power supplies on their routers. It's worth checking or just substituting a different power supply. I don't have any Linksys PS photos, but here's the equivalent Netgear: I don't recall replacing any electrolytics inside a WRT54G/GL but having those fail after so many years is certainly a possibility.

My pile of dead electrolytics: Most came from PC motherboards and power supplies. The pile is about twice as big today.

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Jeff Liebermann

iFi_Router

I haven no idea what that does. My connection is through a Ubiquity receiv er which is terminated with an Ethernet connection just like a port on the router. Nothing to log into, so not useful to me.

So I've lost track. Is there a unit under $50 you recommend rather than ju st agreeing that it might not be the worst unit?

I don't agree with your assessment. I am buying a replacement assuming the WRT is defective. The reason for going with a router with some features i s so I won't need to buy a new unit next year. Otherwise I would buy one o f the cheapest units (~$10) to just show the WRT is/is not defective. Not much point in that really if I then need to buy a new router.

I'm getting some criticism for not following all the advice I've been given . That is because those who keep giving that advice are ignoring the info I am providing. Actually I'm not ignoring the advice. I'm getting a new u nit that will let me distinguish the two possibilities (defective router vs . interference from my refrigerator or car radio even while not running).

Rick C.

Reply to
gnuarm.deletethisbit

I can't argue with the math, but does it really apply here?

If the objective were to get better signal on the wisp link between two FIXED antennas, sure...but...

The circumstances here are not the least bit demanding. I don't recall whether the OP tried placing the laptop close to the router. I'm assuming he did and that didn't help.

The objective is not to get more gain in one direction. Typically, you'd want coverage in all directions for a home WiFi situation. About the best you can do is a vertical collinear antenna that compresses the vertical direction and puts the power in more of a doughnut than a sphere. That probably won't help an interference problem.

I just had my FIOS ONT replaced. The symptom was that about 9PM every day, the internet disappeared for an hour or two. Worked fine other times. Classic interference problem. Well, after a week of experimentation, I finally convinced Frontier to come out and fix it. Replaced ONT. Problem solved. The problem ain't always the most likely.

Reply to
mike

The Asus RT-AC1200G or RT-AC1200GP is acceptable. The Asus RT-AC1200 (no G) is not acceptable. The Tenda AC9 AC1200 is probably ok. Remind me not to bury you in details.

I don't think you're going to find a dual band wireless router for $10.

Ok, I yield. Your approach of buying something that will last is as good as any. Personally, I like to know what is causing the problem before I throw money at it, but under the circumstances that you describe, your approach is good enough. By replacing the router, we'll at least have a clue if the problem is interference.

I'm one of those ignoring your information. Nothing personal, but I have to deal with customers on a daily basis that tend to bury me in trivia while leaving out important details. I really only care about what problem you're trying to solve, what you have to work with, what you've already done to solve the problem, and what happened. Everything else goes into my /dev/null. I do this in self defense because if I considered every trivial detail, I would never get a decent picture of the situation. It's difficult to fix such flaky connection problems, especially from 3000 miles away.

My posting listing possible non-802.11 and non-Wi-Fi sources of interference was at the request of someone else asking for such a list. Even so, it wasn't necessary for you to comment on each item as if you were cross examining my advice. When I was answering such questions in alt.internet.wireless, I posted such a list to someone that was having problems, who rejected everything on the list. A week later, I get an email indicating that he had found the problem. There was a new rather strong 5GHz wireless link going directly over his house that he hadn't noticed. So, don't just reject everything on my list out of hand. Look around, and maybe you'll see a dish pointing at you in the distance. Maybe your neighbor installed some kind motorized spark gap transmitter. Maybe your forest isn't as much an RF brick wall as you think. Just think about it using the list for hints.

I wouldn't write this much if I didn't think you were listening.

Got it.

Incidentally, you asked about interference from LED light bulbs. It's rather strange. I bought about 6 of them at the same time, all the same. Two produced so much EMI/RFI that I couldn't use some of my ham radio equipment when they were lit. The other 4 were dead quiet. I haven't bothered to tear them apart and see what's different (or blown) but I suspect some sort of manufacturing defect in the one's making the noise.

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No, it doesn't apply. The connection between the house and the WISP is via 900MHz and is probably located on the roof. The Wi-Fi connection to the Dell Precision M6800 laptop is indoors and currently on 2.4GHz. Add a 3ft diameter indoor 24dBi dish is probably not going to do much to improve the 2.4GHz link reliability, especially over a very indoor short range. If anything, it will probably make it worse because Wi-Fi equipment has a lousy receive dynamic range and will probably be overloaded by the strong signal from the dish antenna.

The house to WISP link is a done deal. As was previously mentioned, the WISP already did an upgrade to that link, which improved that connection.

That would be an obvious test and I suspect he also did that.

I like to diagnose things by substitution. He's about to substitute a new wireless router, but what if that doesn't fix the problem? The next step is to substitute a different laptop and see if that helps. Not much else that can be replaced. Maybe wrap the house in aluminum foil?

Agreed, although I've had very good luck with indoor coverage problems using lower gain (8dBi) patch antennas. They work best when the wireless router is at one end of a long narrow house. If the router were in the center of the house, I would probably use an omnidirectional antenna. The danger with these is getting one with too much gain. Above about 12dBi, the vertical beamwidth becomes very narrow and usually has some uptilt. Not a major problem with a perfectly flat house, but if the house has multiple levels (like mine), it won't work.

Incidentally, favorite Wi-Fi antenna is an AMOS or Franklin antanna: Lots of gain (about 14dBi), 120-150 degree horizontal beamwidth, 8 degree vertical beamwidth, easy to build, and easy to hide (even indoors).

I also would have guessed interference. I see similar issues with Comcast wireless "gateways". The cable modem and router work just fine, but the Wi-Fi in some of these is horrible. It usually goes away after about gateway is replaced.

RF is magic. Wi-Fi is close to magic.

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snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:

I told you... The OS replacement ALSO allows you to max the power of the unit, which is NOT the current circumstance. It also has other pro router settings that the base OS handcuffed you on.

And YES, a good 9dBi antenna would improve rx and tx.

Reply to
DecadentLinuxUserNumeroUno

Jeff Liebermann wrote in news: snipped-for-privacy@4ax.com:

Cisco bought linksys first.

Do you dislike Asus or think the quality will suffer?

Asus had one of the first and fastest USB a/n/ac wifi interface sticks.

They have a line of routers before this acquisition as well.

Reply to
DecadentLinuxUserNumeroUno

could well be, I had the linksys power brick go bad on one. I replaced it with a generic wall wart and reliabiity improved.

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Reply to
Jasen Betts

t_WiFi_Router

eiver which is terminated with an Ethernet connection just like a port on t he router. Nothing to log into, so not useful to me.

I can read two messages back. I'm talking about one you would buy yourself . You said you wouldn't buy any of these because they aren't "supported by AsusWRT Merlin firmware". So are there any that meet this requirement tha t are still close in price to the $44 unit?

I'm not poor, I just don't like investing money in things that don't provid e a potential benefit. If the "Merlin" support is something that is worth $5 or $10 extra I'd rather get that than risk wanting it down the road and having to spend another $50 to get it.

To figure out if the WRT is wonky won't require a dual band router. The du al band and 1000 Mbps Ethernet are in the list because I want to *not* just debug the problem at hand, but fix all of today's problems and potentially fill all needs I'll have for the next 5 years. I used a direct cable conn ection a few months ago to copy files when setting up up and/or returning P Cs. It would have been more convenient to use the router for that even if with cables.

Time is money, no? I am going to mail order this most likely. I'm not ver y near any computer stores. So I'd just as soon get it fixed as well as di agnosed. $50 is actually pretty chump change since it should fix the probl em no matter what the cause.

I knew that. But there really is virtually no chance there is anything her e other than signals from one neighbor who isn't home and my house which ha s literally *nothing* high tech in it that is currently running.

It's not actually "flaky". The level of dropped packets is relatively cons tant regardless of whether the PC and router are 1 foot apart or 30 feet ap art. That alone says to me the issue is not interference.

Of course, I was just trying to show how this location really is like Ted K azinski's cabin.

What does that mean? What is at 5 GHz that could pass over a home in rural setting? I suspect your friend was in a much more urban environment.

I can only see a small number of neighbors. A dish pointing at me would ha ve to be either malicious or have fallen off the house.

Ham radio is at a range of frequencies. Do any of the LEDs interfere at 2.

4 GHz? That would be quite the range of noise.

Rick C.

Reply to
gnuarm.deletethisbit

Not on the roof. The WISP provider told my neighbor they put them low (like below the second story deck) to shoot "under the trees" in the yard.

The WISP link is not at issue because a direct cable from PC to either the WISP modem or the router both work fine.

1 to 30 feet do not show a difference.

How about replacing everything else other than the PC? That works well. (Panera, another home, etc)

Good thing for me the nearest Comcast unit is some 15 miles away.

Rick C.

Reply to
gnuarm.deletethisbit

Sorry, I screwed up. I originally thought that the AsusWRT Merlin firmware would work with the RT-AC1200G and GP. Later, I discovered that it will NOT, but forgot to go back and edit my message. For my purposes, I prefer the Merlin version of the firmware, which I have running on various Asus RT-N66U and RT-AC66U routers in service by my customers and at home. There are some features that I need that you are unlikely to require. You could do as well with the stock Asus firmware. I might be looking for router upgrades since AsusWRT Merlin firmware development has stopped for the these models (but continues with others). As I vaguely recall, I paid about $50-60/ea on Newegg and eBay for refurbished, used, or "needs repair" routers.

I just got off the phone with an elderly customer, who happens to be quite wealthy. He thinks nothing of doubling the size of his solar power system, but just spent 30 mins on the phone with me trying to squeeze a few dollars out of my bid and estimate. He's pathologically cheap, but otherwise a very nice person. Incidentally, he was a residential home contractor in his day, and seems to have built his house from leftovers from his construction projects. Methinks you can image what that looks like.

Anyway, it's not worth anything extra to be able to run the AsusWRT Merlin firmware.

I'm thinking back where we were in wireless routers 5 years ago. You would have been able to buy the very earliest 802.11AC routers, and some rather marginal 802.11N routers. They probably would have lasted

5 years of service if you bought them from a manufacturer that actually believes in keeping their firmware up to date. That's also important for keeping up to date on the latest exploits. A quick check is the date on the routers last firmware update. If it's really old, it's unlikely to get any further updates. If it's fairly recent, you have a chance.

Yep. Gigiabit is nice. There are some cheap routers, such as the Asus RT-AC1200 (non-G) which I stupidly purchased, that lacks gigabit ethernet.

Ok. Purchasing something is your biz. I suggest refurbished, which tends to be much cheaper than new.

It's not interference. That leave the router, or the laptop as the possible culprit. Try a different laptop if possible.

My various ladyfriends first reactions to seeing the inside of my house is "You live like that"? It's usually downhill from there.

This was in an isolated residential community surrounded by forest for at least 1 mile. It has the density of a suburban development, but the location is rural.

The spectrum analyzer plugin that I was using quits at 1200MHz, so I don't know for sure. My router is located about 3ft from the LED lamps that were giving me problems. I suspected that there was some kind of imparement, but never bothered to look for any. An easy test is to run iPerf3 and see if the LED light makes any difference. I'll do that tonite.

There are a few videos on YouTube showing LED lighting interference to TV reception. This page quits at 300MHz, but shows the extent of the problem: I'll see if I can find something better later.

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The N in RT-N66U means the fastest air protocol supported is 802.11n while the AC in RT-AC66U means it supports 802.11ac. I haven't figured out what the U means. I see RT-AC66R units which seem to include 802.11d and 802.3 (both units support 802.3u).

I've placed a bid on a RT-AC66U on eBay. Lots of units there, many without power supply or antenna... odd.

I'll likely get this unit for less than I would have paid for another, so no problem.

As I've indicated I have used the laptop elsewhere where it works fine.

I only meant in regards to the RF environment. But I'll refrain from passing any judgement as I do live in a glass house in that regard.

What is the nature of this 5 GHz signal?

I remember when CFLs were new a friend used one in the living room and the TV remote would not work when it was on. Not RF exactly, but the light must have been pulsing enough to interfere with the IR remote.

Rick C.

Reply to
gnuarm.deletethisbit

That actually works fairly well if the trees are well spaced. However, if the path is fairly long, the Fresnel Zone hits the ground and the trees, potentially causing problems. Also, if someone parks a big truck under the trees, it blocks the RF path. A friend setup a link like that which crossed a small parking lot. Every day, the link goes down when the UPS, Fedex, USPS, etc trucks arrive.

Too much paperwork. Just buy some fiber optic cable, protected it with plastic sprinkler pipe, and run it between your house and the ISP. After that, all you need is to get a better wireless router.

I've installed wireless "extensions" between where the Comcast cable ends, and nearby communities without any service from either the Comcast or AT&T monopolies.

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Jeff Liebermann

Yep. Cisco paid $500 million in 2003, and sold it in 2013 to Belkin for an unspecified amount (possibly at a loss). Foxconn then paid $866 million to acquire Belkin.

Are those my only choices? I don't like any of the consumer grade wireless router manufacturers. All of them have their problems. However, occasionally, usually by accident, one of them produces some decent products. I think the Asus RT-N66U and RT-N1200U are among the better products. I'm not so sure of their more elaborate and expensive routers because I haven't tested or used them.

"Sticks"??? Oh, USB. Most of those are bad compromises between size and performance because of the undersized antennas. With an RP-SMA connector and external antenna, they're probably ok, but with the internal serpentine, PIFA or chip antenna, nope.

They? Asus? They were's acquired by anyone.

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Jeff Liebermann

In my case it would have to be a big boat... a *very* big boat since the ho use is some 20 feet or more above the water line and the line of sight for the antenna is closer to 30.

I meant for testing... or are you making a joke? A smiley would help... :)

How do you get the approval from Comcast to do that? For all practical pur poses that is what my WISP is doing. His provider is Comcast in Richmond ( which can show as my location sometimes). Obviously he has a contract with them. If you were to wire a neighborhood for Internet access like my prov ider does, how do you set up the arrangement with Comcast?

Of course there are other issues like approvals for a tower and such from t he local government. My WISP has had problems with the tower thing before. The county was at one time thinking of bringing Internet to the whole cou nty via WISP, but balked at a small tower my WISP wanted to add to a small community because there was a cell phone tower they wanted him to use about a mile away. In the end it went up, but some months later than he wanted to do it.

Rick C.

Reply to
gnuarm.deletethisbit

Well, lets see where the Fresnel Zone hits the trees or ground. I'm going to guess that the tree trunks have about 10 ft of vertical clearance before one gets into branches and leaves. That puts the LoS (line-o-sight) at half of this, or 5ft off the ground. At 918MHz, the maximum path length that will NOT hit the branches or ground is:

0.02 miles = 106 ft. Presumably, your path length is longer than 106ft and does work. Stay tuned to the next exciting adventure in the weird world of RF for why it works.

I don't do smileys. Let's just say it's both a joke and a suggestion. I've done the fiber in plastic pipe trick several times. There are several such runs crossing the paved dirt road in front of my house. At one time, I had the neighborhood wired for shared satellite TV and later shared internet using a mix of coax, fiber, wireless, and twisted pair. I've also done absurdly long runs of CAT5 and fiber in order to distribute internet access. Some were across open country, under a railroad track, through the forest, and across a river. Wireless is the easiest, but also the least reliable. The alternatives also have their own collection of disadvantages, but may still be usable. Think about it.

I didn't get approval. The reselling of bandwidth is specifically proscribed by the Comcast Terms of Service. There are several stories, some of which are long and complexicated. Near the end of one, the County of Santa Cruz asked a good question of Comcast. "Why was Comcast *NOT* providing service to these communities"? After some effort, some of the communities were able to obtain service because the county wrote them into the contract. See line extension fund on Page 5 of the settlement agreement: Other communities received service because an overbuilder threatened to do it first. Rather than loose potential customers, Comcast caved in and decided to provide service.

I have no idea. When I was marginally involved in the negotiations, Comcast kept repeating that they do NOT offer service to anyone reselling the bandwidth. They will provide service to a business, but only if the service does NOT cross property lines. It's in the ToS somewhere, but I'm too lazy to look it up right now.

We have a local ISP that provides licensed wireless service. At this time 100Mbit/sec symmetrical for $100/month. As a CLEC, they also can provide telephony: and fiber: or both: Towers can be an issue, but since the county government is one of the biggest customers of the service, things tend to go fairly smoothly, unless someone goes over the top: (It's in Spain). We've had a functional tower ordinance in place since about 2002 (I was on the committee). See 13.10.659 thru 13.10.668 at: Nobody really likes the ordinance, but it mostly works.

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You make so many assumptions. The path is largely over water, ~ 1 mi. The last 800 feet have a land prominence about 400 feet wide with trees and no visible air gap below the branches since they are up and down the 20 - 30 foot hill. Then 150 feet or so of water with about 150 feet of slope up to the house with the antenna about 10 foot off the ground. Regardless of wh at the WISP operator says, there are no air gaps of tree branches since the trees are at different points on the slope. Not lots of trees though. I think he just doesn't want to climb roofs and likely that wouldn't be high enough to get above the trees anyway. It would get the middle of the Fresn el zone more off the water though which might be the only thing you can act ually accomplish.

Mucking with the Fresnel zone doesn't kill the signal, it just reduces it.

:)

I have no idea where you are going with this now. I don't think anyone wil l let me lay fiber in pipe the mile across the lake.

Not much to think about...

When I looked at the T&C some years ago when I had Comcast it specifically forbid me from even sharing it with another household much less selling it.

I was surprised when I found Comcast provides wired Internet to the nearest town which is very, very small. A friend claimed she was getting some 30 Mbps some years ago before anyone I knew had that sort of rate. But she ha d to move to just outside of town on the other side and had zip there. I'm 10 miles from there, so not much chance of getting Comcast here... except I think they may have bought one of the WISP providers. Their prices are h igh and the contract reads like you were getting a cell phone contract. No guaranty of any given bit rate, but you have to pay for whatever they prov ide.

Yes, that's what I read.

Some of the towers I've seen are bad. Some try to pass as trees, but look worse then the towers.

Rick C.

Reply to
gnuarm.deletethisbit

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