The microwave will kill the signal every time.
Bluetooth, phones and the wireless keyboard/mouse have not interfered with the signal.
As far as dd-wrt and the linksys firmware, I found no difference in signal strength.

What channel are you using? These router usually default to channel 6. Try channel 1 or 11.

Or, if you have an Android smartphone (might also be availabe for iOS, don't know), you can download wifi analyzer to see what channels are most heavily used near you, and choose a channel that has the least utilization. Plenty of ways to do it on your laptop also, just easiest way to me is on Android. We actually use that application at my work.

Since my last post I tried channel 14. The T400 did not like that. I'm now using channel 13. I disabled the cell phones bluetooth links to the home phone. I searched to find what channel the cell phones link to the phone system but found nothing. Only suspects remaining in the house to test for interference are the HTPC wireless peripherals and the microwave oven. I am heating a cup of tea in the microwave as I type and the oven is about 14 feet away. Not really sure, my wireless connection seems snappier on channel 13, but iperf says I'm getting about the same throughput of about 22 Mbps. I'll see how things go the next several days.

No smart phones here, just inexpensive flip phones. To my knowledge there are no other 2.4 GHz wireless devices around here except what is in my house --- I live in the woods. Other than the wildlife, nearest neighbors are measured in terms of "forties" --- forty acres. And all of them are technology luddites --- no computers, cell phones, etc. One doesn't even own a TV.

I'm currently using a D-Link OEM-rebranded ADSL Modem+Router from AT&T with it's own proprietary firmware. Works fairly good though, and can be detected from on the other side of the house.

I was using a Zoom X6 based ADSL+Router prior to this one, but I had problems with it after about 2 years.

Before that I had my WRT54GL 1.1 with a AT&T Speedstream ADSL modem. The Speedstream was replaced by a Zoom ADSL modem. It was after I put on DD-WRT that I noticed that it started to have issues with dropping connections over wireless, refusing authentication, and even locking ports up preventing devices from reconnecting until I rebooted the router.

From my experience, D-Link is my now preferred brand. Check out Belkin also. I've heard good stuff around them. Any other brands.... I'd avoid them. Linksys/CISCO is okay, but you can do better at times for an SoC router. Same goes for Netgear.

Off topic, but I will admit I envy you where you live. I grew up in a region similar (although not THAT sparsely habitated), and I've missed it ever since I made the sacrifice of living in cities in order to have a good income.

And he is probably saner than the rest of us. Hope he has a good library and/or a large wine cellar.

I didn't know channels above 11 were accessible or has something change in the very recent past?

I believe 1-11 is alloted for use in North America and 1-13 in Europe. Or something like that. The wildlife around here can't tell the difference and with me being so far from the road and other people, I figure I'd adopt their way of thinking.

When I'm using wireless, with or without a router, it drops randonly, just like the problem Woodsman is having.

When I do use wireless with a router (I've got two, a linksys and a tplink, both with DD-WRT that I installed), it still does the same thing, and did the same thing *before* I installed DD-WRT on them. It's *NOT* DD-WRT that is the problem.

I also use wireless with an AT&T aircard at the moment and I *still* have the same problem of random disconnections, like what Woodsman brought up in his original post. DD-WRT can't be installed on that little thing, so again, I say it is *not* DD-WRT's fault.

When I use wired on either of the routers, all is well with the world and I'm a happy man. (it's simply faster too and easier!)

Oh! One other thing...when I'm downloading large files (so far anything bigger than 100MB), it's a guarantee I will lose the connection at least once. If all I do is *only* surf the web and keep my 24/7 connection, I don't get disconnected anywhere near as often, but a download of a movie is a real PITA.

Same here, no expensive 'smart phones' with the expensive plans...I've been using a simple flip-up tracfone for the past 6 or 7 years.
Have the same neighbors...not a one of them should own a computer in the first place.
And, I too am way out in the woods (the AT&T aircard I write about above? Even with an external antenna, we still only get three bars. My Tracfone I have to walk around outside to find two bars to be able to use it).
We haven't had a teevee for 4 years now and I couldn't be happier.

Sounds familiar: Tracfones here. Usually I get only one bar from within the house and sometimes that varies which side of the house is the "good side." Outside by the firewood shelter I can get two bars, but even in the house sometimes I get three bars. A mile down the road and the signal stays strong at 3 bars. In town 7 miles away I get five bars.

The best spot in the house seems to be leaving the phones on top the kitchen window sill, which is why I had been using bluetooth to link to my home phone system. I don't use the cell phones much except when I'm away from the house. I thought about a repeater or amplifier but I climbed my TV antenna tower and still had only one bar with the cell phones. So no sense bothering.

The main house phone is VOIP with the local ISP. Works real nice 99% of the time, although an occasional storm will cause dropping/breaking. Still better than the AT&T crap. With VOIP I get unlimited calls, unlimited long distance, caller ID (no solicitation calls anymore!), call forwarding, call waiting, blacklisting, and I pay $7 less per month than AT&T who wanted more money for anything other than the basic connection.

I did some reading about bluetooth. If I understand correctly, bluetooth signals hop and skip all over the 2.4 GHz spectrum and probably is not causing interference. I don't know how the HTPC wireless peripherals use the 2.4 GHz band. There are just too many variables and deciding the cause of the drops likely will take many weeks or months.

What wireless card are you using? If rebooting the laptop means being able to obtain a connection again then perhaps the problem is at the laptop end, possibly the wireless driver.

Try and see whether you can reconnect to the router after using modprobe to unload and reload your wireless driver.

I used to have a lot of problems getting/keeping wireless connections with wicd, but NetworkManager has been OK (touch wood, fingers crossed). I'm using a Linksys WRT54GL, with Tomato (and using my previous router/modem, a Netgear DG834G in modem-only mode).

I've started seeing a similar problem over the last couple months, wifi will drop and get stuck connecting or authenticating and I have to reboot. I don't believe it is the router as multiple other laptops, 4 android devices and a printer all stay connected.

I disabled my bluetooth connections from my cell phones to my home phone system. I have not seen any drops the past few days but at this point I'm considering that only coincidence.

I've had the HTPC on several times (wireless mouse and keyboard) while the laptop was on and no drops.

There is a setting in DD-WRT to "play nice" with bluetooth and I enabled that.

The (rural) ISP uses both 900 MHz and 2.4 GHz. The equipment at my house is 900 MHz. I probably should ask whether any neighbor customers are using 2.4 GHz. The ISP uses 2.4 with customers who have perfect line-of-site connections to the access point towers and 900 with those who don't. As I'm surrounded with trees, I'm guessing any neighbor customers who might have 2.4 equipment likely are not causing interference because the signal likely deteriorates significantly around my house. Plus I believe I'm the last customer in the line of sight with the access point my equipment connects. That is, all other customers would have their equipment pointed away from my house rather than toward. I'm just speculating and the equipment at the access point could be sending 2.4 signals.

The ISP owner has told me a few times the local power company workers use radios that often cause problems with his network. Officially the workers won't admit that because that would be a confession they are operating their radios at unlawful power levels. I don't know what frequency those radios are operating but I presume 900 MHz because I have seen my ISP connection freeze or disappear for minutes at a time.

Much of what I have read on the topic indicates that, overall, wireless technology basically sucks. So I suppose my drop offs are nothing new or unexpected. That said, I am surprised that the software (NetworkManager, drivers, etc.) are not more robust in reconnecting lost signals and that more often than not I have to reboot to reconnect.

There could be more than one cause at play, each masking the other.

This is one of those problems that requires time to debug. Too many variables.

I noticed something peculiar while testing a different problem. Just a few moments ago, after a reboot, the laptop would not connect to the internet.

I could ping my own router, which is configured as the system gateway for all computers in the house. Yet I could not ping the VOIP box to which the router connects. The router is on subnet 192.168.1/24 and the VOIP box is on subnet 192.168.2/24.

Computers -> Router -> VOIP router -> ISP CPE

Curiously, again rebooting the laptop resulted in me being able to ping through the router to the VOIP box.

Before rebooting, I tried several times to restart Network Manager to no avail.

I had not paid attention previously whether this is where I am experiencing the drop. Regardless, I'm confused why rebooting the laptop resolved the problem. Rebooting the laptop does not affect the router->VOIP router connection.

Ideas?

Can you disable ipv6 and see if that helps?

http://www.linuxquestions.org/questi...e-ipv6-937447/