I have an Acer 5920G laptop running Vista Home Premium with an Intel 3945ABG WLAN chipset. I also have a D-Link DSL-2740B router and a D-Link DWA-140 Wireless-N USB adapter.
The above kit is relatively new but my wireless issues pre-date them. I bought the D-Link kit as my once reliable Netgear DG834G wasn't providing a stable wireless signal/connection when I moved house. The new router solved this initially but I suspect new neighbourhood WLANs have caused my recent woes to return after a year of relative tranquility.
This tranquility was no thanks to the 802.11n DWA-140, by the way, which much to my chagrin fared worse than my internal 802.11g cards on my old and new laptops. My wife has 802.11g only so I couldn't go Wireless-N exclusively anyway.
My signal strength fluctuates between Poor and Very Good with Excellent on rare occasions. Whatever the signal strength, the connectivity as reported by Vista's connection icon has lately been limited or none more often than not and is very intermittent. I've tried a few DNS/TCP things to no avail.
I suspect environment/interference. The two nearby networks both use Channel 11 and I use Channel 13. I'd use Channels 1 or 6 if I could (the router chooses Channel 6 if Autoscan is on) but once I do this my laptop sees nothing or a very poor signal - and, yes, I reset the channel on the adapter to Channel 6 as well. The same goes for Channel 1.
I've updated drivers on all adapters and the router (which is subsequently very stable and suffers no lock-ups).
I'll try Channel 7 next time I get some peace (4 year old, kitten. wife, day job...).
In the meantime, any theories would be much appreciated.
Thanks for your time if you've made it this far...
Just curious to see if you get a better signal!
Photo #2 shows that you can actually Download and Run the Parabola Calculator/
I know they work, just wondering what it does for your situation!
Get back to me when you get a chance!
Pete
Pete,
I was just about to get creative as per your link when I think I accidentally stumbled upon a resolution...
To say I'm baffled is an understatement.
I was trying Channel 7 whilst I had a spare hour. Failed dismally. With head bowed, I reset the router to Channel 13, shut down my laptop and went off to be a good father to my daughter...
She's now asleep (I explained 802.11n to her between bouts of Noddy), so I came back to turn on my laptop and wrestle with my patchy wireless. I was just about to reset my WLAN card to Channel 11 when Avast announced it had updated its database, before I'd even had a chance to pick up my mouse.
I'm no wireless expert, so excuse my ignorance. Why can I only connect with my router on Channel 13 and why am I able to do so with my WLAN card on Channel 7? I'm assuming because I'm no longer on Channel 11 (as used by numerous neighbours of late), I'll be less prone to the interference I was evidentally getting lately.
I'll try various channels on the WLAN card later to see which gives me best performance, leaving the router on Channel 13. I'll also see if it's resurrected any 802.11n capability via my maligned D-Link DWA-140.
Please can someone explain the relationship between the channel on the router and the channel on the WLAN card and how they interact? And if anyone knows why I can only communicate wireless with my DSL-2740B router if its on on Channel 13 I'd be extremely grateful.
I was just about to get creative as per your link when I think I accidentally stumbled upon a resolution...
To say I'm baffled is an understatement.
I was trying Channel 7 whilst I had a spare hour. Failed dismally. With head bowed, I reset the router to Channel 13, shut down my laptop and went off to be a good father to my daughter...
She's now asleep (I explained 802.11n to her between bouts of Noddy), so I came back to turn on my laptop and wrestle with my patchy wireless. I was just about to reset my WLAN card to Channel 11 when Avast announced it had updated its database, before I'd even had a chance to pick up my mouse.
I'm no wireless expert, so excuse my ignorance. Why can I only connect with my router on Channel 13 and why am I able to do so with my WLAN card on Channel 7? I'm assuming because I'm no longer on Channel 11 (as used by numerous neighbours of late), I'll be less prone to the interference I was evidentally getting lately.
I'll try various channels on the WLAN card later to see which gives me best performance, leaving the router on Channel 13. I'll also see if it's resurrected any 802.11n capability via my maligned D-Link DWA-140.
Please can someone explain the relationship between the channel on the router and the channel on the WLAN card and how they interact? And if anyone knows why I can only communicate wireless with my DSL-2740B router if its on on Channel 13 I'd be extremely grateful.
Many thanks,
A happy, yet somewhat confused, Professor Yaffle
OK, that was a fluke - Channel 7 playing up now. so I am lost. My questions in bold quoted above are still valid if anyone can help.
When I get a day off soon, I'm determined to get to the bottom of this - any things worth trying?
At the risk of talking to myself, I thought I'd post an update in case it helps others. My connection has been stable for an hour after I...
1. Changed router security encryption to WPA2-PSK as opposed to WPA-PSK.
2. Changed router channel to "1" and rebooted (autoscan chose "1" but I've turned that off for now whilst I test things out)
3. REMOVED Vista network connections and set up from scratch
4. Changed default ad-hoc channel to "1" on WLAN devices
It appears that if the channel on the router changes, most if not all WLAN clients will scan all channels irrespective of default channel on client, hence why I connected previously with seemingly non-overlapping channels (router=13, WLAN=7). So that solves that puzzle.
WPA2 offers better Wi-Fi performance and better security than WPA if your router and clients support it.
If you do not remove wireless networks in Windows and re-configure the security on the router, you may end up with the message that insists the settings on the PC do not match those of the network. even if you re-align them via the connection's Properties. Removing and adding the network from scratch solves this.
I'll retry Channel 6 or 7 next, as 802.11n requires a mid-range channel to fully utilise neighbouring channels to boost range and speed - so a mid-range channel offers more non-overlapping channels (above and below) whereas 1 and 13 are at the beginning/end of frequency so can only offer half as many, therefore half the performance. Or something like that!
Also, there's a Beta of the DSL-2740B firmware (2.73) that improves 802.11n performance (2.0 standard?), so I'll give that a shot too - updating has proved painless thus far so I'm hopeful I don't brick the thing!
After days of flawless wireless I went into the router to try Channel 6 (to get the best from 802.11n, which is no better than 802.11g at present - or certainly it wasn't when it worked - read on...). I then noticed that I had inadvertantly chneged the router to broadcast 802.11b and 802.11g ONLY hence why the chnanel change (from 13 to 1) finally worked last time round.
As soon as I enable 802.11n, the router seems to be OK with all LEDs correct but nothing can talk to it, not even the 802.11n dongle. There is a weak signal sometimes when I scan for networks but any attempt to connect is met with no response received from the router. Connecting via Ethernet and all is fine, so it's a wireless issue.
Back in 802.11b/g only mode, all is well again and the network is very stable indeed.
It's annoying me that I've got 802.11n kit but can only use it in 802.11g mode!
I've finally revisited this issue in an attempt to get 802.11n working as expected now that I do more streaming.
The router's in Mixed 802.11b/g/n mode and 802.11g performance is good and the router is very stable (firmware v2.73).
What I can't fathom is why signal strength and throughput is so poor via the 802.11n D-Link DWA-140 USB dongle I also have. If anyone has a good signal/data rate with 802.11n in a mixed 802.11g/802.11n network, I'd be interested in their wireless settings on the router. I suspect part of the issue may be that Channel 1 is used (it's the most stable) but from memory Channel 6 was no different.
I have also forgotten the cunning URL that allowed me to connect to the router via my mobile phone's browser. I'm sure it did not involve an IP address: it was some other form of unque ID. This was very handy when testing as it meant I could reboot the router without connecting to it via Ethernet when the wireless settings I was testing made the router inaccessible wirelessly. Can anyone point me in the right direction?
Please pick the bones out of my Wi-Fi Woes! 
Linear Mode
