Oscillating signal on SMC card

[nuqlar]

I have recently set up a home wireless network with a Linksys 4 port wireless router/switch on a cable modem. I have one laptop with a Linksys wireless PC card. These items work fine, no problems. I added a SMC wireless card to a newer desktop (<1 yr old Dell) running Win XP. The card sees the network and I can access the internet, but the monitoring program for the card reports a rapidly changing signal strength and link quality. Every 3 to 5 seconds it will go from 100% to 0% and then back. Each time it hits 0% signal strenghth, WinXP generates a small message box at the lower right of the screen saying &quot;wireless network unavailable&quot;. This apparently doesn't interfere with anything long enough to actually disconnect from the network, but it is bothering me.

I would have expected a signal problem to be a constant issue, not highly variable. The straight line distance from the SMC card to the access point is not more than 15 feet, athough it does penetrate two walls and a floor in the process. This doesn't appear to be an interference problem with other appliances (microwave, cordless phone, etc.) because it never changes its oscillation and never stops.

Things to try...
Move the desktop unit to the other side of the desk.
Re-seat the wireless network card.
Change channels from 6 to 11.

I have alread de-activated authentication, but no luck.

Could the card be picking up stray EM from within the Dell machine itself?

Any other suggestions/thoughts?

Thanks,

nuQlar

 

[nuqlar]

Update:

I have tried to relocate the tower from one side of the desk to the other. No change. I have also tried changing channels from 6 to 11. Still no change. I have also brought my laptop into the same room and set it on top of the tower, but the laptop reports a strong unchanging signal from the access point.

I am beginning to think I have a bad card and it is time to call SMC.

 

[bcastner]

Try in the XP Wireless Network, Authentication Tab, disabling 802.1x authentication.

Best.

 

[nuqlar]

I have already tried disabling 802.1x authentication. Thanks.

 

[bcastner]

You are not supposed to use the monitoring program and XPs native Zero Wireless Configuration at the same time.

One or the other, not both.

If you elect to use the Monitoring program than disable Wireless Zero Configuration service under XP. You can Start, Run, MSCONFIG, Services to do this.

 

[nuqlar]

I have disabled the Wireless Zero Configuration service and still no change. I have opened the case and re-installed the card and the drivers. I have downloaded the most recent drivers from SMC's website. I have searched the web for similar problems and I haven't seen this described anywhere else. Other folks who have problems with wireless adapters lose connections after one minute or some longer time period. This signal oscillates every 3 to 5 seconds. Although it reports no signal, it never drops the network connection and I can still access the Internet.

This is driving me nuts.

 

[bcastner]

I am curious if your Task Manager shows some cyclic resource use. If you watch task manager's display of processor usage by task, do you see any co-incidence of resource use by the monitor program?

 

[nuqlar]

bcastner, I will take a look at the task manager and let you know.

I contacted tech support at SMC and their only suggestion was to disable Wireless Zero Configuration. They were even kind enough to give me a batch file that would turn it on and off without having to go through all the various menus. After I explained that I had already disabled WZC and my problem was every 3 to 5 seconds, not every minute, they gave up and blamed Windows XP. I have been researching this issue heavily since it cropped up and haven't seen anybody else describe my symptoms on any other kind of wireless card on any kind of OS. I will try to install the card in another machine running WinME to see if it is the OS.

 

[bcastner]

See if you can get netstumbler to work with the card. I believe it will. See what readings it gives over time.

http://www.netstumbler.com

 

[nuqlar]

bcastner, thanks for your help.

I looked at task manager and couldn't identify any process that appeared to be interfering with the SMC card. There were some small changes in CPU usage as the signal strength fluctuated, but these changes were in the process for Explorer and I think this was a response to the signal change, not a cause of the signal change.

Also, I installed Net Stumbler and found it reported losing and regaining the access point more rapidly than the signal strength was fluctuating on the card monitoring program. Net Stumbler would often report the loss and gain of the AP signal several times each second.

I am becoming more and more convinced it is a bad card. I'll know for sure when I install it in the WinME machine.

 

[inmuck]

Finally I got this working with a Tek-Tip, posted here, here is the details.. (unfortunately I forgot the exact link)

The fix I found did indeed relieve me of the every 60 second disconnect then reconnect. here is the fix; Which I do not take credit for but will post the link below the fix.
Cheers

The windows xp WZC service rescans the network in a span or around 60 seconds to find a better AP - signal. During the time of rescan the current connection can go off or hang-up, based on the distance between the AP and the wireless client. If the WZC did not find a better signal it reassociates itself to the existing signal meanwhile causing drop in the connection.

Disabling the WZC is not advisable because if the WZC is disabled the wireless card won't connect even once. Changing the type of service from automatic and manual is also painful because it has to be done each and every time.

What can be done in this case is to create a script which will stop the WZC service after it connects.

Open a notepad application and type,

@echo off
net stop WZCSVC
@echo on

Save it in your desktop as fix.bat.

Double click on this file which will execute this script stopping the WZC service.

This setup will work fine if you have only one AP, but if you have multiple AP's , executing this script will stop the client from associating to other Access points as it needs the service to be started again. If you prefer to go along with the script execution then you can use this script to rescan the network again...

Open a notepad application and type,

@echo off
net start WZCSVC
@echo on

Save it in your desktop as rescan.bat.

so whenever you move to the range of a new AP you can rescan the network and after it gets connected you can run the fix.bat and fix the disconnection problem

 

[bcastner]

I do not understand how disabling WZC, as you already had it disabled, could possibly help.