Why does my wireless signal speed vary?

August 13, 2004 9:44 AM

Home wireless setup: why does my signal speed vary? [mi]

On our home wireless network (Verizon DSL, Actiontec gateway, Netgear MR814v2 router, Win XP all around), we had two laptops working fine. Signal strength varies, but signal speed is always 11 mpbs.

Now with my new desktop and its Linksys USB54G adapter, not only does my signal strength vary like crazy, but the signal speed goes from 2 to 5 to 11 mbps, sometimes within seconds, with no apparent pattern. As I type it's 2 mpbs, strength low, but two minutes later it'll be 11 mpbs, strength high.

I can't seem to get a straight answer on why. Dell says it's "normal" for a desktop setup to do this. Linksys says no, but since all the firmware and drivers are updated, it's gotta be a problem with the adapter. Netgear can't help either. Verizon and I are not on speaking terms.

Any advice? Could it be an IP address thing? Some sort of interference? All the computers are within 25' of the router, and we live in an old adobe with thick walls, if that makes any difference.

posted by gottabefunky to computers & internet (9 comments total)

It's normal, particularly for 11g, to flop all around in response to signal conditions. Is it actually affecting throughput, or are you just worried because of the numbers you see while you're watching the signal meter?
posted by majick at 9:56 AM on August 13, 2004

It's not an IP address thing as IP and wireelss are totally different beasts. If you're having problems with your wireless connection then it's something with your wireless setup.

things to check:
- most manufacturers offer a "turbo mode" that gives higher speed if you use their products for both the adapter and the router. Unfortunately, this causes problems when using multiple brands. i'd check to see if any of these are enabled.
- it looks like you have an 802.11b router. when connecting to an 802.11b router from an 802.11g adapter, sometimes you need to adjust some settings. "RTS threshold" comes to mind as one of the settings you would want to change.
- Do you have WEP enabled on your router? (Encryption). WEP adds a certain amount of overhead and can cause the symptoms you describe. Try disabling WEP and see if that has any results.
- Does the new adapter work if you're right next to the router? (to eliminate the distance issue)
- Are there any major appliances between your new wireless adapter and the router? like your kitchen for example? many of those appliances cause wireless interference. Fans do too, so watch out for those.

That should keep you busy for a while =)
posted by escher at 10:14 AM on August 13, 2004

a few other suggestions...

Check to see if the card on the laptops will let you change the premable from long to short. That really helped my wife's laptop.

Check the settings on the router. Check to see if it's set for both a and b, if so, then change it to b only.

Get an external antenna. We got one at compusa for like $29 (i think it was) that helped immensly.

Hope something works! Good luck, I know we couldn't live w/o it!
posted by damnitkage at 10:21 AM on August 13, 2004

pn review, i'm a dumbass. Relplce "laptop" w/desktop.
posted by damnitkage at 10:25 AM on August 13, 2004

Wow, thanks for all the suggestions.

- it looks like you have an 802.11b router. when connecting to an 802.11b router from an 802.11g adapter, sometimes you need to adjust some settings. "RTS threshold" comes to mind as one of the settings you would want to change.
On the router or adapter? The adapter is compatible with b and g.

- Do you have WEP enabled on your router?
Nope.

- Does the new adapter work if you're right next to the router?
Can't tell with the desktop, but the same speed thing happens when I use the Linksys adapter with one of the laptops.

- Are there any major appliances between your new wireless adapter and the router? like your kitchen for example? many of those appliances cause wireless interference. Fans do too, so watch out for those.
No kitchens, but there is a cheap floor fan near the router...

Check to see if the card on the [desktop] will let you change the premable from long to short.
Will do.

Check the settings on the router. Check to see if it's set for both a and b, if so, then change it to b only.
Couldn't fine this in the router manager screen...

Get an external antenna. We got one at compusa for like $29 (i think it was) that helped immensly.
To attach to the router I assume?
posted by gottabefunky at 10:34 AM on August 13, 2004

My experience is that, for whatever reason, desktops don't like wireless much (perhaps because they are too electrically noisy themselves?). With this D-Link PCI card, I was having symptoms very similar to those you describe (actually, even worse, since I was getting 1-2 Mbps on a pure .11g network, even if I moved the router to within a couple feet of the computer). I replaced it with a card that came with a decent external antenna, and now get a pretty consistent 48-54 Mbps.

Therefore:
1) Antenna position can be important. Try moving your current USB adapter around. In particular, you probably don't want it too near your actual computer, or with the computer blocking the line of site between the router and the adapter.
2) If neither that, nor the other suggestions in this thread help, consider getting an adapter that supports external antennas. Here's the cheap solution I used; or, if you're not comfortable opening up your computer (or don't have available slots), here's a more expensive USB combination.

On preview: damnitkage beat me to the external antenna suggestion.
posted by kickingtheground at 10:53 AM on August 13, 2004

hey funky, as regards the external antenna, yeah, you'll just unscrew one of the stock antenna's (antenni?) and screw the new one in place. very simple very easy. i see you!
posted by damnitkage at 12:50 PM on August 13, 2004

you'll just unscrew one of the stock antenna's (antenni?) and screw the new one in place

Be careful, each vendor uses a different and very strange connector. Make sure the antenna is actually compatible.

Until recently, it was illegal to plug in an external intenna. Access Point manufactureres were required to use obscure connectors to prevent end users from building their own antennas. The FCC has since relaxed their position on external antennas, so newer equipment may be *more* standardized, but I'm not aware of any standard antenna connector.
posted by Kwantsar at 5:23 PM on August 13, 2004

The wireless Linksys router that I have currently has normal coax connections for the antenna. Prior to this router, I've had a dlink, a belkin and a netgear. All three had the coax connectors. YRMV, but I think that they are making the wireless routers with the normal coax connectors.
posted by damnitkage at 3:31 AM on August 14, 2004