Why does my wireless speed vary so much, and why doesn't this variation seem to affect Internet performance?

--Fritz Clayton, Las Vegas

If you've ever tried listening to the radio while your car was going through a long tunnel, you know that environmental variables affect wireless signal transmission. A family member turning on the microwave oven or a neighbor booting a Wi-Fi-equipped PC next door can degrade the Wi-Fi signal in your home.

And that interference--if it doesn't kill the signal outright--results in a slower connection. So it's not surprising that your Wi-Fi signal may be slower one day than another.

Why doesn't this reduction in data transfer speed appear to slow your Internet connection? The 802.11g Wi-Fi standard tops out at a transfer rate of 54 mbps. Even if interference cut the actual rate to a fifth of that speed, it would still be faster than almost all American household broadband connections. If you lived in Japan, where speeds of 60 mbps and higher are common, you probably would notice the difference--and the lower transfer rate will certainly hamper the performance of such non-Internet network chores as transferring files from one PC to another. Hope for a strong Wi-Fi connection on the day when you want to transfer several gigabytes from one PC to another.

Or if hope isn't enough, see "25 Questions, 25 Answers" for tips on how to improve your Wi-Fi signal.

Send your questions to answer@pcworld.com. You'll find more Answer Line columns here . Read Contributing Editor Lincoln Spector's humorous and other writings at www.thelinkinspector.com.