Based on my experience with my Xoom tablet, with the signal between -90 and -80, it sometimes can't lock on. Sometimes one bar shows, other times, none. If the signal stays about -80, I'll get one bar and the connection is fairly consistent. My router is in one corner of the basement and the Xoom is on the second floor, in the opposite corner of the house. I bought a cheap ($2) booster antenna on Amazon, and if I tilted the angle somewhat, it helped. Then I bought another antenna with a 6' cable and was able to locate the antenna on the first floor above the ductwork. That was just enough to make the signal consistently strong enough to avoid dropouts.