Losing WiFi on my Dell Studio 1458

The F2 button turns off the wifi radio. Unfortunately, I am always mistakenly hitting F2 when I want to rename a file. I have just discovered through trial and error that it is actually double hitting the F2 that turns off the wifi, and another double hitting that turns it back on. However, when turning it back on, it takes a few seconds before it changes to the * and then show multiple bars.