Upgrading & Fixing Laptops DUMmIES

If you attach a WiFi card to the PC Card socket of your laptop or to a special-

purpose compartment in the case, you have no choice about the power source

or the power drain on your ability to use other external devices — except by

turning off the switch for the WiFi transceiver or physically removing it from

its PC Card socket. (Be sure to use the Windows facilities to “stop” a device

attached to the PC Card port before removing it from a machine that is up and

running. Windows displays a utility to permit safe removal of a USB or PC Card

in the notification area, usually located at the lower-right corner of the screen.

Click the utility to open it and then choose the device you want to stop.)

If you are using an external WiFi transceiver that is attached to a USB port,

you may improve its, the laptop’s, or another device’s performance by using

a poweredUSB hub, which plugs in to an electrical outlet to assure sufficient

voltage for all attached devices. Of course, if you’re going to plug a powered

USB port into a wall socket, you might as well do the same for the laptop

itself. This sort of solution works well while moving from office to office; it is

less worthy if your machine is meant to be used entirely on battery power.

Fighting frequency..............................................................................

Be aware of possible sources of radio frequency (RF)interference or objects

that shield radio signal transmission:

Wireless telephones, especially those that use the 2.4 GHz frequency

Certain household appliances, including microwave ovens, television

sets, baby monitors, and even improperly shielded PCs

Radio frequency remote controls for garage doors and other electrical

equipment (Note that most modern remotes for televisions, VCRs, and

many other high-tech devices use pulses of infrared light; infrared con-

trols may occasionally interfere with each other but don’t effect RF

devices.)

Another office’s or neighbor’s WiFi system

A high-powered transmitter, especially the sort used by radio or televi-

sion stations or by police or military authorities

Signal blockage comes in many forms, too:

Large metal objects like filing cabinets or refrigerators

Metal netting in plaster walls

Decorative metal ceilings

Certain types of wall coverings or flooring that has metal or other dense

substances

210 Part IV: Failing to Communicate