There were many PowerBook G4 models/variants.
The requirements for WPA with AirPort (802.11b) and AirPort Extreme (802.11g) cards were:
- Mac OS X 10.3 or later
- AirPort software version 3.3 or later for the AirPort Card
- AirPort software version 3.2 or later for the AirPort Extreme Card
If you wish to use WPA2, or if there is a problem with WPA or earlier security protocols, with radio modes or speeds, you may want to try a USB wireless (Wi-Fi) adapter instead, as indicated by BDAqua. The problem with USB adapters is that they need special driver software. If Mac OS X 10.5 is not possible, there may be a few USB adapters available with support for Mac OS X 10.3 or 10.4 (often difficult to find, but examples may include versions of ASUS USB-N13). Check specifications and requirements before you buy.
An external wireless Ethernet bridge (connected to the Ethernet port of the computer) could be another alternative, albeit not as small as a USB adapter. There are such devices (also known as gaming or media adapters) from several manufacturers. Netgear WNCE2001 and Linksys WET610N are merely two examples. Normally, a separate power supply is needed as well (although the WNCE2001 could use USB in some cases). Typically, a wireless Ethernet bridge setup can be done via a standard web browser (it does not have to be on the computer where the device is to be used later). Special driver software is mostly not needed, thus allowing the wireless Ethernet bridge to work under almost any operating system (even on some very old Macintosh computers, as long as they are Ethernet-capable). Some of the Wi-Fi range expanders have an Ethernet port, and may be used in a similar way.
