Quoted: So is that saying typically I could expect to get 18 Mbps with this card 75 meters away from the airport basestation (or other wireless G router)?
Theoretically yes. Only this has been measured without any wall's or anything like that, just in open space. Also the wireless accespoint has to be able to send this distance.
The USB stick i mentioned above does perform here better than the original Airport Card in my iBook. But ik don't know if it will perform better than the Sonnet PCI card. Because the Sonnet card has a much bigger antenna, so it seems logic to me it has a stronger signal.
The speed should be exact the same. Both adaptor's are 54 Mbps, so should also be able to run at 54 Mbps. Ofcours you should not be to far away from the accespoint.
Here i have a Linksys WAP54G accespoint and my iBook with the Asus adaptor. At this moment i have a 54 Mbps connecton. There is about 15 meter between the accespoint and the iBook and two brick wall's.
Hopefully this is helpfull or solved your problem.
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