Try this before spending any money. It took me less than 1/2 hour to make a couple of antennae for my WR54GS. Look for the 2.4 Ghz model.
http://www.freeantennas.com/
I have a linksys WRT54G router and would like to increase signal in my new multistory house. Should I get a high gain antenna kit and/or a a range expander? Does the range expander slow down the data transfer process? Thanks!

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