i have had my revo for about 6 months now and its wifi signol is always at low/very low.
this instructable is easy and requires very little skill and no soldering.

Step 1: Things You Need

going clockwise all the tools you need.
wera esd screwdrivers(any old screwdrivers will do)
a drill or brace.
an antenna
the wifi pigtail lead(can buy of ebay for about a pound i got free shipping from china

Step 2: The Start

just a small note:
i am by no means telling you to do this.
this may damage your pc.
invalidate your warranty.
may curs injury to yourself.
wear all protective equipment.
be trained and competent with all tools used.
i am not responsible for any of the above happening to you or anyone else.

start by drilling a hole through the case just big enough for the screw end of the pigtail lead to go into.

Step 3: Connecting It All Together

unplug the main plug on your wifi card and plug the pigtail lead on.

Step 4: And Your Done

fix the back of the revo into place(you may need to cut some of the inside out a little to get the back back on.

tighten the screw end with a pair of pliers.
and your done like it or not.
it did only cost me 1.58p and an old router antenna i had.

please comment this is my first instructable