This is an archive of an article that lives ---> http://www.frars.org.uk
An easy to add, external antenna connection for the compaq WL100 prism 2 based PCMCIA wireless lan card.
Once the cover has been removed, examine the PCB and look at the existing antenna configuration. There are basically two 0db gain 1/4 wave antenna's etched onto the PCB. In the centre of the board are gold pads used in the manufacturing process to test the card.
Get the UT141 and terminate one end with the SMA line socket. Then cut the UT141 to about 40mm long. Prepare the end to be soldered, and leave about 3mm of centre exposed. Clean the outter of the UT141 with some scotchbrite or similar to remove any debris.
Looking at the diagram, you will see the location of the hardline with respect to the board. Using a fine knife, cut the pcb track that goes to ANT1, just above the soldered connection to the UT141 centre conductor.
Again examine the picture beforehand to get an idea of what you are doing.
Using this simple technique, good amounts of power can be obtained from the card. The measured output is in the region of 35mW.
Another modification for the more adventureous is to remove the antenna diversity switch and tap the external connection directly to the T/R switch in the card. This requires disassembly of the card and will be covered in another article (here).
The compaq cards are based on the intersil reference design which can be found at the intersil.com website. Other cards also based on this design are, Dlink Wlan, Sitecom, Samsung etc.