does the 2511cd plus ext2 have a built in antenna?
no it requires a clip on or external antenna with pigtail. On the 2511 CD PLUS EXT2 with external antenna leads there is a ‘main’ and ‘aux’ antenna lead. Hold the card with the PCMCIA connector part pointing to the right, the top of the card facing you (with the light on top), the main antenna is the one on the bottom. You only need to attach ONE antenna to this card to have it work properly. The second antenna lead (auxilliary) is only needed if you want to support receive diversity.