Will a 802.11a/b/g Wireless LAN mini PCI card receive a signal without an antenna?

Answer 1

Well, yes but only at a very close range! If this happens to be a high powered card it can be damaged by having no antenna! Just remember to work, they have to transmit too! That is where the issue really gets problematic! The transmitters don't like sending with no antenna - they overheat!
(By short range I mean a few feet! Usually just far enough to let you set it up etc but not far enough to use for much!)