[Mike] takes us through the process of adding  a removable high gain antenna to the WRTSL54GS in this article. The antenna that comes on this unit from the factory is a bit small and underpowered. After upgrading it using OpenWrt, an open source full featured router software package, he felt it needed a beefier antenna. So, he cracked it open. The new antenna can simply be soldered in place, where the old antenna was.