True - in teh portables, the antenna IS the reciever, and the subscription goes with it. In teh G3X, the antenna is just an antenna - the reciever is built into the display unit. The antenna/reciever for the 396/496 is a GXM 30, and for the 696/796 a GXM40....they are different dimesnions, but I don't know if they are software compatable.