antenna help

hey i just bought a 94 bmw 318is. the person before me put in a new cd player and now i cant get any radio stations. can someone tell me where the antenna is, i assume in the back window(not in the manual) and how i can fix this. should i take out the cd player and make sure the antenna is plugged in the back of it or what. any help is appreciated.

Check the back of the head unit... there should be a black coaxal cable plugged into it that is the antenna.