[79gmcc15]

if I understand you correctly. you want to have your CB/and radio hooked up to one antenna? you can have as many antennas as you want on a car. as long as the antenna is used for the right purpose. I may be reading your post wrong. IIRC CBs transmit on the AM FREQ. in the low 20MHZ. so you could in theory use your CB antenna for your AM Radio. but it wont work well. but for FM you have to use a antenna tuned to pick up freq. for the FM band and for the freq. range of 88-108 MHz. so what I would do is have 2 antennas. one for your CB and one for your radio. Put one on the drivers side and one on the passenger side. or if you want, have them all on one side. some day, when I get a CB I am going to have my CB hooked up to two antennas one on both side and then have a antenna for my radio. I hope that help in a roundabout way. but wait for other people to chime in.