For anyone reading this, this might be true on a Volvo but is not true on an LT. My LT has a separate antenna for the AMFM radio, the dual antennas are dedicated CB antennas.
on a volvo uses BOTH antennas for the cb AND am/fm radio AND tv... also if your phone has a external antenna plug it can also be hooked up to the sticks On the prostar they have a separate am/fm antenna (like a car) and both cb antennas are deadacated to just the cb....