br br How to use fm transmitter for iPhone in Older Car Radio. br br If you have a car that is more than 5 years old. Chances are, it will not be compatible with your new iPhone 6. br br FM Transmitter for iPhone provides a simple and effective way to connect your new iPhone 6 to your older car factory radio without Bluetooth or Aux input. br br It is extremely simple to use this fm transmitter for iPhone in your older car radio. Simply connect this fm transmitter for iPhone to your iPhone 6 and set your radio preset to 89.9 and you are ready to stream music and talk handsfree thru your older car radio.