How to Make a Phone Work on a Car's FM Radio

In many states hands-free laws now require cell phone users to have a Bluetooth or other hands-free kit installed in their vehicles in order to make calls. Failure to use these hands-free systems can result in fines to anyone caught making calls directly from their phones. In the case that you don't want to install an entire hands-free system you always have the option of using your cell phone in conjunction with your car's stereo system over FM radio frequencies.

Things You'll Need

• FM modulator for cell phones

Instructions

1. Determine what type of audio port your device uses. For instance, most modern Nokia devices now use a 3.5MM audio jack, while older devices use a Nokia Pop Port. In most cases your device will either feature a 2.5MM or 3.5MM audio jack. You can find this information in your device's manual or on most major cell phone specification sites such as GSMArena.com and Phonescoop.com

2. After determining the audio port type your device uses, go online to find an FM transmitter with that audio port connection type. The easiest way to accomplish this is the type the following into Google: "3.5MM FM phone transmitter" or "2.5MM FM phone transmitter" If your device uses a proprietary port, use that device's name in the search.

3. You can also search for transmitters based on the company's name; for instance "Nokia FM Phone Transmitter" returns all types of FM modulators that can be used with Nokia devices. Searching in this manner will give you options specifically designed by your phone's manufacturer, many of which may work better than generic options.

4. Plug your new FM transmitter into your device's audio out jack and tune your radio to the correct FM frequency suggested by the product's instructions. Many products will allow you to set your own frequency. The lower the frequency, in most cases, the less interference you will experience.

5. When you make or receive a call make sure the FM transmitter is plugged into your cell phone. Hit the send key to make or answer a call. If the FM transmitter is on and your radio is tuned to the right frequency, your audio should automatically play through your car's stereo system.

6. To talk back to the person, you'll want to either put your device on speakerphone mode or purchase a stereo-wired headset and clip it to your shirt. These headsets typically offer a small mic located by the clip which can easily pick up your voice, many cell phones also now come with a stereo-wired headset free of charge.

Tips & Warnings

• Using speakerphone mode may cause an echo effect on certain phones, while other phones will stop the other party's voice from broadcasting over the speaker when the FM modulator is plugged in and in use. This is a trial-and-error type of scenario.