Like me, some car-owners may have a built-in factory stereo system. What if your car is two to three years old, and your system can’t play mp3s? What options are there to fix this?

The easiest way is to get a mp3 CD-changer, but that costs a lot. Another option is to get a line-in for the system, but it also depends on the car brand, model and year. Not every model has this option and if it does, it will also cost a lot.

Replacing the whole system is also not the best option. You will need to find an aftermarket stereo kit for your dashboard. And why replace it if your factory stereo is doing well?

Some car brands have an iPod interface option. That’s not expensive and you can also use the buttons on your steering wheel to operate the iPod and the stereo can display song titles. But what if you don’t have an iPod and you aren’t an iPod fan?

I used to have an Alpine CD-changer which can play mp3’s in my BMW 3-series. I bought an aftermarket CD-changer interface to connect the Alpine to the BMW stereo (the standard stereo can only use BMW changers). I’ve spent a total of 650 Euros for the whole set. But half a year ago, the changer stopped working and, the warranty was also over, so what could I do?

I don’t have an iPod and the option to build an Aux audio input wasn’t possible, not by the BMW dealer. Finally I saw a gadget called the FM Transmitter.

What is an FM transmitter?

First, you can connect the following devices to an FM transmitter:

-Computer
-Laptop
-PDA
-Navigation systems
-MP3-players
-iPod
-(Portable) DVD-player
-Television

In short, you can connect every device with an earphone input or audio/line-out input. After connecting the device, turn on the transmitter and then, turn your car radio on. Find a free frequency on your radio and also set the same settings for the transmitter. The transmitter will automatically transmit the sound from the connected device in stereo to your car radio or any radio system.

There are also some expensive transmitters which will automatically detect the best free radio frequency and can improve the quality. The differences include the range of the frequencies you can choose from. Cheaper ones can only use a small range of FM frequencies. And of course the transmit distance is also an important factor but most transmitters have a working distance of 10metres.

I’ve bought one for 20euros and connected my mp3-player. I can tell you, it’s working well. Ok, the quality is much lower compared to a wired player, but it’s worth it for that price.
The only thing you have to remember is to turn your mp3 player off when you get out of the car. In the beginning I always forgot it, because you used to start the car and the stereo is working.

At last, it’s not legal in every country to use an FM transmitter. Some countries see this as unauthorized radio use which can cause harmful interference to legitimate users. Before you go to the local electronic store to get an FM transmitter, better find out if it’s legal or not in your country.