FM transmitter could be a great, inexpensive way to breathe new life into a failing car audio system. because they are very easy to use. Rather than upgrading your head unit or installing expensive hardware such as an FM modulator, an FM transmitter opens up a whole new world of listening possibilities at a relatively low cost and with almost no effort.
The problem is that FM transmitters are not reliable and do not always work correctly. If you’re trying to use an FM transmitter in your car and you’re mostly hearing static or interference from real radio stations, we’ve got five tips to help you improve your listening experience.
Why choose an FM transmitter?
When MP3 players were first introduced, they represented a huge change in the way people listened to music in their cars. If you invested in an MP3 player, even with that day’s storage restrictions, you could suddenly bring hundreds or thousands of songs with you without fiddling with dozens of cassettes or CDs.
With the massive adoption of smartphones all over the world, you don’t even need a dedicated smartphone. If you have an iPhone or Android, you also have an MP3 player and the ability to listen to internet radio in your car. The problem is that older car radios don’t always include a way to connect a phone or MP3 player, which includes FM transmitters.
While there are several ways to connect your phone to your car’s head unit, FM transmitters is the cheapest and easiest way to do it. Instead of creating a permanent wired connection, an FM transmitter essentially creates a personal radio station that broadcasts wirelessly to the radio in your car’s head unit.
If you are already using this FM transmitter but are not satisfied with the sound quality, check out these five tips to smooth things over:
Know what features to look for: research before you buy
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The key to getting the most out of the FM transmitter in your car is to start with a decent product first. While most FM transmitters are affordable, there are some pretty important features to look out for. Cheap at the cost of features and you’re asking for a bad listening experience.
The most important feature to look for is manual tuning, as this is the one that avoids interference from local radio stations. Some transmitters allow you to select only a few preset frequencies, while others do not allow you to change the broadcast frequency at all. Pick one of these FM transmitters and you’re stuck with what they give you.
Input Options is another extremely important feature to look out for. Most transmitters come with a standard audio jack that you can plug directly into your MP3 player’s line or headphone output, but you can also find transmitters with USB connection SD card slots and more.
Some transmitters can even play music from USB drive or SD card without the need for a separate MP3 player. All of these features provide excellent sound for a simple audio jack.
Set the right frequency: start from the end

When you take your FM transmitter out of the box, the first thing you need to do is tune it and your head unit to the same frequency.
If the transmitter allows you to select FM frequency then you can start by checking the extremes of the FM band. In these places you are most likely to find free space.
While you can find an available frequency anywhere, the most commonly exposed areas of the FM band are below 90MHz and above 107MHz. There are stations in some areas that broadcast between 87.9 and 90 MHz and between 107 MHz and 107.9 MHz, but these are still the easiest and best places to start.
Try Other Frequencies: Avoid Interference from Bad Neighbors
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While searching for an empty frequency is mandatory, you may still experience interference if a powerful station is using a nearby frequency.
For example, you will find that the frequency of 87.9 MHz is free and clear, but there are still problems with interference. This type of interference is usually caused by a station that is so close or so powerful that it spills over into adjacent frequencies.
For example, there might be a station nearby using 88.1 MHz that is so powerful that it gives the impression of being on 87.9 MHz.
To avoid interference of this type , try to find an empty spot on the dial that has nearby stations that are at least 0.2 MHz up and down. If you can’t find that big block, which is quite possible in many large metropolitan areas, experiment to find the block with the least amount of interference.
Using External Resources: Look for Empty Bandwidth

The radio waves are crowded, but FM transmitter companies are interested in customer satisfaction. To this end, some of them maintain lists of FM stations by geographic region, and some even have tools that you can use to identify the least busy part of the FM band in your area.
You can also do the same research yourself, but it’s much easier to use these tools if they’re available for your geographic area. Some potentially helpful lists and tools include:
- Radio-Locator.com
- SiriusXM FM Channel Finder
While these and similar tools are useful, you may find that the real world doesn’t match their offerings. The problem is that most of these tools are based on databases FCC and the information they receive may differ significantly from the actual conditions.
So while you can start with a station finder tool or even an app that performs the same function, you will never get better results than doing the job and looking for clear frequencies yourself.
Tear It All Down: Should You Use an FM Transmitter at All?
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Sometimes nothing you do works. The hard reality is that if you live in a major metropolitan area, the radio discs may be too crowded to use the FM transmitter effectively. In this case, all you can do is tear everything down and start from the beginning.
If you live in an area with a particularly crowded FM landscape, then there’s a chance the FM transmitter won’t be able to cut it. Try the search tools in the previous tip first. If it says the entire FM band is full, you could save yourself some money and frustration by simply switching in the other direction.
Is this direction FM modulator a new head unit, or physically removing your antenna so those nasty radios don’t interfere with your transmitter, it’s up to you.