How to Get Rid of Static Noises On FM Transmitter
The issue is that anything that generates any kind of an electrical field can introduce unwanted noise into your audio system, and there are a lot of different things in your car that generate electrical fields.
Everything from your alternator, to your windshield wiper motor, to the actual components in your sound system, can generate different levels and types of noise and static.
In cases where the noise is only present when your engine is on, and it changes in pitch along with the RPM of the engine, then the problem probably has to do with your alternator. This type of car speaker whine can usually be fixed by installing some kind of noise filter. If the noise is present regardless of whether the engine is running, you’ll want to make note of what audio sources are associated with the noise and move on.
If you only hear the static when listening to the radio, and not when listening to CDs or any auxiliary audio sources, then the problem is either with the antenna, the tuner, or some external source of interference. To determine the source of the interference,
Before you begin, it’s important to note that if you are suffering from a noise that has to do with your antenna, you may want to pay attention to whether the static changes as you drive around. If it only shows up in some places, or it’s worse in some places than others, then the source of the problem is external,
After you have made sure that the problem isn’t external to your vehicle, the next step in finding the source of AM/FM car radio static is to check the head unit’s ground connection.
In other cases, you may find that you hear static regardless of which audio source you select. If you hear the noise when listening to the radio, CD player and auxiliary audio sources, then you could still be dealing with a ground loop problem, or else noise is being introduced somewhere else in the system.
It’s also important to make sure that the head unit is not grounded in the same place as any other component since that can create a ground loop.