LED lights are an amazing modern-day lighting solution. They consume up to 90% lesser energy as compared to other options (incandescent and fluorescent) and offer better brightness with long working life. However, some users have recently reported problems caused due to LEDs.
And one such problem is radio or TV interference. Some users claimed that after upgrading the car LEDs, they faced disturbance in their AM / FM radio signal. And this somewhat ruined the experience. If you have faced something similar and want a solution, read along.
What is Radio Interference?
Radio signals travel through the air. Whenever you turn your radio on, your car’s antenna picks-up the radio signals and you hear a sound. It’s the reason, in some cases, you might hear those humming or buzzing sounds while your radio is on. And this humming or buzzing sound is what you can call radio interference.
Radio signals use Radio Frequency, which is usually transmitted between 100kHz-300GHz. And if there’s any electronic equipment near your radio that uses the same frequency range, a disturbance can be caused. Most of the time, you’ll hear a buzzing sound / noise, but it’s inaudible sometimes.
Why do LED Lights cause radio interference?
Most of the time, LEDs in your car are the culprits. But that’s not all. Other lights available in the surrounding can be causing the interference too. Recently produced cars come with many LEDs, from main headlights, door lights, overhead lights to illuminating bars and spotlights.
A shocking fact is that the LEDs in your home can also affect the wireless signal, causing radio interference. LED lights are not the main source that causes the problem. It is the device that powers the LED, which causes the disturbance. The power supply of the LED is often called as LED Driver (or sometimes, but rarely, a Ballast).
LEDs work because of a series of controlled bursts of power called Pulse Width Modulation or PWM, which is handled through its duty cycle. The Power to an LED is delivered from a ballast / LED Driver in the form of a series of Pulses, whose frequency will decide how many times the LED will flicker per second.
During this flicker control, the Hz ratio is converted into an electric signal, which is further received by your car radio or other radio devices.
And when this happens, you’ll hear a sound from your radio speaker. Another popular reason behind causing this disturbance is the use of low-quality electronics within the power supply like the transformer.
Yet another issue that causes disturbance is the recessed lighting. When you use the radio and recessed lights at the same time, this issue comes into play. Now, let’s move towards the solutions to these problems.
LED Lights Radio Interference Solution – How to Fix?
Before you move to the solution, you’ll need to find the problem-causing element. And for this, you’ll need sensing equipment. A low-tech portable AM radio will do the job. It’s easily available and is cheap too. However, make sure that it has new batteries and decent volume control.
Once you’re set, you need to find a station on the lower end of the AM dial. Tune it in such a way that you hear nothing and there’s no static. Now, this will act as a stud finder for you. Now you need to wave it all over the devices that use LED lights.
And while waving the AM radio, if you hear some buzzing sound, boom, you found your culprit. Now that you have found the source of the problem, you can replace the transformer, bulb, or ballast. Bulbs can be easy to replace, but you’ll need a professional for internal parts like the transformer. He’ll help you find the part, which is faulty and causing the problem.
Solution for Interference in your Car
First, you need to troubleshoot the problem. And for this, you need to cover all the LED lights which are connected. Examples being brake lights, fog lights, panel lights, and headlights.
If you found a culprit in your car, replacing the internal parts might not be a good option. You’ll either need to replace the faulty LED with a new high-quality one, or you’ll need to go for ferrite core clips. Such clips are special filters that work effectively against electronic radio interference.
The list of Possible Solutions
- You will most probably not face this problem with the new car models with the best quality LED bulbs installed. And if you have an old car or have low-quality LED bulbs, you should replace them with the best quality LED bulbs. There are reputed brands like Philips, Osram that sell compliant bulbs that can minimize your problem.
- Another thing that you can do is install high-quality internal parts in the device that powers the LED. Here, we’re talking about the transformer. You should find a transformer that offers better EMI suppression. Again, you should buy this from a reputed brand.
- You should use wires of short length to prevent any disturbance. You can also use a shielded cable as it is considered as a very effective solution.
- You can use an EMI filter either at the output or input of your transformer. These filters are also known as ferrite chokes or ferrite beads.
Frequently Asked Questions
Ans: Unfortunately, yes. Even though LED lights operate at a higher frequency than the Wi-Fi signals (which operates at a frequency between 2.4GHz – 5GHz), the Wi-Fi Router / equipment can intercept some noise from LEDs.
Ans: Radio interference from LEDs affects both these signals. However, AM radio is more susceptible as compared to FM. It’s because AM uses shorter signal transmission while FM uses a stronger signal.
Ans: Yes, they can. And the solution is fairly simple. Once you find the culprit, in this case the cables which carry signals, you can install ferrite core filters to them. These filters will shield your TV cables that’ll significantly reduce the disturbance.
Ans: Yes. And it’s the most common reason behind the problem of interference. In such cases, you’ll have to purchase a good-quality LED bulb.
In a nutshell, LEDs can significantly ruin your experience whether you’re in your home or your car. It can cause a buzzing/humming sound, which is not pleasing. However, the most common reason behind this is poor-quality parts, which can be replaced all the time.
The hardest part is the troubleshooting. But you can handle that with ease using an AM meter. You can then tweak the settings, find the real culprit and move towards the solution.