Site Owner & Radio Enthusiast
LED lighting has been an incredible addition to the modern world for many consumers. In fact, in a previous life, I owned a commercial energy-efficient lighting company for seven years, in part due to believing in the tech and the environmental and energy savings so much.
The bulbs consume up to 90 percent less energy than incandescent and fluorescent alternatives, making them ideal for reducing energy costs (and your impact on the environment)
Plus, most LED lights can offer exceptional brightness, long-lasting durability, and other great benefits, all for a minimal cost.
The only problem is that LED lighting can sometimes also cause issues with the transmission of radio waves. This means they interfere with radio and TV connections.
If you’ve recently updated the lights in your home or car, you may have faced problems with your AM, FM, and DAB signals, such as hissing or dropped audio.
So, what’s the reason for this, and what can you do about the problem?
What Is Radio Interference? An Introduction
To understand why LED radio interference is a problem, we first need to understand what radio interference is.
As you may already know, radios are powered by radio waves, which travel through the air invisibly, broadcast by stations around the globe.
When you turn your radio on, your system’s antenna picks up those signals. It converts them into sound emitted through your speakers.
However, if electronic equipment or other items around your radio use the same frequencies as the radio waves you’re collecting, this can cause a disturbance.
This is known as radio interference.
There are a few main types of radio interference worth noting:
- Transmitter interference: Communication systems transmitting signals like amateur radios, CBs, and various other radio stations can suffer from transmission problems. Frayed wires, insufficient filtering, and inadequate shielding cause these. With this issue, the problem is related to the radio technology itself, not any surrounding products.
- Electrical interference: Electrical interference happens when electrical signals interfere with the signal supplied to AM and FM radio. If your device emits a buzzing noise, hiss, or whining sound, this could indicate electrical interference.
- Multi-path interference: FM signals are often affected when part of a signal is obtained from a transmitter when a large object or building reflects another element. AM multi-path interference happens when the changing ionosphere of the world during morning and night causes the audio to drop in and out, creating distortion.
- RF interference: Radio frequency interference is caused when transmitters issue a similar or the same frequency as the one you’re receiving. For instance, baby monitors, cordless phones, and amplifiers can all cause interference.
Why Do LED Lights Cause Radio Interference?
The fact that low-voltage LED lights can sometimes cause interference with AM, FM, and DAB signals might be a little confusing.
After all, LEDs don’t submit radio waves.
If you’re suffering from LED light radio interference, the problem probably isn’t the light itself but the device that powers the LED.
The power supply of an LED light, often called an LED driver or ballast, can cause disruptions to wireless signals.
The issue is often common in cars, but other lights can cause interference in the home and different environments too.
Some radio systems are influenced by surrounding LED lights, from headlights to overhead lamps and spotlights.
LED lights work using a series of controlled power bursts known as pulse width modulation or PWM.
The power of the LED is delivered from the LED driver in a series of pulses, which form a frequency defining how many times the light will flicker per second.
The HZ ratio of the flicker is converted into an electrical signal, which can then be picked up by a car radio or other radio-operated devices.
When your radio picks up this signal, you hear a sound from your speaker, usually a buzzing or whining noise.
How to Fix LED Radio Interference
Radio interference caused by LED lighting can be frustrating, but it can also be easy to fix.
The first step you’ll need to take is to define the source of the interference. You can do this quickly if you already have a low-tech AM radio.
All you need to do is find a station on the lower end of the AM dial. Make sure you tune it so you hear nothing but silence.
Next, move your radio close to all the devices using LED lights. You’ve found the culprit if a buzzing sound emanates from the speaker.
You have a few options for how you can fix the problem. One option might be replacing the LED light’s transformer, bulb, or ballast.
This can be simple enough if you’re replacing a bulb, but you might need professional help with other changes.
You can also try these solutions.
Using Ferrite Cores
Ferrite cores are one of the simplest ways to solve an LED radio interference problem. They’re available for a relatively low cost, but installing them on inaccessible lights can be a little tricky.
If you’re struggling, you can choose ferrite beads or chokes and wrap them around the cables that power your lights to create an interference block.
The biggest issue with this method is you will need a different ferrite solution for every bulb.
However, once you install these cores, you should notice that the interference diminishes.
The ferrite structure will block high-frequency currents so that you can enjoy better audio.
Replacing Your LED Lights
Sometimes, the best way to fix an LED radio interference problem is to upgrade your LED lights.
Many modern LED lights are designed with integrated ferrite elements to minimize the risk of interference. If using a ferrite core on indoor lighting and other equipment is complex, switching to higher-quality lighting could be a more straightforward solution.
Look for LED lights sold by reputable companies that comply with EMI regulations.
You can even check out reviews from other customers to see whether they’ve encountered any problems with radio signal interference before buying.
Changing the LED Lamp Transformer
In many issues with LED light interference, transformers are often the source of the problem.
Replacing the transformer in your fixture with one designed to suppress electromagnetic interference eliminates the need for a ferrite core.
Generally, this is only an option with low-voltage LED light fixtures.
With anything above 12V, you’ll be better off using the other methods mentioned in this article.
Additionally, it’s worth remembering that some LED light systems can make it difficult to access the transformer.
Switch Your Cables
While this solution doesn’t completely eliminate the problems caused by all LED light sources, it could reduce your risk of interference.
Longer cables are more likely to be exposed to interference than shorter wires.
If it’s possible, switching to a shorter cable could be a good option.
Of course, this might not be something you can do if the source of your interference comes from an internal bulb within your car or a light in your home.
Dealing with LED Light Interference
Unfortunately, LED lights can cause radio interference, mainly if you use lower-quality lights without integrated protection.
However, there are ways to fix the issue if you find interference is causing your audio quality to drop.
Plus, as radio technology continues to evolve alongside LED lighting, there’s a good chance manufacturers will begin to take additional measures to protect against interference.
Already, high-end LED lights are designed to minimize electromagnetic disturbances.
Can LED Lights Affect Other Signals?
Unfortunately, LED lights can affect several wireless signals around your home and in your care.
In some cases, they may cause interference with your Wi-Fi signal or router. LED lighting could cause interference on your television.
Is AM or FM More Susceptible to LED Interference?
Radio interference from LED lights can sometimes affect AM, FM, and DAB signals.
However, because AM uses shorter transmission signals, AM radios are often more susceptible to various forms of disturbance.
Are Cheap LEDs More Likely to Cause Interference?
Cheaper LEDs are most likely to cause interference because they’re typically not designed with technology that can help minimize electromagnetic disturbances.
Upgrading to a higher-quality LED bulb could be one of the easiest ways to fix interference issues.