how to fix radio interference from led lights

Table of Contents

What is radio interference?
Why do LED lights cause radio interference?
LED lights radio interference solutions – How to fix?
Radio interference FAQ
- 1. Can LED lights affect WiFi signal?
- 2. Which type of radio signal (AM or FM) – Which is more susceptible to interference?
- 3. Why do LED lights affect my television?
Our conclusion

What is radio interference?

radio-inference-creates-noises Most people who listen to the radio understand that radio signals are transmitted through the air. The signal is picked up by your radio but isn't limited to wireless devices or televisions that receive wireless signals. This interference is added noise that allows you to hear unwanted noises. These noises can be a buzzing, humming, or audible sound that's annoying nonetheless.

Because radio is a transmitted signal, the reason that this interference is happening is a matter you can troubleshoot. You have to look at what is being heard, how often it happens, and other obvious clues. Most of the time, this interference is coming from connected electronic power supplies near your radio. These electronics can even be incorporated among other equipment that contributes to radio interference itself.

In a nutshell, radio signals operate using a specific RF (radio frequency) and this is transmitted between 100kHz to 300GHz. If there is electronic equipment or other transmitters near to your radio, interference can be picked up. As with anything else, RFI (radio frequency interference) can also be caused by other sources. The changes in frequency can be heard when natural elements get involved.

These are primarily solar flares, the electromagnetic disturbance of northern lights, and even lightning during a storm. But not all of these are constant and contribute to an ongoing problem with your radio equipment. The rest of this article will delve into methods on how to determine what is causing RFI and how to minimize and stop it.

Why do LED lights cause radio interference?

LED lights, specifically the ones in your car are often the cause of RFI. But that's not to say other lights that are distributed around your auto are also contributing. New cars that have LED lights added inside and outside the care are all suspect. These can include door lights, illuminating light bars, overhead viewing lights, and interior spotlights. Nearly anything that is running from LED lights in your car can affect radio signals.

But there is also another hidden fact you might not be aware of. LED lights inside your home and your garage can also create a hassle for your wireless devices, mobile phones, and home radio. As shocking as it sounds, LED lights are not the exact cause of the RFI problems. The secret lies with the electronics that power the LED light itself. You may not know this but LED lights run from a series of controlled bursts that are handled through duty cycling.

This means that the number of times the LED will flash per second is managed by the ballast. The Hz ratio that is used for this flicker control is often converted into an electrical signal. It travels through the connecting power cables as a radio signal would and soon reaches a receptive device such as your radio. In your car, the same thing will happen with the LED power supply and you'll hear this through your radio as a result.

There are many reasons why this happens, but one clue is from cheap electronics inside the power supply and specifically the transformer. Now another issue that hasn't been addressed is recessed lighting. The same problem can occur when both the radio and recessed lights are being used. Alternatively, you might have RFI problems with your workbench LED light and radios used next to each other.

led-lights-interfere-with-radio-signal

LED lights radio interference solutions – How to fix?

The first task is getting to be a detective and hunt for a solution. There are all sorts of sensing equipment that you can buy but nothing is better than low-tech devices. For this, all you need is to buy yourself a portable AM radio. It doesn't need to be a fancy one at all but it does need to have volume control and a new battery. What you will need to do is very simple and takes no set-up time at all.

Find a station at the low end of the AM radio dial. Tune the setting so you cannot hear anything being transmitted and there is no static. This allows the AM frequency to act like a stud finder for anything that is transmitting Hz frequencies. The real fun part comes from taking your radio and waving it like a flashlight all over anything that has LED lights or power supplies.

You'll know you've hit the jackpot when the radio picks-up on the signal and makes a humming or buzzing sound. Now you've located your source of the RFI problem. The next thing is to replace the transformer, the bulb, or the ballast. Now easily bulbs can be switched out with a new replacement, but power supplies are tricky. You'll need to take the power supply to a Lighting repair and have them test it to see which is part is failing.

In a car, the power supply meant for your headlights is not a solution so easy to fix. You either need to replace the light itself if it's a brand that's not high quality. But if you want to make a quick fix that might solve the problem, you'll need Ferrite core clips. Ferrite core clips are special filters against electronic interference. These will clip-over the cable that goes to the power source of a headlight.

Since you'll need to troubleshoot the problem you will need to cover all the lights that are connected. This will include the headlights, brake lights, fog lights, and panel lights. I should mention that this isn't necessary if they're standard incandescent bulbs. Only LED lights can be the cause of this interference. As each cable is shielded properly, the hissing or noise on the radio should start to minimize and reduce.

Until all the interference is gone, it will take some time to track down all the connection wires that are related to LED lights. Ferrite clips are also excellent for adding to other LED lights in your home. If it makes the noise disappear, you may not need to replace the ballast or transformer at all. If this trick doesn't take away the noise completely, you'll need to use your AM radio to track down where the interference is coming from.

Radio interference FAQ

1. Can LED lights affect WiFi signal?

The sad truth of the matter is that LED lights can interfere with your WiFi signal. The reason is that a WiFi signal operates at 2.4-5GHz whereas LED lights operate at a higher frequency. This frequency is 400-600THz and is essential electromagnetic radiation. It's not dangerous but it does have the annoying habit of creating electromagnetic waves that are picked up by your WiFi.

This isn't limited to LED light bulbs and fixtures either since putting up LED Christmas lights or decorative accent strip lights too. To minimize this problem, the easiest fix is to attach Ferrite core clips on the wires of LED fixtures. Bulbs can be harder to fix but the best advice is buying a quality brand instead of the cheaper knock-offs.

2. Which type of radio signal (AM or FM) – Which is more susceptible to interference?

both-am-and-fm-radio-signals-are-susceptible-to-led-light-interference Both AM and FM radio signals are affected by radio frequency interference. The one that is more than likely to have more interference is AM radio. This is because AM works from a shorter transmission signal than FM. Since FM signals are much stronger, they can travel on inversion layers of the atmosphere. The interference can sound like hissing, whining, or buzzing noise for both.

With AM radio the sound of music fades away so only a hiss is heard or is unpleasant gargled distortion. Most of the time this issue can be fixed by adding Ferrite core clips to insulate LED wires that are releasing interference.

3. Why do LED lights affect my television?

Even your TV can have interference that comes from LED light bulbs. Either you have to change the light bulb for a quality brand or try to troubleshoot the problem. You can try using EMI filters (electromagnetic interference) such as a Ferrite core filter that shields your TV cables. You might also try shortening the length of the cable that attaches to your TV, as longer bundled cables act like radio reception.

In the case of using an older LED fixture, the ballast inside the power supply may be going bad. This will be another reason why electromagnetic noise is showing-up. You will also see that your LED light is flickering more often or is acting funny. In that case, you'll have to replace the ballast or transformer as a final solution.

Our conclusion

A lot of times the problems that come from LED lights are often from cheap products that aren't 'name brand'. Car headlights that are imported LEDs are always built with cheaper parts in the LED driver and power supply. Aside from having to change faulty parts that are emitting interference the cheapest methods are usually the cheaper route. We hope this article has shed some light on why your radio and other electronic devices are affected by LED light products.