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How much does lightning interfere with radio waves, and can we do anything as consumers and radio operators to minimize the effects?
While radio technology might seem relatively simple on the surface, many complex components ensure each type of radio can work effectively.
To access radio content from your AM, FM, DAB, or satellite system, you need a solution capable of converting radio waves into sound.
Radio waves form part of the electromagnetic spectrum. This is also the spectrum involved in the creation of lightning.
Lightning strikes work similarly to radio waves, giving off bursts of energy that radiate across the entire electromagnetic spectrum. It only makes sense, then, that many types of radio waves would be affected by lightning.
Here’s everything you need to know about radio waves, lightning, and the connection between the two phenomena.
The Connection Between Radio Waves and Lightning
We first need to establish how these concepts work to understand the relationship between lightning and radio waves.
Radio waves are a form of electromagnetic radiation best known for supporting communication technologies, such as mobile phones, televisions, and radios.
The radio frequency spectrum, however, is a relatively small part of the electromagnetic spectrum.
Lightning, a natural phenomenon caused by bursts of electronic energy in the atmosphere, also belongs to the EM spectrum.
When lightning strikes, it doesn’t just create electricity; it radiates energy throughout the electromagnetic spectrum.
Particularly, lightning is the most common and powerful natural source of ELF waves – the lowest of all radio frequencies.
Waves produced by lightning can bounce back and forth between the earth and the ionosphere. The ionosphere is the atmospheric layer above the earth with the highest free electrons and ions concentration.
The disturbances in the ionosphere can distort radio signals traveling to satellites.
This is just one of the many ways lightning can influence radio communications.
How Does Lightning Affect Radio Waves?
Aside from interfering with the ionosphere, lightning can also influence radio waves in various ways.
For instance, lightning can create static issues with radio frequencies.
Static interference happens when the electrical discharge of a lightning strike creates electromagnetic fields that disrupt radio signals.
Secondly, lightning can cause physical damage to radio equipment, such as broadcasting towers and antennae.
The high temperatures and electrical currents caused by lightning strikes often damage sensitive electronic components.
Since radio antennas and broadcasting towers often attract lightning in storms, this can be a common problem for many radio channels.
This is why so many companies invest in strategies to help minimize the impact of lightning strikes.
On top of all that, lightning can also create electromagnetic pulses that interfere with radio equipment on a foundational level.
Lightning is a common cause of static interference in the radio landscape. When a bolt of lightning strikes, it creates massive energy.
This energy disrupts radio waves, particularly across specific spectrums, causing radio communications to drop and signals to be lost.
In some cases, lightning strikes and storms can even prevent radio signals from being transmitted.
Does Lightning Interfere with Some Radios More than Others?
The impact lightning has on radio waves can be more significant in certain landscapes than others.
For instance, because lightning strikes can affect the ionosphere, they can sometimes cause disruptions with satellite radio frequencies. Most commonly, problems caused by lightning in the radio space influence AM radio channels.
Light strikes are similar to radio transmitters, giving off specific atmospheric wavelengths. Some frequencies may be affected more than others.
Lightning strikes produce radio waves commonly known as sferics. These cause the static we often hear on AM channels. Lightning’s broad spectrum of radio frequencies generally peaks at around 10Khz.
Notably, the power created by a radio wave decreases as the frequency increases.
This means the energy produced by a lightning strike, even at the lower end of the AM dial, is about 10 times stronger than the power received at the high end.
For this reason, static from lightning strikes is generally more noticeable at the lower end of the AM band.
In frequency-modulated radio or FM channels, the frequencies are much higher. This means it’s less common to see a problem with an FM station caused by a lightning strike.
Can You Reduce the Influence of Lightning on Radio Waves?
Lightning is a natural and unpredictable phenomenon that can occur for various reasons worldwide.
Because of this, it can be challenging to control the impact lightning effectively has on radio waves. However, researchers have experimented with multiple methods of reducing lightning interference in the radio landscape.
For instance, many broadcasting towers potentially influenced by lightning use specialist antennas designed to reduce interference. Measures are also implemented to minimize the damage caused by lightning strikes to radio equipment.
Lightning can damage various aspects of a radio system, from the radio to the power supply and the coaxial cable.
A lightning arrestor, a special device placed between the radio and antenna, can sometimes intercept the lightning strike and dissipate excess energy.
Broadcasters can also use surgery protectors between the power supply and the radio to absorb the electrical energy from the lightning and protect radio equipment.
Another common strategy is to use careful grounding methods. Antenna grounding ensures a path for an electrical current from a lightning strike to follow. This guides the electrical current into the ground, instead of the radio equipment, to protect the components.
Innovators in the radio world are also exploring ways of minimizing the EMPs or electromagnetic pulses from lightning strikes, which can influence radio equipment performance.
Proper shielding techniques can reduce the impact of EMPs, and allow radio equipment to continue functioning.
Can Radio Equipment Survive A Direct Lightning Strike?
As mentioned above, one of the most significant ways lightning directly influences radio equipment and broadcasts is by damaging the radio equipment.
Some forms of radio equipment may be more resistant to damage than others.
For instance, a handheld radio may be less likely to be damaged by lightning strikes than a standard base station radio.
However, lightning’s electrical and thermal energy can be enough to destroy even the most resilient radio equipment.
This is one of the reasons professionals in the broadcasting landscape take extra measures to protect radio equipment from lightning damage.
As thunderstorms become more common during certain seasons, some professionals will disconnect antennas and external connections during a storm.
Others will implement careful strategies and technologies designed to keep radio systems operational.
If you’re listening to the radio during a storm, it’s usually a good idea to unplug equipment and disconnect it from any power sources. This can reduce the potential damage caused by a lightning strike.
Lightning and Radio Waves
Ultimately, lightning can cause more disruptions than most people realize. Lightning is one of the most dangerous weather phenomena for any radio equipment.
A single lightning strike can harm radio waves, destroy electronic equipment, and cause significant issues.
This is why it’s so crucial for operators of radio equipment to take extra steps to protect their equipment and prepare for expected storms.