How does an AM radio work

How does an AM radio work

Many people do not really know what radios are and how do they work. Our job here today is to change that and tell you all of the basic information that you need to know about AM radio.

Basically, AM radios use a certain approach to radio signals, collect them and transform them into audio signals. That is how AM radios work, in short terms. But, you will find out more in the continuation.

Today, we will be discussing several other topics as well. You will be learning about certain parts of AM radios, how do they work, do people still use them, and what is their history. So, stay tuned, and let’s begin!

What is an AM radio?

If you have ever wondered what does AM stands for it actually means “Amplitude Modulation”. In other words, this means that certain AM signals are able to change their amplitude in order to adapt to certain information through the wavelengths. AM radios are devices that are able to pick up those Amplitude Modulations and convert them to sound information.

To be more precise, AM signals are those signals whose amplitudes can vary and are reflecting in their wavelengths. Read more about What is AM radio.

0070580588.01. SCLZZZZZZZ SX500

How do AM radios work?

The process of how AM signals are being converted into sounds might be hard to explain, but, we will try our best!

A very simple AM receiver is able to receive strong AM signals. Let’s say that you have a basic AM radio somewhere in your home. As soon as you turn it on and tune it to a certain radio station frequency, the transmitter will start transmitting that frequency.

Certainly, all AM radios are obligated to have an external (or a small internal) antenna in order to pick up signals. You won’t need an antenna unless you are sitting right next to the signal source.

As you well know, AM radios have tuners. If the tuner is not present, your radio will be receiving hundreds of signals waves. A tuner is needed in order to choose just the one signal between those hundreds. The way tuners work is very complicated, but, it’s important to know that they use resonance. Resonance is, in a way, a principle used to amplify certain frequencies, while being able to completely ignore some other.

And lastly, once the signal has been singled out from the rest, your radio will be using a detector with a diode. This detector’s job is to not allow the signal to flow both ways- it gives the signal ability to flow in only one direction.

After the detector has done its job, the amplifier takes the lead by sending the sound to the speakers. And that is how you can hear your favorite songs on the radio if you tune into an AM radio station.

amplitude modulation: How does an AM radio work
Photo: physics-and-radio-electronics

So, to summarize all of this, these are the components that any AM radio needs to have in order to work properly:

  • An antenna
  • A tuner
  • A detector or a demodulator with a diode
  • An amplifier
  • The speakers

Digital AM radios are a little bit different than the analog ones. You will probably also stumble upon some AM radios with both digital and manual tuning features. But, digital AM radios usually do not have tuners or tuning knobs. Since they can automatically detect the best, and strongest AM signals, you will be able to simply turn the radio on and listen!

AM Broadcasts

There are over six thousand AM radio stations in the US right now. All of them could be accessed. Some are made for entertainment purposes, while others exist to inform people about certain happenings. Either way, AM radio stations are still being listened to frequently. Of course, FM radio stations might be in use more than AM ones, but the broadcasts are still there.

If you have been wondering where, or how to find the full list of available AM radio networks, do not worry we have your back. We have been able to find one website that contains all of the information about the broadcasts you might need. By clicking here, you will be taken to the website made by US citizens that contains over 500 radio stations.

On the other hand, if you know your way around technology, and are using smartphones every day, there is another way to find the nearest AM radio stations. You can simply take your smartphone, go to the App Store, search for AM radio stations, and download any application that you might like. There are dozens of apps available that will give you frequent notifications about new broadcasts.

Some radio stations even have their own online broadcasting platforms. Just by searching your favorite AM radio station, you will be able to tune into it from a PC. This clearly makes things easier for people without an AM radio!

Related: How to improve AM radio reception in the Car

The conclusion

The history of AM radios is huge. And, the impact AM radios have had on the society is major. If there weren’t for AM radios, who knows what would have happened with technology today. There probably would not be as many high-tech devices available to us.

The discovery of AM radio signals let to other major discoveries. FM radios have been discovered right after AM ones, and just look at their impact today!

On the other hand, we hope that you were able to understand how AM radios work. The best thing about all of this is that you are even able to make your own simple AM device just by gathering all of the components and connecting them together. This might be a good experiment if that’s what you enjoy doing!

How does an AM radio work


  1. When was the first radio broadcast?

The first-ever broadcast was in the year 1920 on the 31st of August. The broadcast happened in Detroit, Michigan, and was made by the 8Mk radio station.

  1. When was the birth of public radio broadcasting?

Unlike the first radio station broadcast, the first-ever public radio broadcast occurred ten years earlier. The birth of public radio broadcasting happened in 1910 in New York City. It was an entertaining broadcast featuring many popular metropolitan Opera stars.

  1. What was the first AM radio station in the world?

The first radio station in the world was the KDKA radio station which began the broadcast back in 1920 in Pittsburgh.

  1. What does AM stand for?

AM stands for “Amplitude Modulation”. We have previously explained that amplitude modulation means that amplitudes change their wavelength.

  1. How to find the list of AM radio stations near me.

In order to find the list of AM radio stations in your area, you will need to know your city’s ZIP code. This website HERE is able to give you the full list of AM broadcasts in your area once you enter your ZIP code. The radio-locator website will also be able to give you information about FM radio stations in your area, as well as some more information about them.


Enjoy this blog? Please spread the word :)

Scroll to Top