What does the AM button in the car mean?

[VonBrooklyn]

The AM button in the car is the band selection button for the car radio. Here is a detailed introduction to the car radio modes: Car radio mode classification: There are two modes for car radios, one is the AM band mode, and the other is the FM frequency modulation mode. Generally, when listening to the radio, car owners use the FM button mode more frequently because FM is used to operate the radio's frequency modulation, while AM is used to adjust the radio's band. Disadvantages of AM band mode: When using the AM band to receive signals, the received audio quality is generally lower. This is because AM uses the medium wave band, and typically, the car AM reception frequency is around 1000KHZ, which results in lower sound volume and less information, leading to poorer audio quality.

[MargaretDella]

Last time a friend asked me about the AM button in the car, I shared my personal experience. Having driven for over 20 years, AM stands for Amplitude Modulation radio, which is different from FM stereo. Back when I took long-distance trips, I loved listening to AM the most—the signals travel exceptionally far, allowing me to catch radio stations hundreds of kilometers away at night. There was something special about listening to live sports broadcasts through the crackling static. Although the sound quality can't match digital radio nowadays, AM proves more reliable in mountainous areas with poor signals. Plus, many local traffic stations still use this frequency.

[StBethany]

Once at the repair shop, I watched a mechanic fix an old radio, and he showed me how the AM circuit works. Simply put, radio stations transmit signals by varying the amplitude of the waves, which is different from FM frequency modulation. This mode is less susceptible to interference from tall buildings, but static noise can be more noticeable during heavy rain. Many new cars still retain the AM button because emergency broadcast systems rely on it to transmit critical disaster warnings, making it far more practical than Bluetooth in emergencies.

[Bradley]

I remember the first time I taught my daughter how to use the car radio. She pointed at the AM button and asked what it was for. I told her it's like selecting TV channels—just press the button to switch to traditional broadcast mode. Many elderly people are accustomed to listening to traffic updates on this frequency, especially during morning and evening rush hours. It's very convenient to switch with just a press while driving, and there's also a corresponding shortcut button on the steering wheel, which is much safer than poking at the screen.