Broadcasting FM radio from your computer offers a spectrum from simplicity to expense. Here, I unveil two budget-friendly methods to transfer your music from your computer to your FM radio.
Steps

Identify your target audience. If you're in the USA, the FCC has specific regulations governing transmission power for broadcasting.

For broadcasting to your home stereo or a backyard boombox, consider purchasing an MP3 FM radio transmitter.

Connect the MP3 FM radio transmitter to a speaker or headphone jack on your computer.

Load a playlist onto Windows Media Player or another media player app, then hit play.

Now, relax and enjoy your favorite tunes.
Consider Utilizing a PCI Card

Opt for an FM transmitter that plugs into a PCI slot in your PC.

Link the jumper cable from your PC's speaker out/headphone jack to the transmitter's audio input.

Install the provided software.

Select an available frequency for transmission.

Load your preferred playlist into any media player software, then hit play.

Now, indulge in your favorite tunes.
Helpful Tips
- To announce songs, enable your microphone playback by unchecking the mute checkbox on your PC soundcard mixer.
- Utilize Skype for telephone call-ins during broadcasts.
- Consider accepting song requests via email from friends and neighbors.
Important Warnings
- In the USA, using an FM transmitter not compliant with part 15 rules requires a license. While the methods mentioned are legal, there are stronger transmitters available that require licensing. Ignoring this could lead to costly consequences.
- Refer to https://www.fcc.gov/media/radio/lpfm for information on obtaining a Low Power FM license.
Essential Tools
- an MP3 FM transmitter or
- a PCI MAX 2007+ FM transmitter
- Media player software
- Optional: Skype-in account
- Optional: Microphone
