OnAirBroadcast radio · Established
Decode FM with an SDR
OnAir receives FM. FM broadcast radio (87.5 - 108 MHz), stereo and RDS.
What FM is
FM broadcast radio (87.5 to 108 MHz in most of the world) carries stereo sound and RDS data such as the station name and radio text.
Frequencies and where it is used
Worldwide.
In OnAir the tuning shortcut is Stereo and RDS; you can enter any frequency your radio reaches.
What OnAir shows for FM
Analogue radio: stereo and RDS (station name, radio text, programme type, traffic flags).
This is one of the established modes, used and tested on real broadcasts.
Which radio you need
Any radio that tunes this range works. An RTL-SDR covers roughly 24 MHz to 1.7 GHz, and every other radio in the radio guide reaches it too. Antenna height and a clear view of the transmitter matter most.
Questions about FM
Can I decode FM with an RTL-SDR?
Usually yes for narrowband signals, as an RTL-SDR tunes roughly 24 MHz to 1.7 GHz at up to about 2.4 Msps. Wide signals such as TV channels need a faster radio, and OnAir says next to the source what the selected radio can do.
Is it legal to receive FM?
Receiving broadcast radio is legal in most countries. OnAir cannot decode encrypted services.
Can I try FM in OnAir without a radio?
Yes. Most modes include a built-in synthetic test signal, so you can open the screen and try the controls before you own a radio.
Try it without a radio
OnAir includes built-in synthetic test signals for most modes, so you can open this screen, see the layout and try the controls before you own a radio. The Tour button walks you through the app.