OnAirDecode NOAA Weather Radio SAME with an SDR
NOAA Weather Radio SAME: weather and emergency alerts, decoded and explained (receive only).
- Group
- Weather & science
- Start frequency
- 162.55 MHz
- In the mode list
- Weather alerts, 162.55 MHz
What NOAA Weather Radio SAME is
NOAA Weather Radio broadcasts weather alerts in the US and Canada on seven narrow-FM channels (162.400 to 162.550 MHz). Each alert starts with a SAME (Specific Area Message Encoding) burst that carries the event, the areas and the time.
Frequencies and settings
The seven NFM weather channels, 162.400 / .425 / .450 / .475 / .500 / .525 / .550 MHz (US and Canada), 1 Msps and up.
| Start frequency | 162.55 MHz |
|---|---|
| Tuning range of the mode table | 162.4 to 162.55 MHz |
| Sample rate asked | 2 Msps |
| Lowest working rate | 1 Msps |
| Channel width | 25 kHz |
OnAir takes any frequency you type; the numbers above are the mode's starting point and the range its table describes. In the app the shortcut label is Weather alerts, 162.55 MHz.
What OnAir shows
SAME / EAS alert decoder: 520.83 baud AFSK (mark 2083.3 Hz, space 1562.5 Hz), the header repeats voted bit by bit and every field checked; originator, event with its plain-English name (the full EAS event table), locations with the partial-county direction (NW / N / NE / W / C / E / SW / S / SE), state and province names, valid-for and issue time, sender call sign, how many of the three repeats agreed, the 1050 Hz attention tone, alert history, a state-level map (approximate) and the raw messages. County names only from a county CSV you load (none are built in, see docs/same.md). Receive only: the text of an alert is a public broadcast. Checked on synthetic signals only (no real recording tried yet).
The mode's own tab has these views: Alerts, Map, Raw. The other tabs (Overview, Receiver, Scan, History) are described on the main window page.
Limits and what it was checked with
Checked on synthetic signals only; not verified on a real signal.
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.
Receiving and the law
Questions about NOAA Weather Radio SAME
Can I decode NOAA Weather Radio SAME 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 NOAA Weather Radio SAME?
Receiving these signals is legal in most countries. OnAir is a receiver.
Can I try NOAA Weather Radio SAME 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.