Who’s on the band?
Plug a software-defined radio dongle into this computer and let it watch a band. It learns the normal noise floor and regular signals, flags anything new or unusual, and keeps a waterfall history you can scroll back through. It only measures signal strength; it never decodes what anyone says.
What to watch
Spectrum and waterfall
Live: newest sweep at the top. Grey dashed line is the learned quiet level; red is the flag threshold.
Signals flagged
| Frequency | Started | Lasted | Strength | Width |
|---|
“New” means nothing has shown up on that frequency in this range before. Signals that come and go regularly, such as a busy repeater, stop being flagged as new once learned.
Noise floor over time
Median level across the range, one point a minute, in decibels relative to the dongle’s full scale. A rise that does not go away usually means a new noise source nearby: a power supply, charger, LED lights or a solar inverter.