OnAirDecode Signal workbench with an SDR
Signal workbench: analyse, demodulate and read any recording.
- Group
- General & tools
- Start frequency
- 100 MHz
- In the mode list
- Files: audio and IQ
What Signal workbench is
The Signal workbench takes a recording apart without a radio: a spectrogram, measurements, demodulators and the recovered bits.
Frequencies and settings
No radio needed: a recording opened from a file: audio (WAV, MP3, FLAC, OGG, M4A: a real signal, or a stereo file as I/Q) or IQ (.cs8 .cu8 .cf32 .ci16 .cu16, SigMF, IQ WAV).
| Start frequency | 100 MHz |
|---|---|
| Tuning range of the mode table | 0.1 to 6000 MHz |
| Sample rate asked | 2 Msps |
| Lowest working rate | 8 ksps |
| Channel width | 2 MHz |
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 Files: audio and IQ.
What OnAir shows
Waveform and spectrogram with cursors and a time and band selection; peaks, bandwidth (-3 dB, -20 dB, 99 %), carrier offset, SNR, symbol rate, modulation hints, power over time and bursts; AM, FM, SSB, CW, ASK/OOK, 2-FSK / 4-FSK, AFSK (Bell 202, 103 ...), BPSK / QPSK / 8PSK, MSK / GMSK demodulators with eye, constellation and the recovered bit stream (invert, differential, NRZI, Manchester, bit order, pattern search); listening and export.
The mode's own tab has these views: Signal, Measure, Demodulate, Bits, Export. The other tabs (Overview, Receiver, Scan, History) are described on the main window page.
Limits and what it was checked with
This is a tool for looking at the spectrum and recordings, not a decoder of one standard.
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
Tutorials
Questions about Signal workbench
Can I decode Signal workbench 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 Signal workbench?
These tools only look at the spectrum and listen. Receiving is legal in most countries, but laws differ on what you may use the content for.
Can I try Signal workbench 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.