Capture & replay a 433 MHz signal

The EMWaver Air's CC1101 radio can record an on-off-keyed (OOK) signal — a keyfob, a remote socket, a doorbell — inspect the waveform, and retransmit it. This all runs in the browser with your Air paired.

What you need

• An EMWaver Air, powered on and paired in the browser (it shows connected).
• A 433 MHz OOK source to capture — e.g. a remote socket or simple keyfob.

Steps

1. Open the radio script. Run cc1101.emw on emwaver.ai. The script renders its controls and a live signal plot.
2. Initialize the radio. Hit Initialize to bring up the CC1101 at 433.92 MHz in OOK mode. (This reads the radio's registers, so it takes a moment over the relay.)
3. Record. Press Record, then trigger your remote close to the Air. You'll see the burst drawn on the plot; the on-board white LED follows the radio's data line, so activity is visible on the board too.
4. Stop & inspect. Stop the capture and zoom the waveform to check you caught the full packet. The samples are buffered host-side, not on the device.
5. Retransmit. Press Retransmit to clock the capture back out through the radio. The Air owns the microsecond timing locally, so the replay is faithful even over the network.
6. Save the session to come back to the capture later.

How it works

Capture streams the radio's GDO0 data line to the browser in bounded windows; replay streams it back to a device-side ring buffer that an RMT/DMA-clocked loop plays out. You never load a whole signal into device RAM, and network jitter never sits in the timing path.

If you need to recover or reflash the board first, see Flash or recover over Web Serial.