• SDR
  • Beginner
  • 5 min
  • Serial CLI + Web ESP SDR

Recipe · Beginner · SDR, USB

How to use the ESP SDR USB adapter

Use the ESP32-S3 radio as a USB SDR source for the browser spectrum viewer.

USB adapter and host-tool workflow.
The dedicated adapter connects the ESP32-S3 radio to a host tool through native USB.
Step 1

Start the SDR adapter

Switch to USB mode and open Adapters:

mode usb
adapters

Select ESP-SDR Raw 2.4GHz. The board reboots into SDR mode.

Step 2

Open the spectrum viewer

Close the terminal, open Web ESP SDR and click Connect. Select the board’s USB port.

In Live SDR, set a center frequency, such as 2437 MHz, then click Start stream.

Step 3

Return to the CLI

Click Stop, then Disconnect. Reset the board and reopen the terminal. Select the SDR adapter again for the next session.

Result

What success looks like

The spectrum and waterfall update with RF activity. Resetting the board returns to the normal Bit Pirate CLI.

Troubleshooting

  • No SDR entry: Use ESP32-S3 firmware that includes the SDR adapter.
  • Port busy or missing: Close other serial clients and check the native USB cable. After a reset, select SDR again.
  • Little activity: Check the antenna and tune to a nearby active 2.4 GHz device.

ESP SDR FAQ

Do I need an external radio module?

No. SDR uses the ESP32-S3 radio and antenna; no GPIO wiring is needed.

Does Disconnect return to the CLI?

No. It releases the browser’s serial port. Reset the board to leave adapter mode.

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