Local-first SDR workbench

Receive locally. Keep control close.

dalSDR is a receive-only SDR workbench for current desktop Chrome, Edge, or Firefox. Choose a local receiver path, view spectrum and waterfall data in the browser, and keep RF, audio, and decoded text on your computer.

Start in three steps

1. Visit the dalSDR workbench.
2. Select Connect receiver, then choose the option that matches your receiver.
3. Follow the next action shown for that option.

Browser support

Chrome and Edge support both the direct RTL-SDR/WebUSB path and the local SoapySDR bridge. Firefox can use the bridge for local spectrum, waterfall, audio, and decoder monitors, but cannot select an RTL-SDR directly. Safari is not a supported receiver browser. The browser, bridge, and receiver must all run on the same computer.

Choose the matching receiver path

For a fuller walkthrough, see Get started with dalSDR.

After you start local spectrum

Use the frequency field to retune. Stop the spectrum before changing sample rate. The direct path reports automatic gain only; bridge gain appears only when the receiver reports a usable range. Choose Enable local audio only when you want to listen.

Then choose a Decoder panel mode. APRS shows only FCS-validated AFSK1200 packets in the current tab. RTTY, CW, and PSK31 are fixed local text prototypes; confirm any copy independently. WSPR reports local four-tone activity only, not stations, messages, or spots. FT4 and FT8 check one complete local 12 kHz slot at a time and show only messages that pass bounded FEC and CRC checks. Results remain in the current tab; they never create a spot, report, or transmission. The Local audio demodulation selector changes browser-side audio only. Receiver-side mode controls and other decoder families are not available.

Privacy and local operation

The bridge is local-first, requires a bearer token, accepts only loopback addresses, and exposes one bounded local IQ-frame path only to the browser on the same computer. Browser-side audio is optional and remains local. It does not expose a network receiver service, upload path, or receiver controls that the selected hardware has not reported. Keep the radio, SDRplay API, SoapySDR, bridge, and browser on the same computer.

dalSDR has no account, analytics, or telemetry path. The workbench uses system fonts rather than contacting a third-party font provider. Its bridge token is kept only in the current browser tab and is not saved.

PSK Reporter forwarding is a future, optional goal; it is not available today. If added, it will require a separate, explicit operator choice before eligible reception decodes and their required report metadata leave this computer.

dalSDR is receive-only. It does not offer transmit, PTT, transmit audio, or transmitter controls.

The local bridge writes limited security events to its terminal (startup, rejected origins, invalid authentication, and temporary limits) without recording bearer tokens, headers, receiver inventory, or serial numbers.

Support information and licenses

dalSDR identifies its supported hardware paths, links to the SDRplay API and SoapySDR requirements, and provides any required license notices. The setup guides explain what each connection option can do today, including the current boundary between local IQ/audio, experimental APRS decoding, and receiver-control features. See Sources and licenses before installing the local SDRplay requirements.