Connect an SDRplay RSP1A or RSP1B

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Use this guide only for an SDRplay RSP1A or RSP1B. You do not install dalSDR, clone its repository, or run a local web server. The radio, its SDRplay software, the small local bridge, and your browser stay on the same computer.

Choose the browser before setup

Use current desktop Chrome or Edge for this guide. Safari and Firefox are not supported receiver browsers. This is separate from the RTL-SDR/WebUSB path, which is also Chrome/Edge only.

First, run the bridge

Quit any other SDR program and connect the receiver directly to USB. The RSP1A and RSP1B use this local bridge, not the RTL-SDR/WebUSB option. It listens only on this computer and requires a token; it is not a network receiver service.

Run exactly one command for your operating system. No folders, tokens, or environment commands are needed: the launcher checks the prepared local runtime, creates a fresh local token, downloads the bridge script to a normal local application folder, and keeps the bridge running. It replaces a prior dalSDR bridge itself, but never stops a different local application using the same port. If it says that local requirements are not ready, use the one-time setup for your operating system below, then run this same command again.

Choose your operating system. Run its command once, then leave that terminal window open after it starts.

Windows 10 or 11

In PowerShell, run this one command.

Source: inspect the Windows launch script.

powershell -ExecutionPolicy Bypass -Command "irm https://mb243.github.io/dalsdr/bridge/run-windows-sdrplay.ps1 | iex"

macOS

In Terminal, run this one command.

Source: inspect the macOS launch script.

curl --proto '=https' --tlsv1.2 -fsSL https://mb243.github.io/dalsdr/bridge/run-macos-sdrplay.sh | bash

Linux

In a terminal, run this one command.

Source: inspect the Linux launch script.

curl --proto '=https' --tlsv1.2 -fsSL https://mb243.github.io/dalsdr/bridge/run-linux-sdrplay.sh | bash

The source links show each small launcher before you run it.

Connect the bridge in your browser

These steps are the same on Windows, macOS, and Linux. Copy the displayed token and leave the bridge window open. Its startup line should include local_iq_frames=true.

Now open sdr.kf2em.com in a desktop browser:

Select Connect receiver → Local SoapySDR bridge.
Leave the local address unchanged, paste the token, and select Discover devices.
Select your receiver, then select Start local spectrum.

If no receiver is listed, use the one-time setup for your operating system below, then run the same bridge command again. The browser stops a stalled vendor discovery after a short bounded check, so it is the safe readiness check.

If you want to listen, select Enable local audio after the spectrum starts.

The spectrum and waterfall now receive local IQ frames. Local audio is optional and stays on this computer. Use the frequency field to retune the active receiver; select Stop local spectrum before changing sample rate. If Receiver gain appears, its range and current value come from the selected receiver; adjust it only when needed.

With the spectrum running, the APRS panel can show FCS-validated AFSK1200 packets even when audio is muted. Packets appear only in the current tab, clear when the spectrum stops, and are not saved or sent. The APRS decoder has synthetic-signal coverage; on-air receiver validation is still pending. RTTY is an experimental fixed 2125/2295 Hz, 45.45 baud local text prototype: copy appears only after start/stop framing checks and should be confirmed independently. CW is an experimental fixed 700 Hz, 100 ms-dot local Morse prototype: copy appears only after timing checks and should be confirmed independently. PSK31 is an experimental fixed 1000 Hz, 31.25 baud BPSK/Varicode local text prototype: copy appears only after framing checks and should be confirmed independently. WSPR monitors local four-tone activity near 1500 Hz; it does not decode stations or messages, or report spots. Mode controls and other decoders are not available through this connection yet.

The Sample loss field reports receiver overflow events when the driver reports them. None reported means the bridge has not received an overflow event; it cannot prove that no sample was missed.

One-time setup, only if the bridge cannot discover the receiver

Use this section only when the bridge says its local requirements are not ready or Discover devices does not list the connected receiver. Start by installing the current SDRplay API for your operating system from the SDRplay API download page. Do not run another SDR application at the same time. SoapySDR itself also needs the SDRplay module; installing only the SDRplay API or SoapySDR core is not enough.

There is not yet a signed, one-click bridge installer. The following setup builds the missing SoapySDR module in its own dalsdr-bridge environment. It does not install the dalSDR web app.

Windows 10 or 11: one-time setup

Install the 64-bit SDRplay API 3.15, accept its license, and restart if asked. Connect the receiver directly to USB after installation.
Install current 64-bit Miniforge and Microsoft Visual Studio Build Tools with Desktop development with C++.
The Windows setup-script source creates the isolated bridge environment and builds the SDRplay module locally; it is safe to rerun after an interrupted setup.

In x64 Native Tools Command Prompt for VS 2022, run this one command:

powershell -ExecutionPolicy Bypass -Command "irm https://mb243.github.io/dalsdr/bridge/setup-windows-sdrplay.ps1 | iex"

Run the single Windows bridge command above. The launch script selects dalsdr-bridge for you. Then use Discover devices in the browser.

macOS: one-time setup

Install the macOS SDRplay API and approve it in System Settings → Privacy & Security if asked. Connect the receiver directly to USB.
Install Homebrew if needed. The macOS setup-script source installs Homebrew packages, builds the SDRplay SoapySDR module in your user-local bridge folder, and changes no vendor API files.

Run the one-time setup:

curl --proto '=https' --tlsv1.2 -fsSL https://mb243.github.io/dalsdr/bridge/setup-macos-sdrplay.sh | bash

The SDRplay API 3.15 installer places its headers and library under /Library/SDRplayAPI/3.15.1; the setup script uses that documented location. If your installed API uses another version, use the source link above to adapt the setup before running it. Then run the single macOS bridge command above and use Discover devices in the browser.

Linux: one-time setup

This setup script supports Ubuntu LTS and other apt-based systems, which matches the Linux platforms SDRplay tests for its API. Install the Linux SDRplay API 3.15. For its downloaded installer, substitute the actual filename:
```
chmod +x SDRplay_RSP_API-Linux-*.run
sudo ./SDRplay_RSP_API-Linux-*.run
```
Install Miniforge, then open a new terminal.
The Linux setup-script source installs the compiler toolchain, creates the isolated bridge environment, and builds the SDRplay module locally; it is safe to rerun after an interrupted setup.

Run this one command:

curl --proto '=https' --tlsv1.2 -fsSL https://mb243.github.io/dalsdr/bridge/setup-linux-sdrplay.sh | bash

Run the single Linux bridge command above. Then use Discover devices in the browser. If the device is not listed, close other SDR programs, reconnect it, and open a fresh terminal. On a USB permission error, sign out and back in.

If something goes wrong

What you see	Next action
The bridge says local requirements are not ready	Complete the one-time setup for your operating system, then run the same one-command launcher again.
No receiver is listed	Quit other SDR programs, reconnect directly (not through an unpowered hub), restart the bridge, then select Discover devices again.
Safari or Firefox is used for a receiver connection	Use current desktop Chrome or Edge. Safari and Firefox are not supported receiver browsers.
The bridge says local receiver discovery did not respond	The bridge stops a stalled vendor probe after a short bounded check. Close other SDR programs, reconnect the receiver, restart the bridge, then select Discover devices again.
Browser says the local bridge needs an update	Run the same one-command launcher again, then paste its new token. It downloads the current bridge and replaces a prior dalSDR bridge itself.
The launcher says port 8091 is used by another app	Close that other app, then run the launcher again. It replaces only a prior dalSDR bridge.
The bridge says NumPy or SoapySDR is missing	Rerun the one-time setup for your operating system; the launch script selects the prepared environment. On macOS, rerun `brew install soapysdr numpy`, then restart the bridge.
Browser says the bridge is unavailable	Leave its terminal window running and use the unchanged local address.
Browser gets `401` or `429`	Restart the bridge to create a new token, paste it exactly, and wait one minute after repeated unsuccessful attempts.
Local spectrum stops	Check the bridge window and USB cable, close other SDR programs, rediscover the receiver, then start the spectrum again.

Privacy and security

The bridge accepts connections only from your computer, requires a bearer token, and retains that token only in the current browser tab. It logs limited security events without recording the token, request headers, receiver list, or serial number. No RF, IQ, audio, decoded content, or receiver controls leave your computer through the bridge. APRS packets are rendered only in the current browser tab and are not saved or uploaded.