Configuration and running

Start the application using the command line and check for any errors. Logging to a file is by default disabled.

Please see the Setup tab first and make sure to click Save before starting TX or RX modes, otherwise you may get a segmentation fault.

Setup options include RX and TX frequency correction (in PPM), device access strings, RX and TX antenna settings as a string and your callsign (maximum 7 ASCII characters) which will be sent at the start and end of the transmission.

By default the device will operate in the 433 MHz ISM band.

Adjust TX gain in dB and RX sensitivity from the TX tab. If you are driving an external amplifier check the waveform for distorsion.

The select input in the lower right corner toggles between different operating modes.

Enable the TX and/or RX buttons depending on whether you want only RX, only TX or both.

Adjust the frequency from the TX tab either by using the dial widget or by entering it in the text box.

The transmitting power, receive sensitivity, main RX frequency and squelch values will be saved to the configuration file when you close the application and restored at startup.

The Tune page allows fine tuning 5-5000 KHz around the frequency with the slider, and monitoring the signal with the constellation display and the RSSI display.

The Spectrum page allows visualisation of the received signal. The maximum RX bandwidth depends on the operating mode selection. To zoom in, click and draw a rectangle on the graphic. To zoom out one step, right click. To tune the radio to a frequency, double click on the graphic. To zoom in or out, use the mouse scroll wheel. There are also options for FFT number of points, averaging and min/max display.

VOIP QRadioLink uses murmurd as a reflector with the Opus voice codec. VOIP is currently undergoing development.

Video page will display received video stream. Right now only a limited number of cameras are supported for TX, and ISO settings/ exposure of the camera might cause too low a framerate, which can't be transmitted properly.


Please report any issues you have encountered using the Github bug tracker


The project has a dedicated mailing list at Sourceforge which can be used to discuss issues, request features and contact developers. Send email to