airspy_rx nmux: end input stream exitting.

[zanco]

Hi, I try to change my openwebrx setup to one rtl-sdr and one arispy mini. I have completely removed the openwebrx and csdr and did start from scratch with the latest openwebrx and csdr. I allready had SoapySDR and the airspy part installed.

The rtl-sdr is running, on port 4952 and works.

the Airspy is supposed to run on port 4951 but I get this message:

[openwebrx-main] Configuration script not specified. I will use: "config_webrx.py" [openwebrx-import] Found plugin: plugins.dsp.csdr.plugin [openwebrx-main] nmux_bufsize = 15003648, nmux_bufcnt = 4 [openwebrx-main] Started rtl_thread: airspy_rx -f403.2 -r /dev/stdout -a2 -g16 -b0| nmux --bufsize 15003648 --bufcnt 4 --port 4951 --address 127.0.0.1 [openwebrx-main] Waiting for I/Q server to start... nmux: listening on 127.0.0.1:4951 nmux: (main thread/for) end input stream, exiting.

If I start airspy_rx -f 403.2 -w it writes an IQ file on the given frequency so that seems to work.

What else could I try ?

Thanks, Ben

[ha7ilm]

Ben,

Could you check if the following works?

airspy_rx -f403.2 -r /dev/stdout -a2 -g16 -b0 | csdr through > /dev/null

nmux should not quit unless the receiver command exits.

Andras

[zanco]

Hi Andras,

that command exits with no output at all.

but this does work: pe2bz@pe2bz-rooftop:~/openwebrx$ airspy_rx -f 403.2 -w Receive wav file: AirSpy_20170418_223836Z_403200kHz_IQ.wav Device Serial Number: 0x04A464C8355B4A0B Stop with Ctrl-C Streaming at 6.001 MSPS Streaming at 6.000 MSPS Streaming at 6.001 MSPS Streaming at 6.000 MSPS Streaming at 6.001 MSPS

Thanks, Ben

[ha7ilm]

that command exits with no output at all.

In that case, it is not nmux, simply the receiver command does not work. You could either use rx_tools, I think it is a fast workaround:

https://github.com/simonyiszk/openwebrx/wiki/Using-SoapySDR-via-rx_tools-with-OpenWebRX

...or try to figure out the command line for airspy_rx that writes the I/Q samples to the standard output.

[zanco]

Quick update: Hi, rx_tools gave the same result. However, after adding -d 0 to the line where I start the airspy that does work. Later more, I am @work now.

[zanco]

Well, I must say that I am impressed....

airspy_rx -d 0 -f403.2 -r /dev/stdout -a2 -g16 -b0 | csdr through > /dev/null also does work. So both airspy_rx and rx_tools require the pointing to the device, even though there is only one device detected. (while there are 2 other RTL dongles connected).

Keep in mind that other software for Airspy counts the gain in values between 1 and 21 but for these plugins the gain is in dB ! So 21 for the airspy is not the highest gain. I am using 40 (dB) now and it works nicely.

On an i3 with Ubuntu 16.04 and quite high FFT resolution the Airspy Mini runs on 6 MHz bandwidth with only 28 percent processor load. I am happy with that !

Regards, Ben

[ha7ilm]

Thanks for the info, I have added the -d0 to the article in the Wiki.