Gqrx direct sampling on RTL-SDR not working?

maciek.t...@gmail.com

unread,

Aug 30, 2018, 4:01:55 AM8/30/18

to Gqrx SDR

Hello!

I'm trying to run my RTL-SDR generic dongle in direct sampling mode. In device string i input "rtl=0 ; direct_samp=2". It making only gqrx crash when I click play. When i run gqrx again,

device is set to "Other". If i input in device string line only "direct_samp=2", then receiver working in direct sampling mode (i hear it) but i can't operating tuning etc...

Is this gqrx bug? I know gr-osmo and rtl-sdr are accepting "direct_samp" option, and in grc it works fine.

Alexander Fasching

unread,

Aug 30, 2018, 4:20:34 AM8/30/18

to gq...@googlegroups.com

Please post the output from the terminal and provide more information
about your system:

* Version of Gqrx
* Distribution
* How did you install Gqrx? (Repository, PPA, from source...)
* PC or Raspberry Pi?
* Version of gr-osmosdr

If gr-osmosdr supports it, then Gqrx should support it too, because it
uses gr-osmosdr as backend. The device string you enter in Gqrx is
passed directly to the gr-osmosdr source.

The device switching to "Other" can be ignored.

> --
> You received this message because you are subscribed to the Google
> Groups "Gqrx SDR" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to gqrx+uns...@googlegroups.com
> <mailto:gqrx+uns...@googlegroups.com>.
> To post to this group, send email to gq...@googlegroups.com
> <mailto:gq...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/gqrx/e9f8db18-fe5f-4919-ab8c-29352143d11b%40googlegroups.com
> <https://groups.google.com/d/msgid/gqrx/e9f8db18-fe5f-4919-ab8c-29352143d11b%40googlegroups.com?utm_medium=email&utm_source=footer>.
> For more options, visit https://groups.google.com/d/optout.

maciek.t...@gmail.com

unread,

Aug 30, 2018, 4:56:47 AM8/30/18

to Gqrx SDR

Gqrx version 2.9 from ubuntu 18.10 repository (exactly Kubuntu), architecture x86-64 Intel, gr-osmosdr version 0.1.4. Console output:

aciek@ashaneen:~$ gqrx
linux; GNU C++ version 7.3.0; Boost_106501; UHD_003.010.003.000-0-unknown

Controlport disabled
No user supplied config file. Using "default.conf"
gr-osmosdr 0.1.4 (0.1.4) gnuradio 3.7.11
built-in source types: file osmosdr fcd rtl rtl_tcp uhd miri hackrf bladerf rfspace airs
py airspyhf soapy redpitaya freesrp
FM demod gain: 3.05577
Resampling audio 96000 -> 48000
IQ DCR alpha: 1.04166e-05
Using audio backend: auto
BookmarksFile is /home/maciek/.config/gqrx/bookmarks.csv
Cannot connect to server socket err = Nie ma takiego pliku ani katalogu
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock

RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (hw:0,0), Urządzenie lub zasoby
zajęte.

RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (hw:0,2), Urządzenie lub zasoby
zajęte.

Detached kernel driver
Found Rafael Micro R820T tuner
Reattached kernel driver
getDeviceList : Available input devices:
   0 : "KSMOD RTL2838UHIDIR"
   1 : "RFSPACE SDR-IQ Receiver"
   2 : "RFSPACE SDR-IP Receiver"
   3 : "RFSPACE NetSDR Receiver"
   4 : "RFSPACE Cloud-IQ Receiver"
   5 : "hw:HDA Intel,0"
   6 : "hw:HDA Intel,2"
   7 : "hw:USB Device 0x46d:0x807,0"
   8 : "default"
   9 : "Generic RTL2832U OEM :: "
   10 : "RTL-SDR Spectrum Server"
   11 : "Red Pitaya Transceiver Server"
   12 : "Complex Sampled (IQ) File"
Loading configuration from: "default.conf"
Configuration file: "/home/maciek/.config/gqrx/default.conf"
gr-osmosdr 0.1.4 (0.1.4) gnuradio 3.7.11
built-in source types: file osmosdr fcd rtl rtl_tcp uhd miri hackrf bladerf rfspace airs
py airspyhf soapy redpitaya freesrp
Using device #0 KSMOD RTL2838UHIDIR
Detached kernel driver
Found Rafael Micro R820T tuner
[R82XX] PLL not locked!
[R82XX] PLL not locked!
IQ DCR samp_rate: 1.024e+06
IQ DCR alpha: 9.76562e-07
Changing NB_RX quad rate: 96000 -> 1.024e+06
New antenna selected: "RX"
********************
Gain name: "LNA"
     min: 0
     max: 49.6
    step: 0.5
********************
No change in output device:
old:
new:
[R82XX] PLL not locked!
IQ DCR samp_rate: 1.8e+06
IQ DCR alpha: 5.55555e-07
Changing NB_RX quad rate: 1.024e+06 -> 1.8e+06
Requested sample rate: 1800000
Actual sample rate   : "1800000.000000"
New FFT rate: 25 Hz
Requested bandwidth: 0 Hz
Actual bandwidth   : 0 Hz
setFreqCorr : 7 ppm
setFreqCorr : 7 ppm
New LNB LO: 0 Hz
[R82XX] No valid PLL values for 3569337327 Hz!
r82xx_set_freq: failed=-1
New mode index: 3
Filter preset for mode 3 LO: -5000 HI: 5000
Generating taps for new filter   LO:-5000   HI:5000 TW:2000   Taps: 115
setFftRate to "25 fps"
New FFT rate: 25 Hz
New FFT rate: 25 Hz
setFftSize to "16384"
Changing baseband FFT size to 16384
New FFT rate: 25 Hz
New FFT rate: 25 Hz
Generating taps for new filter   LO:-5000   HI:5000 TW:2000   Taps: 115
Configure I/O devices.
CIoConfig : Available output devices:
   0 : "Wbudowany dźwięk Analogowe stereo"
saveConfig
New LNB LO: 0 Hz
saveSettings *** FIXME_ SQL on/off
New FFT rate: 25 Hz
Loading configuration from: "/home/maciek/.config/gqrx/default.conf"
Configuration file: "/home/maciek/.config/gqrx/default.conf"
Reattached kernel driver
gr-osmosdr 0.1.4 (0.1.4) gnuradio 3.7.11
built-in source types: file osmosdr fcd rtl rtl_tcp uhd miri hackrf bladerf rfspace airs
py airspyhf soapy redpitaya freesrp
Using device #0 KSMOD RTL2838UHIDIR
Detached kernel driver
Found Rafael Micro R820T tuner
[R82XX] PLL not locked!
[R82XX] PLL not locked!
IQ DCR samp_rate: 1.024e+06
IQ DCR alpha: 9.76562e-07
Changing NB_RX quad rate: 1.8e+06 -> 1.024e+06
New antenna selected: ""
New antenna selected: "RX"
********************
Gain name: "LNA"
     min: 0
     max: 49.6
    step: 0.5
********************
No change in output device:
old:
new:
[R82XX] PLL not locked!
IQ DCR samp_rate: 1.8e+06
IQ DCR alpha: 5.55555e-07
Changing NB_RX quad rate: 1.024e+06 -> 1.8e+06
Requested sample rate: 1800000
Actual sample rate   : "1800000.000000"
New FFT rate: 25 Hz
Requested bandwidth: 0 Hz
Actual bandwidth   : 0 Hz
setFreqCorr : 7 ppm
New LNB LO: 0 Hz
New mode index: 3
Filter preset for mode 3 LO: -5000 HI: 5000
Generating taps for new filter   LO:-5000   HI:5000 TW:2000   Taps: 115
setFftRate to "25 fps"
New FFT rate: 25 Hz
New FFT rate: 25 Hz
setFftSize to "16384"
New FFT rate: 25 Hz
Generating taps for new filter   LO:-5000   HI:5000 TW:2000   Taps: 115
terminate called after throwing an instance of 'std::runtime_error'
what(): In hierarchical block source_impl, output 1 is not connected internally
Przerwane (zrzut pamięci)

Last line mean "Stop (dump memory)" in polish language.

Alexander Fasching

unread,

Aug 30, 2018, 5:14:43 AM8/30/18

to gq...@googlegroups.com

Your device string is not correct.
Options are separated by ",", not ";" and I don't think you can have spaces.
Use "rtl=0,direct_samp=2".

> --
> You received this message because you are subscribed to the Google
> Groups "Gqrx SDR" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to gqrx+uns...@googlegroups.com
> <mailto:gqrx+uns...@googlegroups.com>.
> To post to this group, send email to gq...@googlegroups.com
> <mailto:gq...@googlegroups.com>.
> To view this discussion on the web visit

> https://groups.google.com/d/msgid/gqrx/f5001ae3-1b14-4dda-90d9-bd441220dcb2%40googlegroups.com
> <https://groups.google.com/d/msgid/gqrx/f5001ae3-1b14-4dda-90d9-bd441220dcb2%40googlegroups.com?utm_medium=email&utm_source=footer>.

maciek.t...@gmail.com

unread,

Aug 30, 2018, 5:20:02 AM8/30/18

to Gqrx SDR

Thank You very much Alexander!

I was fighting with it 3 years and nobody on polish forums was can't help me. Now it's really working! :) :) :)

W dniu czwartek, 30 sierpnia 2018 10:01:55 UTC+2 użytkownik maciek.t...@gmail.com napisał:

Reply all

Reply to author

Forward