Posts by SV1BDS

  • MY QO100 SETUP

    Hi Gerhard OE3GBB ,

    The help is:

    ./qpskdv.py --help

    Usage: qpskdv.py: [options]


    Options:

    -h, --help show this help message and exit

    -d DECIMATION, --decimation=DECIMATION

    Set Decimation [default=380]

    -e EAR, --ear=EAR Set Earphones hardware address [default=]

    -i IPADDRESS, --ipaddress=IPADDRESS

    Set IP address [default=192.168.1.100]

    -m MIC, --mic=MIC Set Mic hardware address [default=]

    -r RXFREQ, --rxfreq=RXFREQ

    Set Rx center frequency (KHz) [default=739750]

    -b TX_BUFFER_SIZE, --tx-buffer-size=TX_BUFFER_SIZE

    Set Tx buffer size [default=15]

    -t TXFREQ, --txfreq=TXFREQ

    Set Tx center frequency (KHz) [default=430750]


    Just rename (mv qpskdv.py.txt qpskdv.py) it.

    There are two major bugs: audio is not all the time produced and there are instant stops of Tx.

  • MY QO100 SETUP

    Hi Gerhard OE3GBB ,

    Nice !!! try to move the cursor to the right side of the screen. If it is desapears you have a second screen. If the cursor transformed to a double arrow, drag it to the left to be presented. If all these fails send me a screenshot (there is a tool in utilities).

  • MY QO100 SETUP

    Hi Gerhard OE3GBB ,

    You have to follow the instructions at Link except for the gr-iio which must follow the rules that I mention at the previous post (the cmake command is different).

  • MY QO100 SETUP

    Quote from OE3GBB

    Just wait, I will try to install Ubuntu 18.04 on a different machine and see if there is Grnuradio 3.7 in the package.

    73

    Yes it exist. But you have to do (cmake is changed!!!):

    GNU Radio 3.7

    On Ubuntu 16.04 or newer GNU Radio can be installed from the package management. The installed version should be compatible with the gr-iio package build from source. Libiio and gr-iio may also be available from the package management, but to get the latest and most feature complete work, it’s recommend to build it from the latest github sources.

    Code
    git clone https://github.com/analogdevicesinc/gr-iio.git
cd gr-iio
cmake -DCMAKE_INSTALL_PREFIX=/usr .
make sudo make install
cd ..
sudo ldconfig

  • MY QO100 SETUP

    Quote from OE3GBB

    Hi George, that is great news. What do I need to test? I allready do have a Ubuntu computer and a Pluto via ethernet.

    73 de Gerhard OE3GBB

    OE3GBB Nice!!! which version Ubuntu and GNURADIO do you have (I have 18.04 & 3.7)? Pluto is GPSDO clocked or have TCXO ? Pluto can RX and Tx at QO100 NB? If yes Rx is probably at 739.5-740. For Tx what is your frequency range? For PTT which method you use (when GPIO used Rx is not possible the same time as far as I know)? Can you Rx and Tx at the same time(I can do)? What is the IP address of the Pluto? My design goal is to do IP over QO100 using 44 class A address space.

  • MY QO100 SETUP

    OE3GBB some successful tests are performed at 940 using GNURADIO for digital voice. QPSK with HDLC and CODEC2 at 2400. Differential encoding and bit scrabling are used. A Pluto is used via Ethernet is used for both Tx and Rx. MER is also calculated. If you are interested using an RTL the .py can be created for testing. Now is far from optimum but it works. All flowgraph is using existing 3.7 boxes. FEC is planned to be included.

  • New TX set up

    Hi,

    One tip I use is to listen to 10.6 GHz LNB Lo of nearby LNBs at 850 MHz with the wider bandwidth you can use. This verify that your receiving system works.

  • MY QO100 SETUP

    Hi,


    A HF signal monitoring system is build for research usage. This project idea can be used, if desired, to daily monitor QO100 NB & WB activity and usage. Statistics also can be calculated.


    An active antenna (LA8AK circuit) with a 1m whip can receive 10 KHz-30 MHz. A 4 way splitter provide the signal among others to a USRP1 SDR with a 0-30MHz Rx card. The USRP1 is connected to a i5 1.6 GHz low consumption PC with a 4TB HD and a 60 GB SSD for Ubuntu 18.04. The PC runs at about 50% CPU. A GNURadio generated Python script runs every 2 min for 100 seconds. It has 16 bit 6.4 MHz sampling rate, so the same RF bandwidth received. Three frequencies ranges are covered (1.6-20.8 MHz total covered frequency range). The frequency selection criteria was that this range is relative non infected from local interference. If it is installed in a better environment all the 30 MHz range can be easy covered. So every cycle it takes 6 minutes and then is repeated.


    Two 1024 FFT points run, one 100 per second and the other one once a minute. This gives 6.25 KHz resolution bandwidth per FFT point. The minimum signals is -150 dBm and the maximum is -150+128=-22 dBm (dynamic range 128 dB). A resolution of 0.5 dB is archived. Data are saved in two category files. The low resolution is saved in 3 daily produced files, one per frequency range. The high resolution is saved once per 100 seconds (3 files per 6 minutes). The high resolution produced files are 7.2 GB per day, giving hundred of days storage capability. The creation of files is automated with cronjob entries. Only delete is not automated as manual activity is desired.


    To visualise the recorded data three possible images files can be produced. All of them are spectrograms with X axis the frequency, Y axis the time and colour the received signal strength in dBm. A colour bar with dBm values exists also. The produced .PNG files are : 100 sec high resolution data files, the 6.4 MHz wide daily data files and the 3 frequency ranges combined daily file. The combined and the 3 daily image files are auto produced daily. Sample outputs are attached. Time is local UTC+2. It can easy noticed in the combined file, the usage at broadcasts bands.


    Ideas for new features and improvements are welcome, some of existing ones are:

    - video animation of daily image (combined) files

    - IQ data storage on trigger event

    It is examined that daily combined image files will be available via my site.