Archive | Linux RSS feed for this section


21 Dec

Pulse Audio
Prior to installation of gqrx make sure pulseaudio is available during build by installing the following:

Install gqrx
git clone
cd gqrx
mkdir build
cd build
qmake ..
make -j8
sudo make install

Typical device strings
For the b200:

For the X310 with LFRX in slot 2:

For the X310 with WBX in slot 1:

For the N210 with LFRX:

When switching between devices in gqrx the gain control changes will segfault the application.  Fix this by deleting the “gains” section in:

Sending gqrx audio to fldigi
Install fldigi with yum

Configure fldigi sound card to use pulseaudio, leaving server string empty

Launch pulseaudio volume control, and under recording tab, fldigi capture from monitor of built-in audio analog stereo, and set level to 0 dB.

Adjust fldigi waterfall upper signal level and signal range.

Setting up NI GPIB-USB-HS under Linux

26 Jul

Mostly stolen from:

Note unlike the ni_usb_b, this is the ni_usb_hs so no firmware has to be loaded at boot, thus gpib_config can be called directly.

Get latest source code

Typical build in /usr/local/src with
sudo make install

Edit configuration
sudo vi /etc/gpib.conf

board_type = "ni_usb_b"
name = "gpib0"

Add udev rules
sudo vi /etc/udev/rules.d/99-linux_gpib_ni_usb.rules

SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="3923", ATTR{idProduct}=="709b", MODE="660", GROUP="username", SYMLINK+="usb_gpib"
SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="3923", ATTR{idProduct}=="709b", RUN+="/usr/local/sbin/gpib_config"
KERNEL=="gpib[0-9]*", ACTION=="add", MODE="660", GROUP="username"

sudo udevadm control –reload-rules

Note udev will not run the gpib_config at boot, so add it in rc.local
sudo vi /etc/rc.d/rc.local

exit 0

sudo chmod +x /etc/rc.d/rc.local
sudo systemctl enable rc-local.service
systemctl status rc-local.service

Now plug in the adapter and run ibtest
Reboot and run ibtest

Linux Multimedia

19 Jul

Logitech C615 HD Webcam
sudo vi /etc/udev/rules.d/99-webcam.rules

SUBSYSTEMS=="usb", ATTRS{idVendor}=="046d", ATTRS{idProduct}=="082c", MODE:="0666"

sudo udevadm control --reload-rules

Dell XPS 13 Webcam
sudo vi /etc/udev/rules.d/99-webcam.rules

SUBSYSTEMS=="usb", ATTRS{idVendor}=="0bda", ATTRS{idProduct}=="5752", MODE:="0666"

sudo udevadm control --reload-rules

RPM Fusion Repository
sudo yum localinstall --nogpgcheck$(rpm -E %fedora).noarch.rpm$(rpm -E %fedora).noarch.rpm

GUVCView Webcam Recording
sudo yum install libwebcam guvcview

Change resolution to 1280×720 on XPS-13

Set sound device to hw:2,0 for Logitech webcam

Screen Recording
sudo yum install gtk-recordmydesktop

Set sound device to DEFAULT for Logitech webcam

May also need to use hw:0,0 (use arecord -l to list input devices)

Video Editing
sudo yum install openshot

Video Playback
sudo yum install vlc

Fedora 20 x86_64 Linux Install Notes

7 Feb

Hardware Configuration
2 TB HDD on Intel 6G SATA port 0, /dev/sda, (Windows 7)
96 GB SSD on Intel 6G SATA port 1, /dev/sdb, (Intel RST cache for Windows 7)
2 TB HDD on Intel 3G SATA port 2, /dev/sdc, (Shared Windows / Linux)
DVD on Intel 3G SATA port 4
240 GB SSD on Marvel 6G SATA port 0, /dev/sdd, (Linux)
Asus P8Z68 Deluxe/Gen3 Bios
RAID for Intel SATA controller
Marvel controller enabled
Boot order (DVD port 4, USB, HDD port 0)
Intel RST Option ROM
RAID0(Cache) for SSD port 1
EasyBCD installed on Windows boot partition.
Boot selection for Linux (/dev/sdd1) or Windows (/dev/sda1)

Fedora Boot CD
Tab at install to modify boot commands.
Remove quiet.

Network Config
IPV4: manual
IPV6: ignore

Location: Chicago

Software Selection
XFCE Desktop (development tools, extra plugins)

Choose 2 TB HDD (the last one in the list)
Automatic partitioning

After Reboot
Create user and add to admin group
Synchronize time over network

Change to (e.g. runlevel 3)
sudo rm /etc/systemd/system/
sudo ln -s /lib/systemd/system/ /etc/systemd/system/

Change GRUB
sudo vi /etc/default/grub and remove rhgb quiet
sudo grub2-mkconfig -o /boot/grub2/grub.cfg

If for some reason Intel RST was enabled during install, the above will re-scan for bootloaders


Update the System
sudo dnf update

Enable root Account
sudo passwd

Install Custom Shell Scripts
cp .bash_profile ~
cp .bashrc ~
cp .profile ~
cp .vimrc ~
sudo cp .bashrc /root

Directory Permissions
sudo chmod 777 /usr/local/src

Add Library Path to Linker
sudo vi /etc/
add /usr/local/lib
add /usr/local/lib64
sudo ldconfig

sudo /usr/bin/firewall-config
Change default zone to internal
Trust services as required

sudo system-config-printer
Search for network printer at
Use DirectJet port
Choose driver for Brother HL-5170DN
Use BR-Script3

sudo usermod -a -G audio username
(must reboot to take effect)

The nm-applet gives insufficent permission errors when changing WiFi due to startxfce4 instead of using a display manager. This will fix it:

sudo vi /etc/polkit-1/rules.d/50-org.freedesktop.NetworkManager.rules
polkit.addRule(function(action, subject) {
if ("org.freedesktop.NetworkManager.") == 0 && subject.isInGroup("myusername")) {
return polkit.Result.YES;

(must reboot to take effect)