SDR help

[Phishfry]

What does it give me?

It is an audio backend that some programs use. CubicSDR for example. It would be considered a dependency when you install the port.
Some programs use OSS backend instead like SDR++.

 

[Phishfry]

Can I enable it and disable it as and when I want to try it?

You are thinking about it wrongly.
Pulse Audio runs as a audio daemon/server running in the background. When a client program opens it looks for Pulse and the daemon answers with its capabilities.
You could have only one X11 program that depends on Pulse Audio or you might have several that use it.

Take a look at pavucontrol. It shows in a GUI what its doing. Listening for a programs audio request.

 

[Phishfry]

So a BSD user might not want Pulse Audio and its GPL license on their computer.

You can set make OPTIONS to set the audio backend in some ports. Changing backend audio system to OSS.
Not all ports with audio offer the option. Some ports might even use ALSA. The old Linux sound server before Pulse.

FreeBSD ports are compiled with the upstream defaults respected.
So Pulse Audio might be the default for a FreeBSD Port but you can look at port options to see if you have a choice.
comms/sdr++
Take a look at "Configuration Options" on this port for example. PORTAUDIO Sink or RTAUDIO SINK

 

[Phishfry]

If you look at the Configuration Options for comms/gqrx there are none.

There are clues why in the Makefile:

# XXX Use Portaudio as Gqrx is invariably linked to it
# (auto-detected and used through Gnuradio CMake files)
CMAKE_ARGS+= -DLINUX_AUDIO_BACKEND:STRING="Portaudio" \

 

[astyle]

Me and user astyle had a head bump years ago. He sorta accused me of lying about a browser reaching back into ports tree and running Build Components.
I got all huffy and said are you calling me a liar. Pretty crappy words but it was not false.

What I neglected to mention was I was running X11/SeaMonkey as root user and indeed Internet Components can access stuff you never imagined from the ports build directory when running as root.

Totally my fault and I am sorry I did not tell astyle all the facts. But I like to think I have reformed. Learned a valuable lesson.

May have been a bad choice of words on my part... in the FreeBSD Ports Collection, a browser would have build dependencies (all of 'em also in the Ports Collection). I would not call them security holes necessarily.

I do agree that running a browser as root is a bad idea, because that opens up the entire disk/filesystem to whatever cookies the browser slurps up from the Internet.

FWIW, I compile all the available sound systems in, be it PulseAudio, sndio, pipewire, you name it. If it's available in the Ports Collection, I'll compile it and use it.

 

[Anna2Kowalska]

Try running gqrx as a normal user instead of root that's usually the cleaner way. Make sure your user is in the operator group and set up a devd rule for the RTL-SDR so it gets proper permissions on plug-in. Also check that dbus is enabled (dbus_enable="YES" in /etc/rc.conf) and restart it. Once that's sorted, gqrx should detect the device fine. I had similar issues until I stopped running everything as root.

I'm just getting started with SDR although I bought my RTL-SDR V4 dongle some time ago without knowing how to try it out.

After a recent post I managed to install various pkgs with varying degrees of success with their usage.

The only thing which has proved successful is rtl_fm from comms/rtl-sdr with which I have stumbled upon a frequency where I can actually listen to a radio station.

Can anyone suggest what else I should try? sdrpp says that it failed to detect any supported platform which is strange since rtl_fm uses the same device and works.

I have recently bought a dipole antenna but it doesn't seem to help reception. Maybe it isn't set up correctly.

 

[Espionage724]

Can I enable it and disable it as and when I want to try it?

With Xfce, PulseAudio default autostarts in Startup/Session settings. The only things I use that need PA's daemon are Firefox and OBS Studio, so I disable that PA autostart, use sndio instead for Firefox (sndiod autostart + cubeb), and for OBS I start up PA manually in a minimized Terminal so I can either close it when done with OBS or it auto-close with --exit-idle-time= (180's 3 mins; not sure if OBS holds PA open so idle might need disabled or increased):

xfce4-terminal --minimize -T 'OBS [PA]' --window -x '/usr/local/bin/pulseaudio' --log-level='0' --exit-idle-time='180'

Afaik there's no real advantage and PA seemingly works fine default/Firefox/OBS, but I ran into enough oddities with PA on Linux that I'd prefer to avoid it when possible

 

[Phishfry]

unitrunkers devd rules from reddit for the RTL-SDR stick.

notify 100 {
match "system" "USB";
match "subsystem" "DEVICE";
match "type" "ATTACH";
match "vendor" "0x0bda";
match "product" "0x283[28]";
action "chmod 660 /dev/$cdev";
};

With these three I have my permissions back where they should be to 660 in my devd rule.
pw groupmod pulse -m $user_name
pw groupmod pulse-access -m $user_name
pw groupmod pulse-rt -m $user_name

 

[balanga]

I can listen to an FM station using rtl_fm which uses SoX to output a noise, but get no audio output from sdrpp.

What should I look at?

Can sdrpp use Sox?