SDR Quest: Looking for Software Defined Radios for FreeBSD

Audio output is broken for this port.
To be honest I just posted an image to show that I was getting some output from my device.

I still haven't figured out how to get any audio output from sdr++ but have managed to listen to a station using a command line program

rtl_fm -f 100.9M -M wbfm -s 200k -r 48k | play -r 48k -t raw -e signed-integer -b 16 -c 1 -

so I should be able to get sdr++ working with some tinkering.
 
Under Module Manager, I don't see Audio Output. I only see Audio Source.
Its a weird setup. You want to choose from the dropdown in that settings area."Audio Source".
To the left of the dropdown is an empty box. You want to add a new device by Naming it in that box.
Its really an odd setup.. Look online for help. That's how I figured it out.

It still had really bad audio quality when I got it working compared to gqrx.
 
To be honest I just posted an image to show that I was getting some output from my device.

I still haven't figured out how to get any audio output from sdr++ but have managed to listen to a station using a command line program

rtl_fm -f 100.9M -M wbfm -s 200k -r 48k | play -r 48k -t raw -e signed-integer -b 16 -c 1 -

so I should be able to get sdr++ working with some tinkering.
Can I scan for stations using rtl_fm ?
 
Your output for dump1090 is empty. No catching that signal or some problem.
Did you notice this post:

You can also use rtl_adsb -V to see the messages.

rtl_adsb -V
Code:
Found 1 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Tuner gain set to automatic.
Tuned to 1090000000 Hz.
Exact sample rate is: 2000000.052982 Hz
Sampling at 2000000 S/s.
*abf8b1b957d2a0b75a9a0252090a;
DF=21 CA=3
ICAO Address=f8b1b9
PI=0x52090a
Type Code=10 S.Type/Ant.=7
--------------
*8934d333eace69d43779288dea92;
DF=17 CA=1
ICAO Address=34d333
PI=0x8dea92
Type Code=29 S.Type/Ant.=2
--------------
*cdaaf1a323202571c35ce0fe5159;
DF=25 CA=5
ICAO Address=aaf1a3
PI=0xfe5159
Type Code=4 S.Type/Ant.=3
--------------
*c7d414cd75242e3230ae04573f55;
DF=24 CA=7
ICAO Address=d414cd
PI=0x573f55
Type Code=14 S.Type/Ant.=5
--------------
*a9203caefbb10737bfdce2b29c99;
DF=21 CA=1
ICAO Address=203cae
PI=0xb29c99
Type Code=31 S.Type/Ant.=3
--------------
*a82234ae8ae9f930e02ca272c5da;
DF=21 CA=0
ICAO Address=2234ae
PI=0x72c5da
Type Code=17 S.Type/Ant.=2
--------------
*b41c5c332f1ea460a5406cc323d6;
DF=22 CA=4
ICAO Address=1c5c33
PI=0xc323d6
Type Code=5 S.Type/Ant.=7
--------------
*9adb21856b69b28afd8ce815359b;
DF=19 CA=2
ICAO Address=db2185
PI=0x15359b
Type Code=13 S.Type/Ant.=3
--------------
 
I have my homemade ADB-S Antenna working. I had it together last night but no signals????
Turns out I had used the wrong cable and it was female to female. No center pin.
I noticed it tonight and fixed it then got my first 1090 output with it.

Now seek other signals nearby and see where "Center" frequency is ??? Tune with the spectrum analyzer? I don't want to buy a meter.

misc/py-QSpectrumAnalyzer
 
The help for rtl_power shows this as a scan.


rtl_power -f 100M:1G:1M -i 5m -1 survey.csv
I already did this but don't know how to parse the output. The first two fields are date and time, but I can't figure out the rest.

Code:
2026-06-09, 13:33:32, 88000000, 90500000, 39062.50, 3712, -2.32, -2.28, -2.11, -1.96, -1.38, -0.77, 0.08, 0.36, 0.75, 2.31, 6.54, 3.88, 1.79, 1.61, 1.74, 1.88, 1.75, 2.02, 2.40, 2.04, 1.55, 1.76, 2.37, 1.88, 1.99, 1.99, 2.08, 2.43, 3.48, 2.52, 2.43, 2.66, 2.98, 2.9
2026-06-09, 13:33:32, 90500000, 93000000, 39062.50, 3712, 1.36, -1.34, -1.07, -0.23, 1.30, 0.67, 0.79, 0.79, 1.23, 1.67, 2.41, 2.52, 2.96, 3.04, 3.73, 3.93, 3.76, 3.18, 2.31, 1.85, 1.79, 1.75, 1.57, 1.58, 1.52, 1.88, 2.38, 4.23, 5.09, 5.88, 4.13, 2.39, 2.42, 2.42,
2026-06-09, 13:33:32, 93000000, 95500000, 39062.50, 3712, 0.78, -2.92, -3.30, -2.36, -1.02, -0.19, 0.56, 1.35, 1.21, 1.03, 2.30, 1.96, 1.82, 3.37, 3.17, 2.04, 2.39, 1.42, 1.24, 1.60, 1.12, 1.15, 1.06, 1.62, 0.94, 0.83, 0.86, 1.30, 1.64, 1.59, 1.30, 1.26, 1.44, 1.44
2026-06-09, 13:33:32, 95500000, 98000000, 39062.50, 3712, -4.55, -4.17, -3.83, -3.49, -2.85, -2.30, -1.75, -0.15, -0.61, -0.38, 0.38, -0.52, -0.41, 0.08, -0.34, -0.13, 0.60, 0.07, 0.25, 1.55, 1.36, 3.46, 9.31, 19.38, 11.17, 3.58, 1.62, 0.79, 0.21, 0.24, 0.61, 0.07,
2026-06-09, 13:33:32, 98000000, 100500000, 39062.50, 3712, -9.21, -8.68, -8.33, -7.68, -6.94, -4.65, -5.13, -3.79, -0.12, -1.09, -1.20, -3.00, -2.91, -1.56, -3.75, -3.64, -4.28, -4.36, -4.44, -4.79, -4.50, -3.61, -3.91, -3.69, -3.65, -3.74, -3.32, -3.94, -3.68, -2.
2026-06-09, 13:33:32, 100500000, 103000000, 39062.50, 3712, -5.93, -5.42, -4.89, -4.27, -3.12, -2.84, -1.92, -0.24, 1.96, 7.94, 18.86, 13.08, 4.24, 1.43, -0.39, -1.14, -1.06, -1.45, -0.58, 1.27, 0.33, -1.34, -0.62, -1.46, -2.33, -2.51, -2.28, -1.25, 2.63, 0.33, -2.
2026-06-09, 13:33:32, 103000000, 105500000, 39062.50, 3712, -9.07, -9.23, -8.26, -6.92, -4.71, -2.69, -4.85, -4.90, -4.27, -2.87, 1.20, -1.89, -4.07, -4.14, -4.28, -3.94, -4.27, -4.48, -4.79, -5.02, -4.58, -4.10, -3.68, -0.58, -3.23, -3.63, -2.57, -1.68, 0.53, 3.19
2026-06-09, 13:33:32, 105500000, 108000000, 39062.50, 3712, 2.69, 4.17, 1.84, 1.68, 2.33, 1.48, 1.54, 1.60, 1.65, 1.82, 1.75, 1.62, 1.83, 2.16, 2.33, 2.78, 2.10, 2.22, 2.25, 2.15, 2.09, 2.36, 2.76, 2.83, 2.62, 2.70, 3.41, 4.24, 4.81, 5.45, 5.30, 5.90, 21.41, 21.41,
 
I already did this but don't know how to parse the output. The first two fields are date and time, but I can't figure out the rest.

how to parse output from rtl_power
rtl_power outputs a CSV-like format where each line represents a frequency sweep segment and contains power measurements for many frequency bins.
A typical line looks like:
2026-06-10, 14:30:00, 88M, 108M, 12500, 1600, -45.2, -46.1, -47.0, ...
The fields are:
ColumnMeaning
1Date
2Time
3Start frequency (Hz)
4Stop frequency (Hz)
5Bin size (Hz)
6Number of samples/measurements
7+Power values (dB) for each frequency bin
 
I was pleasantly surprised that my antenna built for ADB also picks up FM Radio inside the house. I was not expecting that.
I did go long on the radials but maybe 800MHz was what I figure I have now.
Playing with gain in the SDR programs. I see a lighter colored waterfall when I go to 0 or -1 gain.
 
CubicSDR works with comms/soapysdr-rtlsdr also installed.
Do you have PulseAudio output over system speakers? I am having troubles with audio here. Looked at pavucontrol and everything seemed ok.

What about REMOTE radio setup. Maybe radio receiver on ARM64 board, front end on laptop.

gqrx-remote on Arm board? Anybody doing that? Perhaps rtl_tcp and gqrx?
 
see CubicSDR has a tab labeled MODEM in the upper left. Do this only work with certain devices?
So what I am guessing is this. You can use an external Ham Radio and control it via serial/usb with an SDR program like CubicSDR. That is considered a modem.

Is that correct?

Perhaps you need to install SoapyRTLSDR?
Found that one back in Post #35
Thanks for your assistance. I think it is a user rights problem.
 
unitrunkers devd rules from reddit for the RTL-SDR stick.

Drop this in as /usr/local/etc/devd/rtlsdr.conf
Code:
notify 100 {
match "system" "USB";
match "subsystem" "DEVICE";
match "type" "ATTACH";
match "vendor" "0x0bda";
match "product" "0x283[28]";
action "chmod 660 /dev/$cdev";
};

He mentions user "operator" but what about a group like "video" used for video users. Does a similar concept for "audio" users not exist?
 
Found that one back in Post #35
Thanks for your assistance. I think it is a user rights problem.
yes
Code:
pw groupmod wheel -m $user_name
pw groupmod operator -m $user_name
pw groupmod dialer -m $user_name
pw groupmod video -m $user_name
pw groupmod audio -m $user_name
pw groupmod webcamd -m $user_name
 
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