Gqrx on Hackberry Pi Zero 2W (NESDR Nano 3)

Step-by-step guide to get Gqrx SDR running smoothly on a Raspberry Pi Zero 2W Hackberry with a Nooelec NESDR Nano 3.

pre-rerequisites

Raspberry Pi Zero 2W (Hackberry)
NESDR Nano 3 RTL-SDR dongle
Kali Linux (or Debian-based)
Swapfile enabled (2GB+ recommended)

1. Install Required Packages

sudo apt update
sudo apt install gqrx-sdr rtl-sdr

2. Verify RTL-SDR Detection

lsusb | grep -i realtek
rtl_test -t

3. Disable DVB Module

sudo rmmod dvb_usb_rtl28xxu
echo 'blacklist dvb_usb_rtl28xxu' | sudo tee /etc/modprobe.d/no-rtl.conf

4. Start PulseAudio

pulseaudio --start

If that fails:

pulseaudio --system --disallow-exit --disable-shm

5. Create Minimal Gqrx Config

mkdir -p ~/.config/gqrx
nano ~/.config/gqrx/default.conf

Paste:

[General]
rec_dir=/tmp

[Input]
device_args=rtl=0
sample_rate=1024000
freq_corr=0

[Audio]
audio_output_device=None
audio_gain=1
volume=-10

[FFT]
fft_size=512
fft_rate=5
averaging=1
waterfall=0

6. Launch Gqrx

gqrx

7. Optimize Settings

File → I/O Devices: rtl=0, 1024000 sample rate, gain 30 dB
File → Audio Settings: Output = None
Tools → FFT Settings: Size = 256, Rate = 5 fps, Waterfall = Off

8. Tune to FM

Frequency: 100.1 MHz

If you see "PLL not locked!", make sure gain is set, sample rate is low, and you're in-range.

Optional: Enable Swap

swapon --show
sudo dphys-swapfile setup
sudo dphys-swapfile swapon
sudo systemctl enable dphys-swapfile

you're Done!

You now have a working SDR scanner running Gqrx on a Pi Zero 2W Hackberry.