qrm-tools

Some SDR tools I wrote to help hunt QRM

Setup

pip install -r requirements.txt

Requires an RTL-SDR and librtlsdr

Usage

record_rtlsdr.py - Record AM audio

Record AM audio at a center frequency for a given duration; saves a datetime-stamped WAV (or a path you specify).

# 30 seconds at 132 MHz, auto-named output (e.g. record_20250130_1000000_143022.wav)
python record_rtlsdr.py 132000000 30

# 10 seconds at 144.390 MHz, custom output file
python record_rtlsdr.py 144390000 10 -o my_recording.wav

# Record for 5 seconds every half hour
while true; do ./record_radio.py 132000000 5; sleep 1800; done

find_peak_freq.py

Analyze one or more WAV files: report the strongest frequency components (frequency in Hz, magnitude, dB FS).

# Strongest single peak per file
python find_peak_freq.py recording.wav

# Top 5 peaks
python find_peak_freq.py recording.wav -n 5

# Stats for a specific frequency (e.g. 120 Hz)
python find_peak_freq.py recording.wav -f 120

# One line per file: frequency and strength only
python find_peak_freq.py *.wav -q

wav_explorer.py

GUI to browse spectral plots and listen to recordings