#1160·urh

Incorrect magnitude calculation on Raspberry Pi 5 (arm64), possible data conversion bug, incorrect demodulation

Author: germano2239Created Apr 8, 2025Updated Mar 19, 2026
Actual Behavior

URH compiled from source on raspberry 5 has some kind of conversion issues with signal magnitudes. the problem is verified by acquiring a signal with a RTL-SDR device and saving it to .complex16s format on the raspberry 5. Opening the file on x64 linux PC shows the data has been correctly acquired and saved by the raspberry. opening the same file on the raspberry itself shows weird demodulation chart. The problem is visible also during live sniffing but saving to file and loading helped me to isolate the problem which initially seemed to be an acquisition one.

Correct demodulation and IQArray.magnitude data:

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Incorrect demodulation and IQArray.magnitude data:

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I've been battling with this issue for a couple of days now, any help would be immensely appreciated.