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https://github.com/portapack-mayhem/mayhem-firmware.git
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Arne Luehrs
569bcaad22
* EPIRB RX: widen AFC capture range to +/-5 kHz The AFC estimate was only applied after carrier lock, so carrier acquisition ran on raw phase deltas and could only tolerate offsets of a few hundred Hz before the 0.6/0.7/1.6 rad detection thresholds (on the 12-sample accumulator) broke down. Track the carrier offset continuously in the IDLE state with a first-order loop (AFC_TRACK_ALPHA), so the de-biased accumulator self-centers for any offset within the discriminator Nyquist (~24 kHz) *before* the thresholds run. ALPHA = 0.005 pulls a +/-5 kHz offset under the 0.6 rad lock threshold in ~11 ms, well inside the 160 ms preamble / 80 ms stability window. The IDLE rise-detect threshold is also made symmetric (fabsf) now that the bias is removed. Also add the missing <cstdint> include to test_convert.cpp so the application_test suite compiles under the current toolchain. Verified: baseband_epirb_rx.elf builds (flash 53%, RAM 12%) and baseband_test passes.