Lab043: add hardware diagnostics and HackRF comparison tools

tests/test_lab043_calibration.py

@@ -764,6 +764,39 @@ def test_symbol_sample_phase_is_selected_separately(initial_sample_phase: int) -
     assert found["score"] > 0.99
 
 
+def test_spectral_tone_start_fallback_finds_narrow_tones_without_broadband_jump() -> None:
+    sample_rate = 240_000.0
+    rng = np.random.default_rng(43)
+    samples = (
+        rng.normal(0.0, 0.08, 240_000)
+        + 1j * rng.normal(0.0, 0.08, 240_000)
+    )
+    tone_start = 96_000
+    tone_count = 60_000
+    indexes = np.arange(tone_count, dtype=np.float64)
+    samples[tone_start : tone_start + tone_count] += 0.025 * (
+        np.exp(-1j * 2.0 * np.pi * 50_000.0 * indexes / sample_rate)
+        + np.exp(1j * 2.0 * np.pi * 50_000.0 * indexes / sample_rate)
+    )
+
+    with pytest.raises(RuntimeError, match="10"):
+        lab043.locate_calibration_tone_start(
+            samples,
+            sample_rate,
+            block_samples=2048,
+            hop_samples=1024,
+        )
+    found = lab043.locate_calibration_tone_start_spectral(
+        samples,
+        sample_rate,
+        block_samples=8192,
+        hop_samples=2048,
+        required_consecutive_blocks=3,
+    )
+
+    assert tone_start - 8192 <= found <= tone_start + 2048
+
+
 def test_one_control_packet_passes_crc() -> None:
     assert lab043.control_packet_crc_roundtrip(b"known payload")