NODE 734 — TERMINAL RELAY

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    0.8914,
    0.8049,
    1.7716,
    0.541,
    -1.2658,
    -0.467,
    0.5473,
    -0.5583,
    -0.8284,
    0.7056,
    0.4476,
    -1.4527,
    -1.2864,
    -0.0958,
    -0.8251,
    -1.1703,
    1.0005,
    2.316,
    1.2412,
    1.1138,
    1.9874,
    0.5119,
    -1.8555,
    -1.6478,
    -0.8646,
    -1.8591,
    -1.7461,
    0.5692,
    1.3116,
    0.117,
    0.5037,
    1.5569,
    0.2827,
    -0.9993,
    0.2898,
    1.1435
  ],
  "instructions": "This is a sampled audio waveform created by summing pure sine waves. Each sine wave has a rationally-related frequency (consonant musical interval). To decode:\n1. Compute FFT of the waveform to find frequency peaks\n2. Apply a Hann window before FFT to reduce spectral leakage\n3. Sort peaks by frequency (low to high)\n4. For each adjacent pair, compute: semitones = 12 * log2(f2/f1)\n5. Round semitones to the nearest integer\n6. Map each semitone count to a letter using the table\nConcatenate letters in order.\n\nNo noise \u2014 peaks should be clean.",
  "semitone_to_letter": {
    "0": "A",
    "2": "B",
    "3": "C",
    "4": "D",
    "5": "E",
    "7": "F",
    "8": "G",
    "9": "H",
    "10": "I",
    "11": "J",
    "12": "K",
    "14": "L",
    "15": "M",
    "16": "N",
    "17": "O",
    "19": "P",
    "21": "Q",
    "22": "R",
    "24": "S",
    "26": "T",
    "28": "U",
    "29": "V",
    "31": "W",
    "33": "X",
    "35": "Y",
    "36": "Z"
  },
  "hann_window_formula": "w[i] = 0.5 * (1 - cos(2*pi*i/(n-1)))",
  "fft_tip": "Sample rate = 4000 Hz (Nyquist = 2000 Hz). All signal frequencies are between 80 Hz and 1900 Hz.",
  "hint": "3 frequencies \u2192 2 semitone intervals \u2192 2 letters. Apply Hann window, FFT, find peaks, compute log2 ratios.",
  "answer_format": "single lowercase letter"
}