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        "min_abs": 0.020953,
        "max_abs": 4.126624,
        "positive": 139,
        "negative": 35,
        "zero": 0
      },
      "success": false,
      "iterations_used": 24,
      "final_syndrome_weight": 34,
      "message91": null,
      "message91_sha256_16": "07985c5b49461190",
      "codeword174_sha256_16": "c148a530d15360d5",
      "trace": [
        {
          "iteration": 0,
          "syndrome_weight": 42
        },
        {
          "iteration": 1,
          "syndrome_weight": 39
        },
        {
          "iteration": 2,
          "syndrome_weight": 35
        },
        {
          "iteration": 3,
          "syndrome_weight": 43
        },
        {
          "iteration": 4,
          "syndrome_weight": 38
        },
        {
          "iteration": 5,
          "syndrome_weight": 37
        },
        {
          "iteration": 6,
          "syndrome_weight": 41
        },
        {
          "iteration": 7,
          "syndrome_weight": 43
        },
        {
          "iteration": 8,
          "syndrome_weight": 46
        },
        {
          "iteration": 9,
          "syndrome_weight": 38
        },
        {
          "iteration": 10,
          "syndrome_weight": 34
        },
        {
          "iteration": 15,
          "syndrome_weight": 36
        },
        {
          "iteration": 20,
          "syndrome_weight": 40
        }
      ]
    }
  ],
  "decodes": [],
  "outputs": {
    "ldpc_soft_decode_json": "/decoders/js8_decoder/runtime/ldpc_soft_decode/step38_ldpc_soft_decode.json"
  },
  "warnings": [
    "Step 38 runs bounded normalized-min-sum soft LDPC over the best-ranked FT8-style Gray/interleaver mapping candidates against the public (174,91) matrix contract.",
    "This still does not unpack JS8 text or validate CRC/message payloads.",
    "If success is true and syndrome_weight is 0, the next step can unpack the 91-bit message. Otherwise more timing, Costas/data-symbol boundary, deinterleaver/order or LLR tuning is required."
  ],
  "next_action": "Upload Step35 logs. If no valid codeword, inspect best mapping_meta/final_syndrome_weight and continue timing/interleaver/LLR tuning; if valid, add JS8 message unpack/CRC."
}