Extrinsic 1605-1

{
  "heartbeat": {
    "blockNumber": 1601,
    "sessionIndex": 26,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x762f1717d6d2d610e1037abc3337fb404623ff8ddd2d86440288e5ddf7b0575067173f02196bfe4a1afab18652337478ca2bb0e54aa96a99842b5c229c7acb88"
}