# SDR ASAA1058025

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 3, 2010
- Submitted: July 6, 2010
- Operation: Air carrier
- Aircraft: [N559AS](https://openairdocs.org/aircraft/N559AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35178
- Aircraft time: 14,340 hours, 4,286 cycles
- System (JASC): [2310 · HF Communications System](https://openairdocs.org/jasc/2310)
- Part: Hf Comm
- Condition: Malfunctioned
- Location: Cockpit
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA1058025

## Discrepancy

HF1 RADIO RECEIVER IS GARBLED AND UNUSABLE ON 4 ATTEMPTS WITH DIFFERENT FREQUENCIES.  HF2 XMITTER AND RECEIVER NORMAL OPS.  HF1 HAD FADING ON SFO ARINC BUT WAS SOLID RECEIVING WWV UNABLE TO VERIFY DISCREPANCY.  REMOVED AND REPLACED HF NR 1 RECEIVER IAW MM 23 11 21 AS PRECAUTION.  VERIFICATION FLIGHT SUCCESSFUL.

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