As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HF NR 1 UNABLE TO TRANSMIT FROM EITHER PANEL AND NO SIDETONE. RECEIVES NORMALLY. ACFT GROUNDED. REMOVED AND REPLACED THE NR 1 HF ANTENNA COUPLER IAW AMM TASK 23-11-61, GROUND FUNCTIONAL CHECKED NORMAL WITH GOOD SIDETONE AND VOICE. PULLED AND RESET 2 TOTAL CIRCUIT BREAKERS.