As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HF1 XMIT WAS NOT RECEIVED BY ATC. RECEIVED TRANSMISSIONS FROM ATC ON HF2. GROUNDED - YES. REMOVED AND REPLACED #1 HF ANTENNA COUPLER IAW B737-800 AMM 23-11-61/401. INSTALLATION TESTED NORMAL. VERIFIED #1 HF TRANSMIT AND RECEIVED NORMAL. REMOVED MEL 23-11A.