As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RT HF TUNING. DUE TO CHRONIC REPORTS OF RT HF RADIO WILL NOT TUNE, PERFORM THE FOLLOWING TASKS. COUPLER MR23167-10 WAS INSTALLED ON 8-26 AND HAD PREVIOUS HISTORY FOR SAME PROBLEM. PREVIOUS PROBLEM ON THIS AC WAS RECEPTION. TUNING PROBLEM ONLY APPEARED AFTER INSTALL OF THIS UNIT. REPLACED THE RT HF COUPLER IAW AMM 23-11-03. REPLACED RT HF COUPLER REF AMM23-11-03, OPS CHECKS NORMAL.