As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HF RADIO #1 RECEIVES BUT WILL NOT TRANSMIT,TRIED MULTIPLE FREQUENCIES. HF RADIO #2 OPS NORMAL. GROUNDED - YES. PERFORMED B737-800 FIM 23-11 TASK 806 & PERFORMED HF BITE REFERENCED FIM 23-11 TASK 801. NO FAULTS NOTED. VERIFIED HF #1 TRANSMITS NORMALLY.