What was found
TRANSMIT FUNCTION ON HF RADIO #1 COULD NOT BE HEARD BY SFO RADIO EXCEPT MAYBE 1-2 TIMES OUT OF APPROX 20 ATTEMPTS FROM BOTH PILOT STATIONS AND HAND HELD MICROPHONE, THE ONE OR TWO TIMES THEY COULD HEAR US ONLY POORLY AT 1 X 1, HF 2 XMIT OPS OK AND HF 1 RECEIVES LOUD AND CLEAR. GROUNDED - YES. PERFORMED BITE TEST OF HF #1, TEST PASSED PER B737-800 FIM 23-11 TASK 801, PERFORMED HF #1 SYSTEM TEST, TEST PASSED, TRANSMITTED & RECEIVED LOAD & CLEAR FROM BOTH CAPT & F/O SIDES. REF B737-800 AMM 23-11-00.