What was found
NEITHER SATCOM NR 1 OR 2 TRANSMISSIONS COULD BE HEARD OR RECEIVED BY MEDLINK OR DISPATCH. SEVERAL ATTEMPTS/CALLS WERE MADE WITH BOTH SATCOMS. COULD HEAR THE PHONE CALL GO THROUGH AND COULD HEAR THE PERSON ANSWERING TALK TO US, BUT THEY COULD NOT HEAR US TALKING. ACFT GROUNDED. INSPECTED SATCOMS 1 AND 2. FOUND SYSTEM WORKING NORMALLY. PRECAUTIONARILY REPLACED SATCOM TRANCEIVER IAW AMM 23-15-00. ACCOMPLISHED SATCOM COMMUNICATION IAW AMM 23-15-00/501. SYSTEM CHECKS NORMAL.