What was found
AIRCRAFT WAS RECEIPT AT GDL WITH CAPTAIN REPORT "VHF 1 OUT OF SERVICE", AS A CORRECTIVE ACTION BOTH VHF WERE REPLACED AN TESTED, ALL CORRECT. AIRCRAFT RETURNED OF FLIGHT AS A CONSEQUENCE OF VHF FAILURE CONTINUED. COAXIAL CABLE AND VHF NR 1 WERE CHECKED IAW MM 34-51-01, TESTED CORRECT. AS A PRECAUTIONARY ACTION, VHF NAV NR 1 CONNECTOR WAS REPLACED AND TESTED IAW MM 34-32-00.