My experience for the first time doing Maritime mobile at South China Sea approximately at Latitude: 4.609833 Longitude: 104.8125 travelling by fishermen small ship more than 8 hours. The deep sea fishing has been planned early 2018 and incidentally the date are the same with Field Day event by Malaysia Amateur Radio League (MARL). So I brought along my home brew HF 40 meter band (called as JJ from Bandung) with mobile home brew mobile antenna given by YB0OO. After given permission by boat captain, I manage to QSO with several Field Day stations and YB land station with 5 by 9. Unfortunately sea waves quite high between 2 to 3 meters high unable to proceed with fishing activity.