PURPOSE: To prevent the indication of a wrong signal and reduce labor, by identifying the location of a ship on the basis of chart data stored in a memory and input values from a radar, a gyrocompass and a ship speed measuring instrument, to automatically send out a signal required in the area where the ship is.

CONSTITUTION: The location of a ship is identified on the basis of chart data 22 stored in a memory 20 and input values from a radar 26, a gyrocompass 29 and a ship speed measuring instrument 30, to automatically send out a signal required in the area where the ship is. When it is judged from the signal of a solar switch circuit 27 that it is daytime, a figure such as a signal flag is displayed on a CRT25. When it is nighttime or the visibility is low, a signal light switch-on/off circuit 23 is automatically controlled. According to this constitution, a wrong signal is prevented from being indicated, and signaling labor is reduced.