Coded transmission manner null of fish finder

摘要

PURPOSE:To decrease a transmitted information content of a fish detection image. CONSTITUTION:After fish detection image information is given weight with marker pulses Al to A4 corresponding to each sampling while sampled a plurality of times per unit signal content along a time axis T by a CPU 22, this fish detection image information is made the Morse code with a coding circuit 25 together with marker pulses A1 to A16, and is transmitted from an antenna 13 to a display element 15 by a transmitting circuit 26. In the display 15, each sampled fish detection image information is synthesized on the basis of the marker pulses A1 to A16 by a CPU 17.