To evade a difficulty for producing a multi-level waveform, and produce the multi-level waveform more simply by using a simple switching pulse generating device without a power amplifier by a simple constitution technique.

The subject is solved by the method for producing the multi-level transmission waveform having a step for producing a first voltage level responding to a first switch, a step for producing a second voltage level responding to a second switch, and a step for outputting one transmission waveform having at least three different non-zero peak amplitudes from a first transformer depending on time and responding to the two steps.