| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To make a tuner which picks up an instrument sound by a microphone and a metronome which radiates a beat sound by a speaker operate normally in the same case at the same time. <P>SOLUTION: The instrument sound to be tuned is transduced by the microphone into an electric signal, which is saturation-amplified to generate a rectangular wave; and time data are obtained each time the rectangular wave crosses the zero level, fundamental cycles of the instrument sound are extracted from the time data, and the pitch name of the instrument sound and an error from a reference pitch are displayed. This tuner is inhibited to acquire data while the metronome is sounding to eliminate the influence of the sound caused by the metronome. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
