トーン信号発生機能の周波数範囲 - DTX CableAnalyzer The frequencies in Hz are: #define FI_A 440 #define FI_As 466 #define FI_B 494 #define FI_C 523 #define FI_Cs 554 #define FI_D 587 #define FI_Ds 622 #define FI_E 659 #define FI_F 698 #define FI_Fs 740 #define FI_G 784 #define FI_Gs 831 The three digit number is the frequency. For example, FI Gs 831 is 831 Hz.