双音: double tone双: two; twin; both; dual频: frequent信号: signal; semaphore; gun双音双频音信号方式: touch tone signaling双频信号: two frequency signal; two-frequency signal双音多频信号: dual-tone multifrequency signaling双频信号方式: two frequency signaling双频信号发生器: diplex generator; two-frequency signal generator双音多频信号接收器: touch down point双频信标: double frequency beacon; dual-frequency beacon双音多频信令: dtmf dual tone multifrequecy signaling双音频（信号）调制: ttm two tone modulation双音信号法: two tone method双频制信号: two-frequency signallingq视频信号: q video signal半频信号: half-frequency signal泵频信号: pump signal; pumping signal单频信号: simple signal导频信号: pilot signal; pilotsignal调频信号: fm signal; frequency modulated signal; frequency modulation signal; frequency-modulated signal多频信号: multifrequency signal多频信号制: multifrequency signalling system高频信号: high frequency signal; high-frequency signal镜频信号: image frequency signal
