视频: video frequency; vision freq ...拨号音: dial tone; trunk tone视频拨号音: vdt video dial tone; vdt video dial-tone; video dialtone视频拨号音服务: vdts video dial tone services; vdts video dialtone services视频拨号: video dialtone拨号音: dial signal; dialling tone; dt dial tone; dt dialing tone语音网关: ag audio gateway; voip单频拨号: one frequency dialing; single frequency dialing低频拨号: low frequency dialling话频拨号: vfd voice frequency dialing双频拨号: two-frequency dialling音频拨号: vfd voice frequency dialing; vfdial voice frequency dialing; voice-frequency dialing音频拨号器: tone dialer语频拨号: voice frequency dialing拨号音不断: non-stodial tone拨号音电键: dial tone key拨号音阶段: dial tone trunk拨号音延时: dial tone delay部分拨号音: partial dial tone长途拨号音: trunk tone二次拨号音: second dialing tone; secondary dial tone泛拨号音: partial dial tone没有拨号音: there is no dial tone数字拨号音: digital dial tone特殊拨号音: special dial tone
