Pbx private branch exchange switching equipment for voiceband application 话音频带用的专用支线交换机
2.
Private branch exchange switching equipment for voiceband application 话音频带用专用小交换机交换设备
3.
Telecommunications - network performance - point - to - point voice - grade special access network voiceband data transmission objectives 电信.网络性能.点对点话音频段专用访问网络话音频带数据传输目标
4.
In - line filter for use with voiceband terminal equipment operating on the same wire pair with high frequency up to 10 mhz devices 与高频最高10 mhz装置相同对绞线上运行的音频终端设备用嵌入式虑波器
