程控电话交换机 Digital Telephone Switch Board ; NEC ; PCS----program control switches

电话程控交换机工程师 PBX Field Engineer

程控数字电话交换机 SPCDTSSstored program colled digital telephone switching system

数字式程控电话交换机 digital program-controlled switching ap-paratus

程序控制电话交换机 Program controlled telephones switching system