收发话机 meaning in Chinese

voice transmitter receiver
voice transmitter-receiver

Introduction of the monophone - first hand set telephone of modern type
收发话机问世，这是一种款式新颖的手持电话。
Development of unattended private automatic branch exchanges . two - line monophones introduced
开发无人自动小交换机。二线制收发话机问世。
Commercial ship - to - shore telephone service opened . u . s . navy begins use of strowger equipment . monophones made available in color
商业轮船与陆地之间的电话业务开通。美国海军开始使用史端乔设备。彩色收发话机诞生。