把信号的一种频率转换为另一种频率的电讯装置。
An electronic device that converts one frequency of a radio signal to another.
电讯：天线，微波放大装置等；
托盘式电缆桥架是石油、化工、电力、电视电讯等方面最广泛应用的理想敷设装置。
Tray - cable bridge is the most extensive application of the ideal laying devices to oil, chemicals, electric power, telecommunications and television.
1874年他发明并售给西联电讯公司一种装置，用了它可以在一根电线上拍发四份电报，即从每一方向可同时拍发两份电报。
In 1874 he invented and sold to Western Union a system by which four messages could be sent over one wire at the same time, two in each direction.
1874年他发明并售给西联电讯公司一种装置，用了它可以在一根电线上拍发四份电报，即从每一方向可同时拍发两份电报。
In 1874 he invented and sold to Western Union a system by which four messages could be sent over one wire at the same time, two in each direction.
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