four-wire

four-wire channel

[计] 四线信道

four-wire circuit

[计] 四线电路

four-wire extension line adapter

[计] 四线扩展适配器

four-wire line

[计] 四线制线路

four-wire line adapter

[计] 四线线路适配器

four-wire link

[计] 四线线路

four-wire multiplex facility

[计] 四线制多路复用设备

four-wire repeater

[计] 四线中继器

four-wire switching center

[计] 四线制交换中心

four-wire system

[计] 四线系统