KS C IEC 62255-3-1-2014(2019) 宽带数字通信用多芯对称对/四芯电缆(高速数字接入通信(高速数字接入通信)空白详细规范
Multicore and symmetrical pair/quad cables for broadband digital communications(high bit rate digital access telecommunication communications(high bit rate digital access telecommunication Blank detai