IEC 60169-9-1978
射频连接器 第9部分:外导体内径为3mm(0.12 in)的螺纹连接射频同轴连接器 特性阻抗50Ω(SMC型)
Radio-frequency connectors. Part 9 : R.F. coaxial connectors with inner diameter of outer conductor 3 mm (0.12 in) with screw coupling - Characteristic impedance 50 ohms (Type SMC)