IEC 60169-21:1985/AMD1:1996
IEC 60169-21:1985/AMD1:1996 Amendment 1 - Radio-frequency connectors. Part 21: Two types of radio-frequency connectors with inner diameter of outer conductor 9.5 mm (0.374 in) with different versions of screw coupling - Characteristic impedance 50 ohms (Types SC-A and SC-B)
