This part of IEC 60512 specifies the test methods for transmission performance for IEC 60603-7 series connectors up to 500 MHz. It is also suitable for testing lower frequency connectors if they meet the requirements of the detail specifications and of this standard. The test methods provided here are: - insertion loss, test 27a; - return loss, test 27b; - near-end crosstalk (NEXT) test 27c; - far-end crosstalk (FEXT), test 27d; - transverse conversion loss (TCL), test 27f; - transverse conversion transfer loss (TCTL), test 27g; For the transfer impedance (Zt) test, see IEC 60512-26-100, test 26e. For the coupling attenuation, see IEC 62153-4-12.