IEC / EN 61000-4-6 specifies the design and performance of a range of coupling /de-coupling networks (CDNs). Each CDN is specific to the type of cable and the intended signal carried on the cable. AMETEK CTS with its brand TESEQ offers an extensive range of CDNs which fully comply with the requirements of the standard and provide a simple and reliable method of injecting RF energy into the equipment under test (EUT). In this datasheet, CDN used with unscreened unbalanced for data communications with different line application starting from 10 kHz as required by NAMUR NE21 is presented. The shown CDN AF series is used to Inject common mode disturbance signal into unscreened and unbalanced control lines with low currents in the frequency range from 10 kHz to 80 MHz.