Electronic connectors and cable assemblies are used for communications and data transfer applications as well as for power connections. The insulative body around the contacts or feedthroughs often needs to be protectively sealed with potting agents for use in harsh environments. Plasma cleaning and activation ensures a complete hermetic seal of the potting material around the electrical contacts or feedthroughs. Manufacturers of cables (both round and flat) are using plasma to treat the insulation on the cable before potting the cable end into the connector. This provides both a better hermetic seal and a stronger physical connection between the cable and the connector. Plasma has been used successfully on jackets of polyester, silicone rubber, Kapton(tm), and Teflon(tm).