About RFI and EMI - Contacts, Fingerstock and Gaskets
Fingerstock and gasket contacts are components utilized to mitigate electromagnetic interference (EMI), also known as radio-frequency interference (RFI) when it occurs within the radio frequency spectrum. EMI can negatively impact electrical circuits through electromagnetic induction, electrostatic coupling or conduction. These contacts are employed in situations where parts or doors of a chassis or enclosure are removable, rendering them vulnerable to EMI. To attach these contacts, various methods can be used, including adhesive, clips, hardware, solder, slotting or snap-in channels. The choice of attachment method is dependent on the specific requirements of the application and the materials involved. Fingerstock contacts consist of conductive metal strips that are shaped in a "U" or "V" shape, forming a spring-like structure when mounted onto a surface. These contacts allow for effective grounding and shielding against EMI by creating a conductive path between two surfaces while maintaining a low impedance connection. Gasket contacts, on the other hand, utilize conductive elastomer material or metal mesh that is installed between two surfaces. This material creates a tight seal that prevents EMI from passing through the gap between the two surfaces. Gasket contacts are commonly used in applications where environmental sealing is required, in addition to EMI protection. In summary, fingerstock and gasket contacts serve as critical components for limiting electromagnetic interference (EMI) in electrical circuits. With their different construction and attachment methods, they offer effective grounding and shielding capabilities that preserve signal integrity and ensure reliable system operation.
