Abstract: A field installable capacitor network assembly screws onto an externally threaded coaxial connector and makes contact with signal ground. The network assembly also makes a reliable low impedance contact with the chassis wall as it screws toward the coaxial connection, using protrusions extending from rear face of the network assembly to cut through any insulating coat covering of the chassis wall and make contact with the wall. A small capacitor inside a defined region of an annular body of insulating material secured between two sleeve shaped conductors respectively in contact with the connector and the chassis wall makes an electrical connection between these surfaces.