Dielectric binding is applied over the twisted individually insulated conductors, arranged in a particular pattern, and therefor multiplies cumulative dielectric attributes of the cable composition. SDB (Standard Dielectric Binding) is a 2-layer bi-directional X-Cross PTFE tape overlaying process. It is currently incorporated in some Special cables.
SASDB® (Semi-Air-Spaced Dielectric Binding, patent RU No.144590U) is a 4-layer bi-directional X-cross non-polar PTFE tape overlaying, where each successor winding of the 3 opposite inner layers is set with an air gap and the bonding layer completed with a 30% overlay. With SASDB® signal energy loss is further decreased thanks to the solid material being partially replaced by air spacing, with extremely low and frequency independent relative permittivity. Furthermore, due to the ease of mechanical interlayer tensions, vibrations are absorbed efficiently and better flexibility is obtained. The uppermost version of SASDB® with the bonding cotton tape layer is used in Reference & Ultimate cables.
