SF system: Ocean cable and couplings

An SF armorless coaxial cable design having lower loss than its predecessor, the SD design, has been developed. Its basic construction is similar to that of the SD Cable. However, its larger diameter, along with lower loss polyethylene and higher conductivity inner conductor copper, provides a substantial decrease in attenuation. A new coupling design has also been developed. The armorless version of the coupling design provides an improvement in return loss between cable and repeater and smaller deflection of the plastic parts under load. The armored version of the coupling provides improved isolation of the steel and beryllium copper parts.