Dielectric / Insulation Material
Cable dielectric material is the insulating material between conductors that also affects the cable’s electrical behaviour.
Examples include polyethylene and PTFE in specified constructions. The dielectric is distinct from the outer protective jacket and from a decorative braid.
Dielectric / Insulation Material — BNC Cable
In a BNC coaxial cable, the dielectric separates the centre conductor from the surrounding conductor. Its properties, together with conductor dimensions and spacing, contribute to characteristic impedance and capacitance.
Compare the specified cable impedance and other electrical measurements alongside the material name. A particular dielectric alone does not establish a 75-ohm assembly or guarantee better audio performance. Keep foamed and solid constructions distinct where stated, and do not identify the internal dielectric from the appearance of the outside jacket.