AVI series audio/video composite multicores

New for this catalogue is a range of audio and video composite multicores for the broadcast and presentation industries. There are two types based around the Van Damme miniature coax and blue series studio grade audio multicore inner pairs; and one which uses Van Damme standard 75 Ohm coax for the video cores. These cables provide an elegant solution for the transmission of analogue audio and video signals from source to destination within the same jacket. The standard 75 Ohm type 268-375-202 has also been tested successfully with serial digital video over 50 metres.

Materials
Van Damme now use a higher purity oxygen free copper for the conductors - Ultra Pure Oxygen Free Copper. The use of this material further improves the ‘solderability’ and conductivity of the conductor resulting in faithful and transparent signal reproduction in use.

Audio pairs: Polypropylene (PP) is used for the conductor insulation. This material has a higher temperature rating than most polyethylene insulation giving excellent resistance to ‘shrink back’ during soldering. Its inherent hardness makes it ideal for the thin wall insulation used by Van Damme in their analogue audio multicores. This thin wall insulation ensures that the overall diameter of these cables is kept to a minimum without compromising electrical performance. Electrically it is very similar to polyethylene with a low dielectric constant (2.25 for PP solid types) and high stability across the lower frequency ranges associated with analogue audio signals.

Pairs are twisted together with a tinned UPOFC drain wire and shielded with an aluminium/polyester foil screen. The 150% coverage method employed ensures that the pair is fully screened and that the drain wire remains in close contact with the conductive aluminium foil allowing interference to be effectively taken to ground. These pairs are then overlaid with a flexible PVC composite jacket

Miniature video cores: Foam skin polyethylene is used for the conductor insulation. This special insulation is made up of individual pockets of inert gas suspended in polyethylene, resulting in a low dielectric constant and most importantly low capacitance. The skin refers to the outer layer of the insulation, which forms during the extrusion process. This skin is harder than the layer of insulation below it ensuring that the conductor is well protected. The dielectric constant of foam skin polyethylene remains stable over a wide frequency range, essential for transmission of digital signals. Other relevant properties include good stress and temperature resistance.

The insulated conductor is screened with 96% optical coverage bare oxygen free copper braid and overlaid with a special matt flexible anti kink PVC composite jacket. As with Van Damme standard 75 Ohm coax, the high density of copper conductors used in the overall braid provides an effective connection between the cable and the crimp ferrule of BNCs when terminated to give excellent screening and mechanical strength.

Standard video cores: The conductor insulation is polyethylene which has a low dielectric constant and is particularly stable across a broad frequency range. The dielectric constant of a material is a major factor in the cable’s low capacitance, while the stability helps maintain constant impedance. The type of polyethylene used also has a high crush resistance, which ensures that the cable’s insulator keeps it shape when flexed resulting in less variance in the characteristic impedance of the overall cable.

The insulated conductor is screened with 96% optical coverage bare oxygen free copper braid and overlaid with a special nonreflective anti kink PVC composite jacket. The high density of copper conductors used in the overall braid provides an effective connection between the cable and the crimp ferrule of BNCs when terminated to give excellent screening and mechanical strength.

Appropriate combinations of the above conductors are laid up with natural textile fillers and oversheathed with a flexible matt black PVC composite jacket.

Applications
• Transmission of analogue audio and video signals within one jacket
• Combinations to suit most video formats up to 5 coaxials for RGBHV/VGA
• Standard coax type proven with serial digital video up to 50 metres