VGA Cables for AV Cable Kits

VGA Cables for AV Cable Kits

Cable design parameters can be selected based on cost and/or performance criteria.

Cables for cable kits, as opposed to single cable purchases, are nearly always used in fixed installations where the position of the projector is also fixed. This is a little different to the situation where a table top projector may be connected to different computers and at a different distance from the screen each time it is used. The question is whether or not a fixed installation needs DDC ie extra wires in the VGA cable used to automatically adjust the picture qualities (could consider omitting DDC for fixed PC installations and include where laptops or notebooks are used).

Another consideration is when and where to use ferrite beads to prevent Radio frequency and Electromagnetic intererence. Ferrite beads should be used at either end of a VGA cable run. So in the case of the cable kit a ferrite bead should be fitted to the VGA cable at the projector end. (The computer should be connected to the cable kit using a short VGA cable with a ferrite bead at the computer end of the cable)

The next question is whether the Horizontal sync and Vertical sync wires should also be coaxial pairs, the same as the Red Green and Blue (RGB) coaxial pairs ie whether to use 3 coaxial pairs or 5 coaxial pairs.

And lastly the screening of the overall cable should have sufficient integrity to prevent interference, this is often measured in "percentage cover" of the braiding or drain wire and foil. Braiding alone would normally have less than 100% cover and can be replaced by a drain wire and a foil which "covers" the gaps 100%.

These cable design issues affect the electrical performance of the overall system, usually seen as "ghosting" in the projected image, remembering that performance is also affected by the length of the cable, connection mismatches, device output levels and the set-up of equipment etc

Cable can also be supplied terminated at one end or both ends. Usually cables can be installed with both ends terminated especially when installed in surface trunking. The time taken to terminate a cable on site far outweighs the extra cost of a connector. When cables need to be threaded through conduit or small diameter holes we would recommend cutting the VGA connector from one end and re-terminating the cable using a screw terminal or crimped ferrule connector.

You have a choice of VGA cables with 3 or 5 coaxial pairs with and without DDC wires and with and without ferrite beads and with one or two connectors to suit your customers needs and price expectations. Others supply these various designs but most do not offer a choice of cable design with their AV cable kits, with our options you can choose to compete on price, performance or both!

Typical Edis VGA cable designs

Construction		Length (m)		Ferrite Bead		Colours		Sheath		Connector
3 Coax + Sync + DDC		1.5, 3, 5, 10, 15		With/Without		Blk, Grey, White		PVC/LSOH		Straight/90 Degree
5 Coax		1.5, 3, 5, 10, 15		With/Without		Blk, Grey, White		PVC/LSOH		Straight/90 Degree
5 Coax + DDC		1.5, 3, 5, 10, 15		With/Without		Blk, Grey, White		PVC/LSOH		Straight/90 Degree

See also ...

• "VGA cables and connectors for projectors and monitors"
• VGA Connections
• Length of Cables for AV Systems in a School Classroom