Video Cables

Ensure superior picture quality for your high definition TV with the right video cables

Video Cables

Video cables carry electronic signals from a video source, such as a DVD player or satellite TV box, to your television. In order to get top-of-the-line picture quality, the right cables must be utilized.

This guide highlights the different types of video cable options, picture quality and the materials used to make them.

Cable Types

To produce a picture with a particular screen resolution, you need 3 components:

  • A video source that generates the signal, a TV capable of displaying that resolution and a video cable that can transmit that resolution between the video source and TV.
  • Video interconnect cables fall into two categories, analog and digital video cables.
  • Analog cables transmit video as a continually fluctuating electronic signal, similar to an undulating wave.
  • The are four types of analog interconnect signals : Coaxial RF cable, which is the most basic type that can carry video signals up to 350i, which is lower than an analog TV signal, so there is a good chance analog cable will downgrade the signal from the video source,, Composite in the next step up from coaxial and can carry a 480i signal, which is adequate for analog TV, but will degrade high-def signals, S-Video can also carry signals up to 480i, but transmits brightness and color information separately., which delivers richer colors than composite cable, and Component, which is the most advanced type that can carry up to 1080p, which makes them a good choice for HDTV.
  • Digital cables transmit video as a series of 1s and 0s, the language of computers, which is much less susceptible to interference and degradation than analog cables.
  • For optimal conditions, it is best to use digital cables, especially if you have digital connections on your equipment.
  • There are 3 types of digital cables: High definition multimedia interface (HDMI) cables are the standard for digital cable and are the best connection available today. HDMI 1:3 can carry a 1080p video signal and eight channels of audio with bandwidth to spare, Digital visual interface (DVI) cables were originally developed for computers. They don’t transmit audio signals, but can be used if you want to use your TV as second computer, and FireWire, also known as iLink and IEEE 1394, is a connection technology designed to carry large amounts of data. They rarely are used to transmit HDTV signals, but some TVs have FireWire jacks which allow you to play video directly from some digital camcorders.

Video Cables

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Signal Quality

The video jacks on TVs have evolved to seven standard connection types for quality video signals

  • Screen resolution is the best measure of video quality, represented as the number of vertical scan lines displayed on screen. A scan line is made up of thousands of individual dots of light, called pixels, and the higher number of pictures equates to a higher screen resolution.
  • Video quality also depends on whether the picture is interfaced or progressive.scing elit
  • An interfaced picture generates half of the scan lines in one pass, skipping every other line, then generates the other half of the scan lines on the next pass. The resulting video has 30 full frames per second broken into 60 interfaced fields.
  • A progressive picture generates all scan lines simultaneously. It has 60 full frames of video per second ad is clearer and smoother than interfaced.
  • The seven resolutions are 240i- low resolution signal for VCRs, 480i- standard resolution for analog TVs and non-progressive DVD players, 480p- resolution of digital, non-HDTV signals and progressive scan DVD players, 720i- An HDTV signal resolution option, 720p- An HDTV signal resolution option, 1080i- An HDTV signal resolution option, and 1080p- the highest HDTC resolution.

Materials

High-quality materials do a better job filtering out interference than cables made of basic materials

  • Conductors are the wires inside the cable that actually carry the video signals. For best results, use cables with oxygen-free copper cable.
  • Shielding is the material that filters electromagnetic and radio frequency interference that can degrade video signals, so choose one with two shielding layers for best results.
  • Connectors are the part of the cable the plugs into a jack. Choose one with gold-plated connectors for best results.
  • Outer jacket is the cord cover that provides protection from cuts and scratches.