Communication Today

Tech Talk – HD

Q – If Orbitel offers 100% digital television, does that mean all the channels are high definition?

A – Digital television refers to the method by which the TV signal is encoded. Digital television offers higher resolution and less interference than the old analog TV system. Both standard definition (SD) and high definition (HD) signals can be transmitted digitally.

Orbitel offers both standard and high definition channels in digital.

The primary difference between SD and HD is picture quality. Even though both are digital channels, HD signals use approximately five times the data of standard definition signals to make up the TV picture. HD pictures are generated with more pixels and more horizontal scan lines than SD, making the HD signal crisper, clearer and more brilliant.

In addition, SD and HD have different aspect ratios. The aspect ratio of an image describes the proportional relationship between its width and its height. It is commonly expressed as two numbers separated by a colon. The SD TV picture is transmitted in a 4:3 aspect ratio (more of a square) while HD is transmitted in 16:9 aspect ratio (more of a rectangle). The 16:9 aspect ratio more closely approximates human sight.

To view a channel in HD you must first have an HDTV set. You must then tune to the HD version of the channel you want to watch. If you are using an HDTV set and tuning to an SD channel, you will see black boarders down the left and right sides of your screen because the aspect ratio of the SD signal is 4:3 and the aspect ratio of your TV set screen is 16:9. Likewise, if you view an HD channel on a standard definition TV set, you will see black borders along the top and bottom of your screen so the 4:3 TV screen can show all of the 16:9 picture.

Orbitel has recently added over 60 new HD channels, making a total of more than one hundred HD channels available! They begin at 802 and are grouped thematically so similar channels are next to one another in the lineup to enhance your viewing experience. The HD channels begin on channel 802. Any channel that you can access in SD on Orbitel that has an HD version will be accessible to you with an HDTV set and an Orbitel HD converter box.

Contact a local Orbitel representative today to learn more at 480-895-8084.