HDTV signals are made up of coded instructions - (the same 'bits' of 'ones and zeros' that make your computer work, and give life to 'CD's' and 'DVD's') - which are transmitted to your Digital Receiver, (aka: Tuner, Decoder or Set-Top-Box "STB") which in turn deciphers the code. A HDTV receiver isn't concerned with signal strength, or what conditions exist between your set and the transmitter. As long as the signal gets to the receiver, and the code can be read, the HDTV is able to reproduce a near-perfect picture - virtually identical to the original, back in the TV Studio.

A distinct advantage of digital broadcasting is that bad reception is a thing of the past. One reason Cable TV caught on is because it delivers clear TV pictures without regard to the viewer's location. Viewers don't have to be constantly adjusting the antenna in an attempt to "tune-in" a weak signal from a distant transmitter to get a clear picture. HDTV (DTV) eliminates the "snow" and "ghosting" caused by the weak signals from distant or blocked transmitting towers. If the analog television set does not receive a strong, undistorted signal from the tower, you will not get a perfectly clear picture.

Both digital and analog television signals weaken, the farther they travel away from the transmitting tower. On an analog TV, the picture slowly deteriorates from bad to worse as the distance between tower and receiver increases. However, the picture on a digital set will stay perfect until the signal becomes too weak for the receiver to distinguish between a (1) and a (0), at which point the image disappears completely.

This has been referred to as "the cliff effect" - the picture remains stable until it abruptly "drops off" the screen. This might be compared to sending Morse Code. As long as the person at the other end can make out the dots and dashes being transmitted they will be able to read the message. Once they lose the distinction between a dot and a dash they lose the message. HDTV acts the same way; instead of sending dots and dashes, it sends millions of (1's) and (0's) every second.

As long as the TV Receiver can read the (1's and 0's) it displays a virtually perfect picture. The bottom line ... you either receive a 100% quality image, or nothing at all. What this means to the digital television viewer, is not having to worry about getting a "bad" picture. Either you have a picture or you don't. However, if you are receiving over-the-air, "OTA" (Over the Air) broadcasts, it is crucial for the antenna to be accurately directed towards the signal source - the transmitting tower of the station you are watching.

We stated that DTV differs from NTSC-analog TV in the technology used to transmit the signal. And we looked at some of the reasons why Digital is better than analog. But when comparing HDTV or "SDTV" (Standard Definition TV) to HDTV, the difference is as night and day! High Definition Television is digital television BUT It's IMPORTANT to understand that HDTV does NOT mean HDTV! HDTV is just ONE of (18) ATSC designated formats that comprise HDTV. In High Definition Television, the picture displayed on your television screen begins as an HDTV signal captured by HDTV Cameras, (or converted from film or another format with HDTV Equipment). The HDTV Signal is transmitted to the HDTV Receiver and finally displayed on an HDTV-Capable TV Monitor. But it must also meet the ATSC Standards for High Definition Television in order for it to be "true" HDTV.

If what you want is HDTV, be sure the television you are considering, is really "True" High Definition Television. How Do you Know a TV is - HDTV? To answer this question a 'bit' of basic TV technology will be helpful.

The image you see on your television screen is comprised of a series of horizontal lines. An electron gun 'shoots' energy beams (light) which strike a layer of phosphor on the inside surface of the picture tube, causing it to glow. These glowing lines create the image displayed on your TV screen. How they are formatted, which resolution is used, what standards are met, are some of the factors that determine the type of television picture you will receive.