Comb filter - A circuit in NTSC sets that separates the color information from the brightness information.
CRTC - Canadian Radio-television and Telecommunications Commission, the federal regulatory body for television programming and broadcasting in Canada.
Down Converting - Process by which a high-definition signal is converted to a standard definition picture.
Aspect Ratio - the ratio of image width to image height. The term may apply to the display device configuration, or the shape of the content being displayed. (See Letterboxing) HDTV uses an aspect ratio of 16 units wide by 9 units high. Conventional television programming and displays are at an aspect ratio of 4 - 3. Digital SDTV programs may aspect ratios from 4 - 3 to 16 - 9, dependant on content and its source (e.g. upconverted NTSC is likely to be 4 - 3).
Letterbox - The full display of a wide aspect ratio 16 - 9 picture on a display of aspect ratio 4 - 3 will result in black bars above and below the picture. This arrangement is referred to as "Letterbox" and is often seen during movies shown on television.
HDTV - (High Definition TV) - A TV that displays 1280x720 pixels or better.
Pan-and-scan - A method of broadcasting a wide screen film on a 4:3 channel. Most of the time just the center of the image is shown. (The right and left edges are clipped off.)
DTS - Digital Theatre Sound System. A Dolby proprietary discrete 5.1 channel surround system similar to, but not the same as Dolby Digital AC-3, the DTV standard. DTS is used in cinema presentations and in DVD's.
Interactive Television - TV programming with interactive content and enhancements, blending traditional TV viewing with the interactivity of a personal computer.
Over-the-air Broadcast (OTA) - Also called Terrestrial Broadcast. The delivery of TV and radio signals, using UHF/VHF frequencies, directly to consumer devices. Broadcasts may be either analog or digital.
C-band / Ku-band. - 1. a range of RF spectrum. C-band is app. 4 GHz. Ku-band is app. 12 GHz. 2. Geo-stationary satellites the networks use to acquire and distribute programming to affiliates and cable TV companies. These satellites use C-band and Ku-band frequencies. 3. a consumer service that uses the satellites the networks originally set up for themselves. An 8-foot steerable dish is required. Some channels are free. Others are available by subscription. The digital channel subscription service is called 4DTV.
Convergence - An adjustment that must be made occasionally to CRT sets. This adjustment makes the three colors coincide perfectly.
Fire-wire - (see IEEE 1394)
HD-Ready TV - An HDTV monitor or TV that lacks a digital tuner.
LCOS - (Liquid Crystal On Silicon) - This is another contender to replace CRTs in projection TVs.
MTS - (Multi-channel Television Sound) - This refers to an analog NTSC TV equipped with stereo and SAP (separate audio program) features.
Resolution - The level of resolution directly affects picture quality. The higher the resolution, the more picture detail there is. Many things affect picture quality, including number of bits, pixel count, format, receiver quality, cameras, lenses and lighting used for live or taped programming. Resolution is measured by the number of pixels displayed. One of the high-definition picture formats is composed of 1080 active lines, and each line is composed of 1920 active pixels. Therefore, each frame has over 2 million (1080x1920=2,073,600) color pixels creating the image. By way of contrast, today's typical analog television is roughly equivalent to 480 active lines, with each line holding about 440 pixels. So, each frame has a little over 200,000 color pixels in use creating the image.
Set-top Converter Box - This unit sits on top of the viewer's analog TV, receives the Digital TV signal, converts it to an analog signal, and then sends that signal on to the analog TV.
