SDTV - "Standard Definition Television." SDTV are based on 480 lines of vertical resolution and may have either 4 - 3 or 16 - 9 aspect ratios, and surround sound. Several SDTV programs are sent together to form the simulcast bundle. While SDTV pictures are of significantly better quality than NTSC, they are not up to the standard of HDTV.
Comb filter - A circuit in NTSC sets that separates the color information from the brightness information.
Fire-wire - (see IEEE 1394)
HDTV - "High-definition Television." This is the most superior video picture available in Digital TV. In the U.S., the 1080i and 720p formats in a 16:9 aspect ratio are the two acceptable HDTV formats. HDTV is a component of DTV.
STB - (Set Top Box) - These include satellite receivers, cable TV receivers, OTA receivers, and various recording devices.
YPrPb - Color representation requires three independent variables. CRTs - prefer red, green, and blue. Ink jet printers prefer yellow, magenta, and cyan. NTSC encodes color as luminance (brightness), hue (color), and saturation (absence of white in colors). Storage media such as DVDs prefer Y, Pr, and Pb, where Y is luminance, Pr is Y-red, and Pb is Y-blue. This is because Pr and Pb can be at lower resolution and not degrade the image noticeably, thus saving storage space.
LNB - (Low Noise Block converter) - An LNB can be found at the focus point of a dish antenna. It is a low noise amplifier that also converts the signal to a lower frequency. (The original higher frequency would not travel very far in ordinary coaxial cable.)
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.
