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话说数字电视(Digital TV)(下)
作者:home99
发表时间:2015-12-25
更新时间:2015-12-25
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这部分主要是一些英文的资料,贴这里与大家分享与学习啊,呵呵。

●免费网络电视Internet TVFAQs
●小米盒子常见使用问题解答
●How to survive the digital TV transition
●10 things you need to know about Digital TV Antennas
●FAQ: What does the digital-TV switch actually mean?
●What's the difference between a DVR and a PVR?
●The Complete PVR Buying Guide
●DTV Glossary

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免费网络电视Internet TVFAQs

◆ 什么是Freeview TV和Freesat TV?
◆ 什么是网络电视Internet TV和IP电视?
◆ 收看免费网络电视必备哪二个条件?
◆ 英国免费网络电视服务有哪几类?
◆ 哪国网络电视消费世界第一?
◆ 为什么英国网络电视用户比率世界之最?
◆ 看网络电视需要购买TV Licence吗?
◆ 网络电视,电视的未来吗?

◆ 什么是Freeview TV和Freesat TV?

网络电视Internet TV,顾名思意,是通过网络传输数字电视节目的电视服务。包括免费和付费两种。它能在任何能接收到网络的设备,诸如电脑、笔记本电脑、平板机、游戏机、智能手机上直接收看,也能连接到电视机上收看。用户或直接到网络电视供应商的网站注册收看,或下载网络电视软件到电脑桌面上随时点击收看,如中文的PPS、PPLIVE。网络电视收看成本最低,是数字化革命深入后电视的未来。

IP电视,全称为因特网协议电视(Internet Protocol television)。它属网络电视的一种,但不同的是它处在持续进行标准化(欧洲电信标准协会)和更先进的部署方案中。即在以用户为基础的收费网络中,通过特定的机顶盒或电视棒等其它设备让用户高速登陆收看既定的电视频道服务。IPTV服务可分以下三组: 直播电视live television: 与现有电视节目有的拥有交互性;时间变动电视(time-shifted): catch up—回放重播几个小时或数天前的电视节目; start-over 从头开始重播电视节目;视频点播video on demand(VOD)—从目录中浏览和选择视频节目。您可以在自己方便的时间、地点,收看过去数天内的喜爱节目,可以一口气将喜爱的一套电视剧看完。

网络电视是网络时代的必然产物。与传统的电视服务相比,它根本打破时间、空间局限,让收看电视变得更舒适方便、内容选择更自主,当然成本也更低甚至完全免费。随着英国高速固定网、高速移动网、WiFi网的普及,以及平板电脑、智能手机的普及,IPTV必将得到更大的发展,占有越来越大的电视市场份额。

◆ 收看免费网络电视必备哪二个条件?

收看网络电视必备二个基本要素:其一:宽带网,这是得到网络电视服务的首要关键。注意,网速至少要2MB以上才能确保您看到流畅、清晰的电视画面。同时,如果您经常性收看网络电视,最好选择允许无限下载的宽带项目,以避免产生额外的费用。其二:具有网络功能的数字化设备,如台式电脑、笔记本电脑、平板机、游戏机、智能手机等。设备内存、硬驱、操作系统等配置的优劣也会影响到收视效果。有高速网和高效智能机就有一切,正是越来越明确的事实。

◆ 英国免费网络电视服务有哪几类?

收看网络电视非常容易!高速网络就是信息高速公路。这条公路不仅仅开启了传统电视供应商新的供给模式,也让宽带供应商理所当然成为主要电视供应商,广播电视公司更是积极踊跃。目前网络电视服务主要有如下三类:

一是传统电视供应商SKY和维珍媒体提供的网络电视服务。只要选择它们的电视套餐,就能在传统电视服务之外获得免费的网络电视服务。

二是英国电信、TalkTalk等二大宽带网供应商提供的网络电视套餐YouView。
三是BBC、ITV等广播电视公司提供的广受欢迎的BBC iPlayer、ITV Player、Channel 4's 4oD等,登陆其网站,注册就可随时收看,还可下载。BBC iPlayer是网络电视服务的最出色代表。它节目丰富,制作精良。有在线直播,也有节目随时回放。

四是以Youtube为代表的与用户互动性极强的视频服务。内容异常丰富、更新即时,而且与用户互动性强(可下载上传),使用者遍及世界,在英国更是登陆最多。这类网络视频服务数不胜数。在英国的华人普遍喜爱PPS、PPLIVE中文网络电视服务。

◆ 看网络电视需要购买TV License 吗?

看网络电视,您不需要购买TV License。只要您没有收看或记录电视上正直播的节目。这意味着如果您只使用电视回放服务,不看直播的节目,1年就能省160镑。然而,您应该认真考虑没有TV License 的犯罪风险。

◆ 哪国网络电视消费世界第一?

2012年末,英国电信总局公布的最新调查报告显示:每周至少有23%的英国宽带用户,通过网路收看电视节目直播或节目回放(Catch up)!这个比率数字,远远领先于其它国家,包括电视普及率最高的美国。

在调查表上,美国网络电视用户位居第二,为17%。西班牙位居第三,为16%。报告也透露,英国人每天收看电视节目的时间平均为242分钟。与之相比,意大利为253分钟,美国为293分钟。

◆ 为什么英国网络电视用户比率最高?

英国飞龙电信顾问认为主要有如下四点要素:
其一:传统因素。痴迷电视是这个国家的传统。英国电信总局负责人称:'英国一直是世界上最爱看电视的国家。'这种痴迷是英国广播、影视制作业发达的肥沃土壤。

其二:高速网与网络接收设备—这两个网络电视发展的硬件,近几年在英国发展迅速而且相对均衡,这必然造就出发达的网络电视服务和庞大的消费群。近几年,一方面固定网、移动网、公共WiFi网在英国迅速普及和速度提升,从最高2MB攀升到现在的最高160MB。另一方面作为数字化革命成果的智能电视机、平板机、智能手机等从稀有之物成为现在的普及品。根据电信总局的新统计:英国家庭拥有智能电视机的比率大约为15%,拥有HD电视机的比率大约为41%的家庭。这个数字只略低于美国。这两者给超越时空局限的移动电视装上了飞翔的翅膀。

◆ 网络电视,电视的未来吗?

21世纪初开始的英国高速宽带革命已将英国带入网络电视的时代。所有的迹象已表明,在'网络即生活'的时代,网络电视正成为、也必将成为主要的收视模式。因为它更符合现代人的生活方式和生活节奏。您的脚迈到哪,电视服务就在哪!。

网络电视将我们从电视节目单上前所未有地解放出来了!定时坐在电视机前苦苦等待自己喜爱的节目,这样的时代已过去了!面对着这样清晰的现实和未来,宽带供应商、广播电视制作商、网站设计者、各行各业的商家们,都一齐行动了。

我们可以按需要,在电脑、电视机、笔记本电脑、智能手机、游戏机等设备间,任意切换收看屏幕。我们可以免费收看丰富的电视节目,也可以多房间共享电视服务…… 多种数字化工具都能帮助我们。

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小米盒子常见使用问题解答

小米盒子是一款高清互联网电视盒,用户可通过小米盒子在电视上免费观看网络电影、电视剧,同时能将小米手机、iPhone、iPad、电脑内的照片和视频通过WIFI投射到电视上。但是你真的完全会使用了吗?小编收集整理了一下关于小米盒子使用中的常见问题进行了整理,希望对大家有所帮助。

Q:小米盒子是什么,有哪些功能
A:小米盒子是由小米公司出品的高清互联网电视盒,是小米手机迄今为止最发烧的配件。通过小米盒子,可以做到:
1.在电视上看网络视频,电影、电视剧、动画片以及综艺节目等;
2.在电视上玩游戏,已有植物大战僵尸、宝石迷阵等游戏;
3.在电视上听音乐,已有豆瓣电台、多米音乐;
4.可以将小米手机、iPad、iPhone、iTouch及支持DLNA终端设备上的图片、视频投放到电视上,并将手机作为遥控器进行操作;
5.借助OTG的功能将U盘,移动硬盘内的本地高清影片直接通过盒子在电视上进行播放。

Q:新小米盒子的配置参数
A:新小米盒子在处理器方面仍采用Amlogic的产品,只是由原来Cortex-A9架构主频800Mhz升级为Cortex-A9架构主频1.5GHz双核,并支持蓝牙3.0和2.4GHz/5GHz双频无线网络。此外,遥控器也升级为与小米电视相同的11键极简遥控器。

Q:买智能电视还是新小米盒子好?
A:当然买盒子,智能电视第一贵,第二系统比较死,不方便升级,不好玩。而盒子是标准android设备,可以深度挖掘其潜力,不但软件方便升级管理和修改,这几天小米盒子2出了,直接换硬件,成本也就几百块而已。盒子完胜!

Q:小米盒子能直播电视了吗
A:小米盒子本身没有直播,需要借助第三方带直播的软件。论坛用户使用最多的是泰捷视频,对小米盒子兼容性好,拥有500+直播频道,并支持自定义频道。软件下载:泰捷视频

Q:如何才能让盒子默认启动就是看电视直播的
A:开机自启动功能多由软件来实现。比如泰捷视频自带开机启动直播的设置,可在泰捷视频设置板块对直播进行设置。

Q:小米盒子需不需要越狱?
A:如果我们对越狱理解一致的话,应该叫root,取得设备的最高管理权限。那么,不需要。以前需要安装任意一个第三方桌面软件,即可突破小米盒子自身无法调用第三方软件的限制。现在新小米盒子采用了最新的系统可以不通过第三方桌面即可安装直播软件。比如泰捷视频,有600+直播频道。

Q:老的OTG还能在新小米盒子上使用吗
A:新小米盒子虽采用了方形USB接口,但老的OTG线可通用。新小米盒子配的新OTG线不能在老盒子上使用。

Q:小米盒子可以装手机上的安卓软件吗?
A:理论上所有安卓应用都可以装。但由于小米盒子自身的限制(没有TF卡槽,遥控器操作的方式),所以不是所有软件都可以完美运行。经实测,配合无线鼠标或小牛遥控可以运行的有“善听”(不能下载)、“墨迹天气”、“哔哩哔哩”、“手机QQ2013”(不能收发文件、照片)、远程桌面、网易新闻(无图版)、UC浏览器HD(完美运行)、ES文件管理器(完美运行,遥控器也可操作)。完全不能用的软件有“布卡漫画”、“快牙”等需要SDcard设备(TF卡)的应用。

Q:新小米盒子装了应用,有些是横着屏幕的怎么解决?
A:安装软件请认准TV版,手机版和PAD版的软件有可能出现不是全屏或竖屏显示的情况。

Q:盒子能重刷系统吗
A:抱歉,现在只可以进recovery里三清。官方没有发布刷机包的。
Step 1. 断开盒子电源。
Step 2. 同时按住遥控器"主页" "菜单",然后连接电源(连接电源时请勿松开"主页键" "菜单键")
Step 3. 按住遥控器"主页" "菜单",直至出现图中画面,松开按键。
Step 4. 选择第三项"wipe data/factory reset"选项:
Step 5. 选择后会出现以下选项,选择"Yes -- delete all user data."
Step 6. 等待系统删除数据,并重新出现选择界面。选择第一项"reboot system now"
Step 7. 选择 reboot to system two 等待盒子自行重启即可。
注明下:reboot to system one 是恢复到升级前的系统.
reboot to system two是恢复到升级后的系统

Q:新小米盒子为什么要ROOT?
A:作为一个安卓设备,将系统ROOT后有以下好处:
1 、可以软关机软重启,不用对小米盒子的待机纠结了
2、可以整机翻墙,对于盒子来说,YOUTUBE ,我不多说 该懂的就懂 。。。
3、 可以安装 百变遥控服务端,用手机模拟无线鼠标和无线键盘。比小牛遥控强大。广大不支持遥控器的安卓应用就靠他们了
4、 可以删除不需要的系统应用
5、可以映射虚拟SDcard,突破限制玩转各种应用。
6、ROOT本身就代表无限可能,无ROOT,不发烧。
希望小米早日发布官方ROOT包。

Q:新小米盒子发热厉害吗?
A:新小米盒子除了在硬件上做了一些升级外,外观、散热等未作出改变。小米盒子的设计比较特殊,为了防尘,干脆没散热孔,也就没采用一般的风扇冷却方式。发热比较严重,建议不要放遮尘布之类影响散热的东西,并且在盒子上加装其他散热方式,比如散热风扇等。

Q:小米盒子的软件推荐
A:用“系统设置”APK管理盒子应用。文件浏览器选ES文件浏览器。看直播点播,用泰捷视频TV版。娱乐软件,多米音乐、虾米音乐TV版等。

Q:小米盒子IOS7的aiplay无法使用
A:据说ios7投屏问题,苹果那边改变了一些机制,目前还没有具体的解决办法。等待小米盒子工程师在后续版本中解决

Q:小米盒子wifi是2.4G快还是5G快?
A:5G抗无线信号干扰能力强, 但是信号覆盖和穿墙性能较2.4G弱。如果你的路由器和你的盒子隔得远,中间障碍物多,建议选择2.4G更稳定。毕竟路由器的传输信号质量更影响传输速度

Q:小米盒子怎么打开USB调试模式?
A:盒子系统设置的节能选项里有个安装未知来源选项,选择为允许,在用数据线连接电脑安装软件!

Q:小米盒子自带TF卡卡槽?
A:以前的工程机有卡插槽,正式机只保留了卡插座的位置,要用TF卡,恐怕要焊上个卡插座咯

Q:请问小米盒子在美国能用吗?
A:小米盒子经过众多的米粉测试,可以在美国、欧洲和港澳等地流畅的观看CDN19的片源,请放心使用,其它CDN的片源与CNTV部署有关。

Q:我的小米盒子最近一次升级之后,原本可以正常播放的MKV视频,现在无法正常播放了,只有图像,没有声音,伴随着咋咋咋的杂音。
A:应该是升级带来的问题,尝试降级解决。

Q:共享电脑里的文件用什么好?
A:ES文件管理器,不解释。好吧,还是解释下,ES文件管理器可以连接共享文件夹、FTP文件夹、各种流行的网盘,总之,十分犀利。大家试试吧。

Q:小米盒子的直播速度好卡啊,又丢帧,真烂?
A:很可能网速有问题,或者源没有选择好,遇到丢帧现象,请手动更换源。 经过实测,小米盒子虽然CPU是单核,性能不是非常理想,但直播目前的所谓高清电视节目还是绰绰有余。有本人用小米手机录制的实测视频在群共享作为证据(分别有国内高清卫视、港台直播和成人台的测试)。

Q:家里的电视是用闭路电视信号,貌似没有HMID,但有三个不同颜色的小孔。不知道可不可以用小米盒子
A:可以用,需要买一根“小米盒子AV线”在小米官网盒子配件一栏就有售,用av线链接盒子和电视就可使用了

Q:新的小米盒子支持widi吗?
A:1代都支持 只要你的电脑网卡支持widi输出就行~

Q:小米盒子能接摄像头吗?能上QQ吗?
A:不能接摄像头能上QQ 效果不是很好因为不好操作

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How to survive the digital TV transition
The impending switch to all-digital broadcast TV will be a step forward, but it could be bumpy for many

Over the next year or so, you'll be hearing a lot about the digital TV transition. Here's what you need to know: On Feb. 17, 2009, broadcasters must shut down their analog systems and transmit only digital TV signals to comply with the Digital Television Transition and Public Safety Act.

While that sounds cataclysmic, the change will affect only the way free TV will be broadcast over the air, to a rooftop or indoor antenna. All TVs (no matter what type) connected to cable, satellite, or one of the new telephone company fiber-optic services should continue to function (though you might have to get a set-top box for cable; see below).

A TV connected to an antenna might or might not work after Feb. 17, 2009. That depends on the type of TV.

Which TVs will still work with an over-the-air antenna?

A TV with a built-in digital tuner (called an ATSC tuner) will be able to get free over-the-air digital programming, with no action on your part. Your TV probably has a digital tuner if it falls into one of the following categories:

It's a big-screen, high-definition TV bought within the last few years. The government has required sets with screens 35 inches and larger to have a digital tuner since July 2005, and sets 25 inches and larger since March 2006. Those sets are sometimes called integrated HDTVs.

It's a new TV purchased this year. Since March of this year, all new TVs regardless of size have been required to have a digital tuner. Most TVs bought within the last few months should be OK, whether they're high-definition sets or the new digital standard-definition TVs. (Retailers are allowed to sell off their existing inventory of analog TVs that do not have a digital tuner. They should be clearly marked as analog sets, but ask the salesperson to be sure.)

Which TVs will no longer work with an over-the-air antenna?

A TV that has only an analog tuner, called an NTSC tuner, will not be able to get free over-the-air digital programming. Your TV does not have a digital tuner if it is one of the following:

An older picture-tube TV that is not a high-definition set.

An HD-ready TV purchased several years ago.

A new type of set, called a monitor, that has no built-in tuner of any kind.

(If you're unsure as to whether or not your TV contains a digital tuner, consult the product manual or call the manufacturer's customer service line.)

How can you make those TVs work?

To use any of those TVs to get free TV via antenna, you will have to attach an external device that contains a digital ATSC tuner. (Keep that in mind if, at some point, you disconnect cable or satellite from an older set to use it in your bedroom or basement with an antenna connection.) There are two ways to do this:

You can buy a digital converter box that will accept the digital feed from the antenna and convert it into analog signals your TV can accept. That would enable you to receive digital broadcasts, but they will be converted to lower-quality analog signals—even if your TV is an HD-ready set or an HD monitor. Those converters are starting to show up in stores now, at costs ranging from $40 to $70. Best Buy, Circuit City, Kmart, RadioShack, Sam's Club, Sears, Target, and Wal-Mart are among the retailers that will be offering the boxes and participating in a government coupon program to defray the cost (see below).

You can also buy a new VCR, DVD recorder, or digital hard-disk recorder (sometimes called a DVR) that contains a digital tuner and route signals from the antenna through that device to your TV. A number of such recorders are already available from various brands, many selling in the $200 range. As with TVs, verify with a salesperson that the model you've selected contains an ATSC tuner. You would have to keep the recorder turned on in order to watch TV. An HD-ready set or HD monitor would then be able to display HD, but a standard-definition set would downgrade the signal to analog quality.

Other options for getting TV programming

Alternatively, you could use one of those TVs with cable, satellite, or telephone company video service. Plans start at about $15 to $20 a month for the most basic level of programming, and a digital set-top box typically rents for about $5 to $10 a month.

Satellite and phone company TV are already all-digital, so subscribers won't have to make any changes. TVs connected to those services should continue to function as they do now.

Cable companies must continue to provide service to analog TVs at least through 2012. But if the cable is plugged directly into an analog set, you might have to get a set-top box at some point to continue receiving programming. Contact your cable company to find out if they're planning to switch to all-digital service during that time and whether you'll have to pay for a box.

FEDERAL COUPONS MIGHT HELP U.S. CONSUMERS

Because the federal government is requiring the transition, Uncle Sam will foot part of the bill for the purchase of digital converter boxes. Households with analog TVs connected to an antenna are eligible to receive two $40 coupons to buy two converter boxes (two coupons cannot be combined to purchase one box). Consumers must request the coupons from Jan. 1, 2008 through March 31, 2009. The coupons will expire three months after they're issued. Coupons will be available on a first-come, first-served basis until federal funding is exhausted.

Federal legislation has allocated up to $1.5 billion to this program. Consumers Union, publisher of Consumer Reports, finds little to applaud in this plan, which senior policy analyst Jeannine Kenney describes as "under funded" and "intentionally difficult for consumers to use." "Unless Congress revisits the structure and funding of the coupon program," she said, "the digital transition will be not just an annoyance to consumers, it will be a financial burden as well, undermining the likelihood that the 2009 transition deadline will be met."

For more information on the coupon program, visit the National Telecommunications and Information Administration's web site for the TV converter box coupon program: www.dtv2009.gov. You can phone in questions about DTV to the FCC's toll-free Consumer Center at 888-CALL-FCC (888-225-5322). Other useful online resources: www.dtvtransition.org, a site sponsored by the Digital TV Transition Coalition, a diverse group of TV and consumer electronics industry associations dedicated to educating consumers, and the official Web site of the National Association of Broadcasters' digital television (DTV) transition campaign. You can also check out www.HearUsNow.org, a consumer advocacy Web site managed by Consumers Union for public policy issues such as the transition to digital TV.

ANTENNAS: YOUR LINK TO FREE DTV

The impending transition from analog to digital for local broadcasts has put a whole new spin on over-the-air reception, which lost favor when cable and satellite became widely available. Here's what you need to know about using an antenna to get digital TV broadcasts.

More channels, better quality. Digital over-the-air broadcasts can provide very high-quality picture and sound—including high-definition programming and surround sound—free of charge. You might even get more channels than you did with analog broadcasts, because many networks broadcast several subchannels with different programming than the main station. (You won't pull in cable- and satellite-only stations such as ESPN and CNN.)

What you'll get. The number of stations you can receive digitally, and whether you can receive them, will vary depending on your locale. To find out about digital TV stations in your area, visit http://www.fcc.gov/mb/video/files/dtvonair.html.You'll have the best shot at receiving digital transmissions if there's a clear path to a station's transmitter. Tall buildings, mountains, or trees can block the signal. To gauge the potential strength of the HD signal in your area, check out AntennaWeb.

Antenna choices. Rabbit ears and indoor antennas might work, but a larger roof-mounted antenna is generally more effective at pulling in signals. Larger antennas can also be mounted in attics. You'll find antenna advice at the AntennaWeb. Web site and the HDTV Antenna Labs Web site, an enthusiast site dedicated to reviews of DTV antennas and technical articles.

Installation options. Although professional antenna installation was once a common service, finding an installer today might not be as easy as finding someone to wire a home computer network. None of the major electronics chains our reporter called (BestBuy, Circuit City, and Sears) install outdoor antennas.

AntennasDirect provides a listing of resellers and installers around the country. The do-it-yourselfer can download a useful guide on installing an outdoor TV antenna. You might also find a professional antenna installer in your area on the Homeblue Contractor Network site, or at Craigslist.

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10 things you need to know about Digital TV Antennas

Digital TV antennas have come a long ways since your grandma’s rabbit ears antennas you grew up with. Here is our list of the 10 things you need to know about modern day digital TV antennas.

Broadcast signals are superior to cable and satellite.

There are no paid subscription fees to receive over-the-air (OTA) television, and the picture and sound quality is far superior. In addition, OTA broadcasts are free from the signal compressions used by cable and satellite giving you unadulterated high definition television.

Unlock new local channels.

Cable and Satellite providers do not carry all the channels that may be available in your area. In fact, most broadcast stations offer additional regional programming, absolutely free. These channels include local news, sports, cooking shows, kids programming along with classic TV shows and movies.

All the major networks transmit signals free over-the-air.

You don’t have to pay for some of the content you receive on cable or satellite. The broadcast networks are paid for by advertisers, not subscribers. All your local news, weather, sitcoms, cooking shows, kid’s shows, sports and thousands of movies are available free with an antenna.

‘HD’ or ‘HDTV’ antennas are some of the more common names used for digital TV antennas.

All digital antennas receive the same picture and sound quality; we just give them a familiar name. Some broadcasts will be in full HD while others are broadcast in standard definition. The real difference is the uncompressed signal received with an antenna.

There are channels, and then there are sub-channels.

Each broadcast station sends out a signal on a frequency (channel). This frequency will provide many ‘sub-channels’ containing your programming. For example, a channel broadcast on channel 8, would appear on your TV as sub-channel group 8.1, 8.2, 8.3 etc. Each channel, aside from its main service can be broadcasting additional programming on 1 to 4 sub-channels simultaneously.

Antennas are a great compliment to any cable or satellite subscription.

Complimenting your television setup with a digital antenna will come in handy the next time your cable or satellite blacks out. During emergencies or bad weather, receiving OTA signals to your TV with an antenna will keep you informed. Much like a radio, the frequency is more reliable and less subject to interruption.

Find the broadcast towers before you choose an antenna.

When choosing an antenna, remember that every set up is unique to the location in which you live. Click HERE to learn more about antenna selection.

Hills, trees, and buildings bend, deflect, and weaken signals.

The digital TV signal is a ‘line of sight’ signal. Typically, the higher you have your antenna, the better the reception. While signals pass through walls and other surfaces, the more obstructions the signal encounters, the weaker the signal and this causes signal disruption. The clearest, most unobstructed view to the broadcast towers will allow the antenna to perform at the highest level.

3 things you need to receive over-the-air digital broadcast TV

A television with a digital tuner (found in any TV manufactured after March 2007)
The right antenna for your specific location. See here at Antenna Point
The knowledge of broadcast tower locations in your area. Point your antenna toward them and bask in the glory of OTA, free television.

10. There is no magic antenna.

Antennas come in a variety of shapes and sizes, each designed for a specific situation. Some are narrow focused (directional) antennas; while others are multidirectional both with various range capacities. Well-designed antennas, such as our patented Tapered Loop, are tuned for specific frequency ranges and geographical challenges, which will increase your chances for success.

There is no ‘one-size-fits-all’ solution in an antenna. To help you choose the right antenna, view our Antenna Selection Page or Live Chat with an expert now.

HERE ARE SOME TIPS FOR SUCCESS:

Outdoor installation is best, but Antennas Direct antennas can also be installed indoors or in attics. (50% strength/range is lost indoors).
Simple, direct connections and installations are best. The more junctions in the installation, the higher the signal loss.
Each time the signal is split (to go to another TV) signal strength is reduced, so a low-noise amplifier may be needed to help compensate for the signal reduction.
Install the antenna where signal is “present”. Move the antenna to different locations until signals are found. Many times one end of the roof or room has better signal characteristics than the others.

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FAQ: What does the digital-TV switch actually mean?
It's not too early to think about how to ensure your television won't go dark when analog broadcasts shut down in 2009. Photos: Converting from analog to digital TV

WASHINGTON--If there's one message the government wants you to know about analog televisions going dark in early 2009, it's this: don't panic.

Federal officials say American households will have plenty of time to make sure their gadgets are ready for the congressionally mandated switch to all-digital broadcasts after February 17, 2009.

The key is knowing what your options are. As the U.S. Department of Commerce and the Federal Communications Commission stage back-to-back public events here this week, CNET News.com has compiled a list of questions and answers designed to ward off a DTV D-Day.

Q: Is it true if I subscribe to cable or satellite TV service, I can continue using that hand-me-down TV set from a few decades ago after the switchover?
That's right. Because if you're not even using your TV set's over-the-air tuner, there's no problem. You'll continue to receive all the channels you'd expect--including local broadcast offerings, assuming the service carried them in the first place and will continue to do so--without any need to buy new equipment. And naturally, those who receive Internet Protocol or IPTV--that is, channels shuttled over the Internet--through telephone carriers like AT&T and Verizon, won't have to make any changes either.

Q: I currently rely on free, over-the-air broadcasts and have no intention of ever subscribing to cable or satellite service. What are my options?
If you bought your TV recently, it may already include a digital tuner. As of March 2007, nearly all new televisions should include a built-in digital tuner.

If it's older, you're in the minority that has to do something before the deadline if you want to keep watching over-the-air TV. The simplest--and most expensive--option is to buy a new television equipped with a digital tuner. Many of them are already on the market, labeled as either SDTV (standard-definition television, which refers to an analog TV equipped with a built-in digital tuner), EDTV (enhanced-definition TV, which can display high-definition images but doesn't have enough resolution to do them justice) and HDTV (high-definition TVs, which are the most common type of digital television). (Click here to view CNET's TV buying guide.) You could also choose to purchase a DVD player or recorder equipped with a digital tuner.

The most economical route may be to buy an external digital-to-analog converter box, which is a digital tuner with an analog output that will let older TVs receive digital transmissions after the switch. Beginning January 1, 2008, the federal government plans to allow households to apply for up to two $40 vouchers to defray the cost of designated devices, which manufacturers project will cost $50 to $70 when they hit stores early next year.

Q: Free money from the government?
That's right, although of course you're paying for it yourself (along with the overhead a government bureaucracy to administer the program) in taxes. Regardless of how much money you make or even whether your household relies on free, over-the-air TV broadcasts, you'll be eligible to apply via phone, Web, fax or snail mail for the coupons during a first phase, in which 22.5 million coupons are expected to be available. The last day to make such requests is scheduled to be March 31, 2009. Coupons are set to expire three months after being issued.

If the first wave of coupons runs out, Congress could authorize an additional $450 million, creating up to 11,250,000 more vouchers. But those would be limited to households that claim they rely on over-the-air TV.

The National Telecommunications and Information Administration (NTIA), which is overseeing the coupon program, plans to make more detailed instructions available later this year.

Q: So I can use my address and my friend's address and my mom's address to get a bunch of these coupons, with a market value of $80 for a pair? If I can scare up five mailing addresses somehow, that's $400 for one or two minutes of work, right?
Right.

Q: Dang! Is it legal to resell these vouchers on eBay?
If there's only one person behind five different addresses, it might be considered fraud. We know of no law saying you can't resell the vouchers.

Q: Are they requiring Social Security numbers or something as a check against abuse?
Nope. The Commerce Department chose not to, citing "privacy concerns."

Q: Did Congress really mean to make this so easy to abuse?
Because politicians wanted to respond to concerns from groups like Consumers Union, particularly about low-income and elderly households, they had to offer some kind of subsidy. Anytime the government hands tens of millions of people a new gadget (or a discounted one), short of sending out inspectors to make sure applicants really rely on broadcast TV, there's going to be some form of abuse and waste. Another way to do it might have been an income tax rebate.

Q: I'm an inmate in state prison in Cresson, Penn., and I don't get out for nine more years. Can I and 100 of my best friends here each get $80 in vouchers?
No. Although the Commerce Department mentions the prospect of prisoners (PDF) receiving Digital TV converters on its Web site, a spokesman said the U.S. Census definition of "household" does not include anyone who dwells in prisons and other "institutions," including college dormitories, nursing homes and group homes. That means those TV watchers are not eligible to apply for their own coupons.

Q: Are there any limitations here? Can I use the coupons toward the cost of a digital TV?
The coupons may only be used for converter boxes certified for use by NTIA, and the agency placed a number of restrictions on what features they can employ. For instance, it's acceptable for the boxes to include an electronic program guide feature, equipment necessary for processing software upgrades, antenna inputs and video outputs. They also must meet certain energy efficiency and interference standards.

But the coupons can't be used toward digital TVs themselves or toward more "deluxe" devices that also contain, for instance, DVD-recording or playback capabilities.

Q: Does DTV mean HDTV?
Nope. As federal officials themselves note, digital television comes in many flavors. It can be low-resolution standard definition, or SDTV, or it can be high-resolution, or HDTV, or somewhere in between.

Q: Have any specific models been certified for use with the coupons yet?
Yes. NTIA confirmed that it gave the green light last week to two models produced by a Korea-headquartered company called Digital Stream. In a press release dated Friday, that firm estimated the price for each of those models would be about $70. (A more detailed spec sheet is posted at its Web site.) Several other companies, including LG, Samsung, RCA, Broadcom and Echostar, are reportedly in the process of seeking certification.

NTIA said it plans to include with the coupons it issues a final list of eligible devices, along with retailers near the household's ZIP code that sell some or all of them.

Q: When will the coupon-eligible boxes be available in stores?
The answer to that question remains a little murky. None is on the market yet, but NTIA has said retailers expect to have them by "early next year"--a statement that Best Buy, for one, echoes on its Web site.

Radio Shack vice president of merchandising Larry Harris told attendees at an NTIA public meeting this week that he expects all of the company's approximately 6,000 company-owned and franchise stores to carry coupon-eligible boxes as close to January 1 as they're available. He said the company hopes to begin outfitting its point-of-sale systems to work with the IBM-contracted coupon system within the next 30 days.

Q: What if the coupons run out?
Some consumer groups have argued that Congress should really be making double the number of coupons available to accommodate all of the some 70 million television sets they expect will need the converter boxes. Some Democrats have thrown support behind that idea.

Echoing statements he and other Republicans made earlier this year, Rep. Fred Upton (R-Mich.), the ranking member of a House of Representatives telecommunications panel, said this week that he doubts the coupons will run out. He told NTIA public meeting attendees that about 23 million are expected to be requested, based on the number of consumers who rely on over-the-air television.

If there aren't enough, he added, "I'm sure there will be a bipartisan effort to make sure the funds are there, but I think we'll be OK."

Q: How can I tell whether my TV is currently able to receive digital signals?
Check your owner's manual or the TV set itself for indication that it contains either an integrated HDTV tuner or an Advanced Television Systems Committee (ATSC) tuner, which refers to the American digital-TV standard. If you can't track down the manual in paper form, try searching for your TV's make and model number at the manufacturer's Web site.

A TV designated "HD-ready" or "HDTV monitor," by contrast, does not have a built-in ATSC tuner, which means you must supplement it with a converter box or subscribe to cable or satellite.

The newer your TV is, the greater the chance that it's already primed for the switch. If it's older than a 1998 model, when TV manufacturers first began offering a limited quantity of TVs with integrated digital tuners, it likely needs a converter box. An uptick in the number of TVs equipped with digital tuners began in 2004.

Q: Remind me again--why are we even making this shift?
The U.S. government has actually been attempting to clear off the analog TV spectrum for many years to make the prime airwaves available for public safety responders and for mobile broadband projects. A portion of the vacant spectrum will automatically be set aside for use by emergency broadcasters. The FCC plans in January to start auctioning off the rest to companies, including the likes of Google, eager to take advantage of the spectrum's inherent physical properties, which allow signals to travel farther and penetrate walls.

All told, the auction is expected to generate between $10 billion and $15 billion to offset the government's deficit.

Q: Then who's to say this whole process won't be delayed again?
So far, all we have to go by is the word of Bush administration officials presiding over the plan, and they say they're determined for it to go off without a hitch. "It is critically important for a host of public policy reasons, and that's why it's so important that we get it done," Commerce Department Assistant Secretary John Kneuer told about a hundred people gathered for a digital-television expo (PDF) at the agency's downtown Washington headquarters this week.

Q: What's in this for me as a TV watcher?
Digital television delivers clearer pictures (meaning less-snowy versions of your favorite broadcast TV shows) and sharper sound than its analog counterpart. It also allows broadcasters to do "multicasting" of various channels at the same time--say, weather on one channel, a soap opera on another, and news on a third. According to the National Association of Broadcasters, more than 1,600 television stations already offer digital-broadcasting streams.

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What's the difference between a DVR and a PVR?

Those who are looking to replace their humble VCR or DVD player will most likely have to choose between a Digital Video Recorder (DVR) and a Personal Video Recorder (PVR).
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What's the difference?

They are both essentially the same thing: an electronic device used to record media digitally, as opposed to the VCR’s analogue format. While VCRs use an analogue tape to record and play programs broadcast over television, DVRs or PVRs encode video data in MPEG video formats and store the data in a hard drive.

This is where the main difference comes in. A PVR stores files on a hard drive, and you can keep these for as long as you want. A DVR temporarily stores files on a smaller hard drive, and if you want to keep the files you need to burn them onto an external source such as a DVD. DVRs and PVRs have all of the same functionality of VCRs (recording, playback, fastforwarding, rewinding and pausing) plus the ability to pause 'live' television and resume without missing any part of the program.

personal video recorder - PVR

Short for personal video recorder, PVR is a generic term for a device that is similar to a VCR but records television data in digital format as opposed to the VCR's analog format. VCRs utilize analog tapes to record and play programs broadcast over television, but PVRs encode video data in MPEG-1 or MPEG-2 formats and store the data in a hard drive. PVRs have all of the same functionality of VCRs (recording, playback, fast forwarding, rewinding, pausing) plus the ability to instantly jump to any part of the program without having to rewind or fastforward the data stream.

A PVR is essentially made up of two elements: the device that stores its hardware elements, such as the hard disk drive, power supply and buses, and the software in the form of a subscription service that provides programming information and the ability to encode the data streams.

Two common PVR systems are TiVo and ReplayTV.

PVR vs DVR

The terms PVR and DVR have been floating around for years. But few people really know which is which and what each term is referring to. PVR stands for Personal Video Recorder while DVR stands for Digital Video Recorder. The former emphasize the ability to personalize the device and how it operates while the latter emphasis that it captures into a digital format.

Fortunately, the differences virtually end there as both these terms are simply referring to the same type of device that is used in capturing video from different source; the main source would be cable TV. As previously stated, the term PVR was coined to emphasize the ability to select shows and programs based on your personal preference. Much later, with the advent of HD and digital TV, it became more pressing for manufacturers to indicate that their products are able to work with the newer digital sets as well as accept the new digital format. For this reason, the term DVR came into wide use as a replacement for PVR.

For some time after the initial introduction of the term DVR, there were a lot of products that were either labeled as PVR or DVR. This lead to a moderate amount of confusion on which one is superior and what features can be found on each. This has been aggravated further by the fact that PVRs/DVRs do not often have the same feature set. Their features largely vary from one manufacturer to another and even from one product to the next. This problem has eventually gone away as more manufacturers begin to use DVR to identify their products.

Currently, PVR has largely become obsolete due to the wide adoption of the term DVR. You would probably not see any device that is still labeled as PVR devices. Despite this fact, a lot of users still wish to know the difference between them before going out to buy one for their home systems. It is safe to say that regardless of what you choose, what’s important is the list of features that are included with each device.

Summary:
1. PVR stands for Personal Video Recorder while DVR stands for Digital Video Recorder
2. PVR emphasizes on the personal aspect while DVR emphasizes the digital nature
3. Both are basically referring to the same product
4. PVR has become largely obsolete and is rarely used in favor of DVR

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The Complete PVR Buying Guide

Television is a major part of Western culture. It is a way that people from varying backgrounds are able to truly relate to each other, discussing their favorite shows online or at the water cooler. And while it is not quite possible to eliminate the moments when there is nothing on, television watching has actually become easier and, some may argue, more fun over the last decade. One of the biggest changes to television has been the introduction of digital recording devices, such as Personal Video Recorders, which are also known as PVRs. These devices allow viewers to set recordings for their favorite programs and watch at their convenience without worrying about videocassettes, DVDs or other media. This is because all PVR recordings are stored to an internal hard drive rather than an external piece of media, meaning the PVR can hold hours upon hours of programming. Most consumer electronics stores sell PVRs, but they also come standard with some cable or satellite television packages and are available on eBay.

PVR vs. DVR

One of the things that might cause initial confusion when shopping for a PVR is the difference between a PVR and a DVR, or digital video recorder. In fact, there is no industry standard for how these terms are used. Some brands, such as TiVo, have branded themselves as PVRs because their devices learn the personal preferences of users and then recommend programming, making them more personal. However, other companies simply use the terms interchangeably. Simply put, a PVR is a DVR that is put to personal use, most often in someone’s home. However, that does not mean that a device labeled "DVR" is not appropriate for personal use as well. It is more important to choose a recorder that has the features that meet the priorities of those who will be using it, than it is to choose one that is described with a certain acronym.

Types of PVRs

There are a number of factors to consider when purchasing a PVR for home use. Of course, the PVR must be easy for every user in the house to use. However, it is also important to take into consideration where the PVR will be placed, if it can record more than one program at a time, and if it is compatible with the cable or satellite television system that is already in use in the home. In order to ensure each of these requirements is met, it is a good idea to explore the different types of PVRs that are available.

Set-Top PVR

A set-top PVR is designed to be used in a fixed place with a television set. The most familiar brand name for this type of PVR in the United States is TiVo. Set top PVRs may be included in the cost of a cable subscription or satellite television plan, or may be available from the provider at an extra cost. These PVRs are unique because they also include a receiver for the television signal. This can certainly make setup and maintenance of the PVR easier because there is only one device to consider. Furthermore, some cable and satellite companies provide these types of boxes as an incentive to subscribe to their services, which means they can come at a very low cost or even free to new subscribers. Those who are considering changing or upgrading their television service should certainly ask about any PVR incentives that may be available.

Dual Tuner PVR

One of the early complaints about PVRs and DVRs is that viewers were unable to watch one show while recording another, rendering the device useless if two programs were on at the same time. In order to address these complaints, companies developed dual tuner PVRs. While most PVRs sold today are equipped with dual tuners, not all are. This means those who wish to watch one show while recording another, or who want to record two programs at once will want to make sure the PVR they choose has this functionality. Today, some companies even offer PVR boxes that have up to four tuners, meaning that four different programs on four different channels can all be recorded at once. For a household that has many program scheduling conflicts, a multituner PVR can be a solution.

Portable PVR

Although the most common use of a PVR is to record television programming in one’s home, there are certainly other ways to take advantage of digital recording technology. One way that is not as popular as it once was, is with a portable PVR. What this type of device amounts to is a portable media player with digital recording capabilities, meaning it has an internal hard drive. A portable PVR may also be able to play DVDs, but not necessarily. Today, many people use their laptop computers as portable media players, but a PVR may be a less expensive alternative for those who do not have laptops and still want to watch media while traveling.

PVR Camcorders

Not all portable PVRs are only media players. There are also a number of portable PVRs available that also have built-in cameras. These are not the same as digital camcorders, which still require digital cassettes in order to record video. Rather, these portable PVR cameras record to an internal hard drive. Some of these cameras are quite small and are intended for discreet, unobtrusive recording. A PVR camcorder can be a good solution for short videos that need to be recorded and downloaded quickly without a lot of expensive equipment.

PC-based PVR Software

For those people who do not have the space or do not have compatible television systems for a set top PVR, there are other options available. One popular and affordable way to still enjoy PVR capabilities without a set top box is through a home computer. There is software available that can allow users to turn their personal computer into a PVR system. In order for this software to work properly, the computer that will be used must have a tuner attached to it, so that it can receive television signals in order to record programming. The PC must also have enough available hard drive space onto which it will be recording. This PVR setup is quite similar to that of a set top box, but shows will be played back on the computer rather than on a television set. In cases when a viewer already uses his or her computer to watch television, digital recording software can be an economical and convenient solution.

PVR Capacity

One of the important selling points of any PVR device is the recording capacity of that system. After all, if a PVR does not have the necessary space to record all the programming that the user wants to see, it is not as useful as it could be. This is why it is important to determine how much space is really necessary for a PVR system. The table below should help to clarify how the capacity of a PVR translates to recordable hours.

PVR Hard Drive Capacity Standard Definition Program Hours High Definition Program Hours
160 GB 200 hours 25 hours
500 GB 650 hours 75 hours
2 TB 2200 hours 300 hours

Of course, as the capacity of a PVR increases, so does the price. A household of only one person may not require the same number of hours as a home that has multiple people who will be using the PVR. All of these things should be taken into consideration before making a final PVR purchase.

How to Buy a PVR on eBay

For those people with television service that does not offer PVR services, or who charge a premium for adding a PVR to your subscription, there are more affordable ways to bring the technology into your home. For instance, there are many PVR models, new and used, available on eBay.

In order to find a PVR on eBay, you can simply search for a PVR or DVR using the search box on the eBay homepage. However, if you are unsure what type you want to buy or simply want to see which options are available for you, it can be helpful to browse by category. In order to do this, navigate to the Electronics portal from the homepage. Once there, you can select TV, Video & Home Audio and then navigate to DVRs, Hard Drive Recorders. You will be able to sort by specific brand names as well as price and condition.

As with any electronics purchase, you will want to be sure that the PVR is compatible with your system before completing the purchase. This is easy to do on eBay by reviewing the specifications listed or by asking the seller directly. You may want to ask about the condition of the PVR, or if the purchase includes the necessary cables to connect the PVR to your television. When the seller responds to you directly and does so in a prompt manner and with the information you need, you can feel more secure about your purchase.

Conclusion

Investing in a PVR system can actually improve the experience of watching television in many ways. Not only does it allow for the fast forwarding of mundane commercials, it allows for more freedom in one’s life. With a reliable PVR, even people with favorite, must-see television shows do not need to be subject to network schedules and can watch at their convenience. With set top PVRs it is extremely simple to set up recordings for entire seasons of shows, so that you can be sure to not miss a single episode. But even beyond television, PVR technology can improve media recording and playback in other areas as well. From portable PVR media players to camcorders with internal hard drives, the implications of this affordable and personal technology are far-reaching. Whether buying a PVR through a cable company or finding a great deal on an older model on eBay, there are a variety of ways to bring a PVR system into a home to improve the quality, if not the quantity, of media that everyone in a household consumes on a regular basis.

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DTV Glossary

#

4:3—the aspect ratio of the NTSC TV screen, proportionally four units wide for every three units high, no matter the size of the screen.

16:9—the aspect ratio of widescreen DTV video (including all high- and some standard-definition video), proportionally 16 units wide for every 9 units high, no matter the actual size of the screen.

A

analog—the technology in use for more than 50 years to transmit conventional radio and TV signals. Vinyl recordings and motion picture films are other examples of analog technology.

aspect ratio—the ratio of television picture width to height. In NTSC and PAL video, the present standard is 4:3. In widescreen video, it is typically 16:9.

ATSC—an acronym for Advanced Television Systems Committee, and the name of the DTV system used by broadcasters in the U.S. (akin to European COFDM).

B

bandwidth—the amount of broadcast spectrum available to each communications licensee. For digital transmission, the FCC has allocated 6 MHz (megahertz) of UHF bandwidth for each broadcaster. This amount of bandwidth can carry full-spectrum HD signals, several multicast digital signals, data, or a combination of these elements.

barn doors—a term used in television production to describe the effect that occurs when a 4:3 image is viewed on a 16:9 screen. Viewers see black bars (“barn doors”) on the sides of the screen. Also called pillar-boxing.

binary—a numbering system using only the digits 0 and 1. All computer programs are executed in binary form.

bit—a binary digit—the smallest unit of data in a digital system. A bit is a single 1 or 0. A group of bits, such as 8-bits or 16-bits, compose a byte.

byte—a group of bits. The number of bits in a byte depends on the processing system being used. Typical byte sizes are 8, 16, and 32.

C

COFDM: (acronym for “Coded Orthogonal Frequency Division Mulitiplexing”)’the DTV standard used in Europe (akin to ATSC in the U.S.).

compression—the process of fitting a large file into a space that is many times smaller. In the case of video, the method used for the DTV standard is MPEG-2.

computer input—Some HDTV sets have an input (typically SVGA or VGA) that allows the TV set to be connected to a computer.

D

datacasting—Digital television allows for the transmission of not only digital sound and images, but also digital data (text, graphics, maps, services, etc.). See our KET DataCast page for more information.

DBS—See direct broadcast via satellite.

digital cable—a service provided by many cable operators which offers viewers more channels, access to pay-per-view programs, online guides, and in some cases HDTV.

digital television (DTV)—a more efficient and flexible form of television broadcast technology. Since television came into being, stations have broadcast programs using an analog signal, where subtle changes in the waveform define the image and sound. With digital television, the signal is broadcast as “bits and bytes,” the same as computers use. That means DTV can deliver high-definition pictures, surround-sound audio, and several channels all at the same time.

digital tuner or digital receiver—A digital tuner serves as the decoder required to receive and display digital broadcasts. A digital tuner can downconvert broadcasts for an analog TV or provide a digital signal to a digital television. It can be included inside a TV set or via a digital TV converter box.

digital TV converter box—a set-top device that connects to a traditional analog television set and enables it to receive digital broadcast signals via an antenna.

digital video recorder (DVR)—a video recording device (such as TiVo) that uses a hard disk drive to record programs.

direct broadcast via satellite (DBS)—a form of television delivery in which subscribers receive programs via a small satellite dish. The signal is NTSC, digitized and compressed via a proprietary format and decompressed by a set-top box. Some DBS services offer DTV and HDTV content.

Dolby Digital—the approved 5.1-channel (surround-sound) audio standard for ATSC digital television. Six distinct audio channels are used: left, center, right, left rear, right rear (indicated by the “5”), and a subwoofer (indicated by the “.1”).

Dolby Surround (Dolby Stereo)—four audio channels (left, center, right, and surround) converted to two channels referred to as right-total and left-total.

downconverting—the process by which a high-definition signal is converted to a standard-definition picture.

DTV—See digital television.

E

electronic programming guide (EPG)—an application that provides an on-screen listing of all programming and content that a DTV viewer has available. Also called interactive programming guide (IPG).

F

FCC—the Federal Communications Commission; the body that governs, among other things, radio and television broadcasting in the U.S.

H

high-definition television (HDTV)—a digital television format that provides high-quality widescreen pictures with Dolby 5.1 surround sound. The aspect ratio of HDTV pictures is 16:9. This is the most superior video picture available in digital TV. In the U.S., the 1080i (see interlaced scanning) and 720p (see progressive scanning) formats are the two acceptable HDTV broadcast formats. HDTV is a type of DTV.

I

interactive programming guide (IPG)—an application that provides an on-screen listing of all programming and content that a DTV viewer has available. Also called electronic programming guide (EPG).

interlaced scanning—Interlaced scanning sends information to each pixel in the even-numbered rows of pixels in a frame of video, then to odd-numbered rows. 1080i is an interlaced-scanning standard. (See also progressive scanning.)

I/O—“input/output”; typically refers to sending data to and from devices.

L

letterbox—refers to the image of a widescreen picture on a standard 4:3 aspect ratio television screen, typically with black bars above and below. It is used to maintain the aspect ratio of the original source of 16:9 aspect ratio video.

M

MPEG-2—compression standards for moving images and audio set by the Motion Pictures Expert Group (MPEG), an international committee of industry experts. MPEG-2 is the basis for ATSC digital television transmissions in the U.S.

multicasting—the ability to send more than one channel of programming within the allotted channel spectrum. While analog channels have traditionally used a standard amount of spectrum (represented by each click on your tuner dial), digital channels can squeeze four or more channels into their spectrum.

N

NTSC—National Television Systems Committee; the group that set the analog television standard 50 years ago. The abbreviation NTSC is also used to refer to the analog television standard in the United States.

P

PAL—Phase Alternation Line (PAL) is the analog television display standard that is used in Europe and certain other parts of the world. The U.S. uses the NTSC standard.

Pillar-boxing—a term used in television production to describe the effect that occurs when a 4:3 image is viewed on a 16:9 screen. Viewers see black bars (“barn doors”) on the sides of the screen.

pixel—a combination of the words “picture” and “element.” A pixel is the smallest discernible sample of video information, the “little dots” that make up an overall picture.

pixels per inch (PPI)—the measure of the sharpness (that is, the density of illuminated points) on a television display screen.

progressive scanning—Progressive scanning sends information to each pixel in a frame of video sequentially—left to right, top to bottom—to create the image. 720p is a progressive-scanning standard. (See also interlaced scanning.)

R

resolution—the amount of data used to make up a picture, screen, or audio track. The more data in a picture, the richer the image and the higher the resolution. Resolution is measured in a number of ways, depending on the medium used. For example, digital TVs describe their resolutions in terms of the number of pixels or dots that make up the picture along the vertical and horizontal axes. 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 more than 2 million (1080 X 1920 = 2,073,600) color pixels creating the image. By way of contrast, old analog televisions have about 480 active lines, with each line holding about 440 pixels. So each frame has slightly more than 200,000 color pixels in use creating the image.

S

standard-definition TV (SDTV)—a digital television format similar in quality to NTSC. While not as high-quality as HDTV, SDTV signals display clear pictures and sound without noise, ghosts, or interference.

SVGA—acronym for the Super Video Graphics Array display mode. SVGA computer monitors have a resolution of at least 800 X 600 pixels.

T

terrestrial broadcasting—a broadcast signal transmitted “over the air” from a ground-based transmitter to an antenna.

U

upconverting—the process by which a standard-definition picture is changed to a simulated high-definition picture.

V

VGA—acronym for the Video Graphics Array display mode. VGA computer monitors have a resolution of at least 640 X 480 pixels.

W

widescreen—a term given to picture displays with a wider aspect ratio than NTSC 4:3. Digital HDTV or SDTV is referred to as “16:9 widescreen.” Most motion pictures also have a 16:9 widescreen aspect ratio. Most digital TVs have screens wider than they are tall (for every 9 vertical inches, a DTV screen is 16 inches wide).

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