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Charter TV in HD Reference Information

When connected to an HDTV, Charter TV in High Definition (HD) provides a picture that is 5 times sharper with color resolution that is far superior to regular television.

Digital signals and advanced television combine to create a picture quality clearer than that of analog signals.

Click here for HDTV Troubleshooting information.

General Information

High-Definition Television (HDTV) is a type of Digital Television (DTV) that receives and/or displays high-definition images and typically Dolby® Digital 5.1 Channel surround sound.

HDTV programming and HDTVs together provide an image that is five-times sharper than a standard TV due to the increased number of pixels contained in the received signal.

HDTV screens are wider than the traditional analog TV screens. Analog TVs offer a screen aspect ratio of 4:3 while HDTVs offer an aspect ratio of 16:9, which is similar to a movie screen. This allows you to see movies as they were filmed without reformatting. There are also HDTV-capable sets that have the regular TV 4:3 ratio but format HD content in a letterbox presentation (with black bars on the top and bottom of the TV image).

Enhanced–Definition Televisions (EDTV) also exist. These 4:3 aspect ratio TVs cannot receive HD-formatted signals. They can receive enhanced-definition signals, which do not have the detail of an HD signal but do improve on the Standard-Definition (SD) picture.

Equipment Needed

Your high definition experience isn’t complete without these three essential components:

  • A high definition television
  • A Charter HD receiver
  • HD programming available with Charter Digital Cable®

HD Programming Available

Click here to view our current lineup of HD programming. You will need to provide your address to view the availability of HD programming in your area. The "Available In" column will indicate if the channel is available in Standard Definition (SD) or High Definition (HD).

channel lineup

With Charter TV in HD, you can subscribe to a number of HD channels. Programming line up may vary by location. Available channels may include the following:

  • Local affiliates for ABC, CBS, NBC, Fox, PBS, CW
  • Independent, local HD broadcasters
  • Discovery HD Theater
  • HBO® HDTV, Showtime® HD, Cinemax HD (you must subscribe to each of these premium services)
  • HDNet and HDNet Movies
  • Starz®
  • TNT™
  • Universal HD
  • MHD
  • Wealth TV
  • PPV events in HD

Note: Channel availability varies by location.

HD Programming On Analog TV

You cannot receive High Definition Programming and display it in HD on an Analog TV set.  You need to have a high-definition television with an HD receiver to display HD programming.


Some of the latest models of HDTV sets have a slot for cable cards, which are an alternative to Charter's digital set-top box. If you own a CableCARD HDTV†, you have the option of leasing a CableCARD from Charter to receive encrypted HD programming.

Charter's CableCARD »

CableCARDs will not provide access to digitally encrypted switched channels in areas where Charter has implemented Switched Digital Video (SDV). In SDV areas, HDTV CableCARD customers will need an HD Receiver to view digitally encrypted switched channels. Customers using a CableCARD TiVO device, retail MOXI device or certain supporting CableCARD devices with a Windows Media Center PC will need to install a Tuning Adapter to view digitally encrypted channels.

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TV Type

Cathode Ray Tube (CRT)

Traditional TV technology

  • Available in both standard definition and high definition
  • Quality picture and viewing angles at a low cost, long lifespan
  • Size and weight, image size is limited
  • Generally no longer available in stores

Liquid Crystal Display (LCD) Rear Projection

Similar to front projection technology, but the projector is inside the TV and the image is generated from the rear

  • Larger picture sizes
  • Not flat
  • Generally no longer available in stores

Liquid Crystal Display on Silicon (LCoS) Rear Projection

Improved LCD technology

  • Higher resolution and higher contrast images than standard
  • Not produced by all companies due to difficulty mastering the technology.  May produce a visible "rainbow effect"
  • Generally no longer available in stores


Liquid Crystal Display (LCD) TV uses flourescent backlighting

  • Pros: Larger varety of sized, greater availability, thin design
  • Cons: Trouble displaying images in motion


Flat panel TV that uses an electrical charge to turn noble gasses into image-displaying plasma

  • Pros: Quality black level and colors, contrast, available in large sizes
  • Cons: Burn-in, heat generation, uses more electricity and is heavier than LCDs
    • Newer innovations have reduced the impact of these issues.

LCD w/LED Backlight

An LCD TV that uses LED backlighting rather than fluorescent lights used in traditional LCD TVs

  • Pros: Greater contrast, quality black level, thinner design
  • Cons: Trouble displaying images in motion

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HDTV Glossary

Aspect Ratio

The aspect ratio of a TV image is the ratio of the picture’s width to its height.   Two aspect ratios are used for all television images:

  • 4:3 For every 4 units of measurement of width the image is 3 units high.  (Measurement units could be pixels, inches, centimeters, or some other format.)
  • 16:9 For every 16 units of width, the image is 9 units high.  16:9 is also called the wide-screen format.

TV sets and TV programming have separate aspect ratios.
A 4:3 set can display either 4:3 or 16:9 programming usually with the aid of a Digital Receiver.

  • 4:3 programming fills the entire   screen area.
  • 16:9 programming will either be cropped so the image can fill the screen (losing part of the image on the sides), or will be displayed in letterbox format with black bars above and below the image.

A 16:9 set can also display either 4:3 or 16:9 programming.

  • 4:3 programming may be stretched to fill the screen (distorting the image) or be displayed with black bars on each side of the image to maintain the proper image ratio.
  • 16:9 programming fills the entire screen area to provide a viewing experience similar to that of a movie theater screen.

Data Rate

The data rate is the number of bits per second (bps) used to transmit a digital video and audio stream.


DVI stands for digital visual interface. DVI is an all-digital link between a video/audio source
such as an HDTV set-top and a display device such as an HDTV. The DVI link provides an
uncompressed digital stream at rates up to 5 Gbps between the two devices. The DVI link
does not contain audio, and as such, audio still needs to be connected from the set-top to the
HDTV or home theatre system. One advantage of DVI is that the link allows graphics to be
Sent along the link as well. This allows the user interface from the set-top to be displayed on
the HDTV.

EIA-608 Closed Captioning

EIA-608 (native 608) closed captions are Captions formatted and presented in the
current analog television system and carried on the two fields of line 21 of the vertical
blanking interval.

The common look and feel of native 608 captions is limited to white block
letters within a box-like black background field. Color (non-white) characters, while possible, are only occasionally used due to the 13-year legacy of set-top decoders, which cannot display colored captions. (Note: definition courtesy of ATSC).


HDCP stands for High-Bandwidth Digital Content Protection.  HDCP is the copy protection standard that is associated with DVI and HDMI. 

Any Display device connected via a DVI or HMDI to a Digital Receiver must support HDCP, otherwise no video will be displayed


HDMI has generally replaced DVI as the most common digital connection for consumer electronics.  HDMI is based on the DVI specification but adds audio support in a smaller form factor.  A DVI port can be connected to a HDMI port using an adaptor, but audio would need to be connected separately. 


Home Theater System

A home theater is the set of equipment that gives you the best in-home reproduction of a
theater experience. A typical home theater system would contain most of these

  • HDTV - As discussed previously in this document, HDTV brings the TV viewing experience to an incredible new level.                                                
  • Digital Receiver - Receives the HDTV signal from the cable system.
  • DVD Player - The most common piece of additional equipment in a home theater system, the DVD player lets customers view their own DVD movies.
  • Audio/Video (A/V) Receiver - Have both audio and video connections for most equipment, allowing customers to control many functions of the home theater from one place.
  • Surround Sound - A great sound system with quality speakers placed properly is crucial for home theater.  HDTV takes surround to a whole new level.  Dolby 5.1 has been chosen as the standard for Digital Cable.

IEEE 1394

IEEE 1394 is a high-speed data interface to connect consumer peripherals to devices such as personal computer, digital receiver, digital VCR or DVD recorder.  The interface is also sometimes referred to as a firewire interface or i.link interface.

Overlay graphics, such as the Interactive Program Guide, are not displayed over the IEEE 1394 interface. Connected devices must support DTCP 5C, otherwise no video will be displayed.  If a program is transmitted as Copy Never, recording devices will not record any video (aka a black screen)


The Motion Picture Experts Group (MPEG) is the standards body that developed the video and audio compression standards used in today’s digital television transmissions. Compression is used to minimize the data stream to preserve transmission bandwidth.

MPEG has several different standards for video compression.

  • MPEG1 was the original compression standard meant for use in computers and for audio signals.
  • MPEG4 is a newer standard that has limited usage so far.

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Picture Effect: Centercut

A method of broadcasting 16:9 content to fit in a 4:3 space wherein the left and right edges are cut and only the center of the video is displayed.  The screen is filled, but some of the video cannot be seen.

Picture Effect: Letterbox

A method of broadcasting 16:9 content to fit in a 4:3 space wherein the black bars are added to the top and bottom of the video.  All of the video can be seen, but the screen is not filled.

Picture Effect: Postage Stamp

The 'Postage Stamp' is a reference to having black bars on all four sides of the video.  A number of factors add up to cause this effect.   An example is the down-conversion of an HD broadcast in letterbox to be re-transmitted for reception on an SD channel but viewed on an HDTV.


  • Pixels are small red, green, and blue dots that make up a picture on a TV screen.
  • Pixels are evenly distributed across the screen.
  • By combining these colored dots in different patterns and intensity, the TV can produce the entire color spectrum.

QAM Modulation

  • QAM stands for Quadrature Amplitude Modulation.  In digital cable, it is a modulation technique used to transmit data over the cable network.  In digital cable, 64 QAM and 256 QAM are employed to modulate the data.  64 QAM allows a maximum data payload of around 27 Mbps.  256 QAM allows a maximum data payload of around 38 Mbps.
  • A 6 MHz cable channel is capable of transmitting a single analog channel.  Assuming standard-definition digital channels are an average of 3.5 Mbps, you can transmit anywhere from 7 to 10 channels in that 6 MHz cable channel. 
  • With high-definition channels being a maximum of 19.25 Mbps, you can transmit up to two high-definition channels in the 6 MHz channel using 256 QAM modulation.


Resolution is a measure of picture detail. Resolution is described by the number of horizontal pixels by the number of vertical pixels (lines).  For example, 1280x720 or 1920x1080.  Usually the number of lines are paired with the refresh method to refer to the type of video being displayed (i.e. 720p or 1080i).


RGB is the component format in which the Primary colors (red, green, and blue) are  
transmitted as three independent components. Some older HDTV monitors have only RGB
inputs. Monitors with RGB inputs also require separate horizontal and vertical sync inputs.

Screen Refreshes  

The video displayed on a TV screen is a trick of the eye using quickly refreshed pictures that give the illusion of motion.  Many newer HDTVs have a screen refresh rate that is greater than the actual video frame refresh rate.  This is done to improve the image due to the characteristics of the display technology being used.  Screen refreshes can be performed in one of 2 ways:

Interlacing - Interlaced (i) means that every other line is updated with each refresh.  It takes two passes to completely refresh the screen

Progressive - Progressive (p) means that every line is updated, in sequential order, with each refresh.

So 1080i video may look better for a movie due to the additional lines, while 720p video can result in a better picture in high action scenes, such as sports.  1080p would combine the best parts of both options, but at the cost of twice the data rate.  Equipment support and program availability for 1080p is still limited.

  • 4K enabled televisions offer the highest quality HD experience, especially on televisions 40-inches or larger; however, if your television is smaller than 40-inches the visual differences between 4K, 1080p, 1080i, and 720p resolutions are minimal.
  • Since the vast majority of programming is currently produced in 720p and 1080i, if your television is enabled with 1080p or 4K technology, your TV will convert our HD signal so you can continue to enjoy Charter TV.



Short for Sony/Philips Digital Interface a digital audio interface format developed jointly by the Sony and Phillips corporations, SPDIF allows the transfer of digital audio signals from one device to another without having to be converted first to an
analog format.

Maintaining the viability of a digital signal prevents the quality of the signal
from degrading when it is converted to analog.

SPDIF Optical - uses a fiber optic cable to provide connectivity for audio signals to a home theater system.

DigitalSub Channels

Local broadcasters may use their FCC assigned over-the-air digital channel to provide one or more sub-channels beyond their primary channel.  When using a Charter digital receiver or CableCARD enabled device to access any of these channels carried by Charter, simply tune the Charter assigned channel number.  When using a clear QAM tuner in a TV or other device, you would tune the actual physical channel and program number.   Typically to do this, enter the physical channel, a decimal or hyphen, and the program number (e. g. 3.1, 14.2).  This will vary by market, but a channel scan by the TV or other device will determine which ones are available.


YPbPr is the component video format in which the luminance (Y) is represented separately from the color components (Pb and Pr). The majority of HDTV’s today support this format. The Y output on HDTV’s and HDTV receivers is provided as a Green jack, the Pb is provided as a Blue jack and the Pr is provided as a Red jack. The colors themselves are not to be confused with an RGB output.

DTCP 5C Copy Protection

5C copy protection is the copy protection standard that is tied to the IEEE 1394 interface. Content that is encoded with the 5C copy protection standard, may be labeled Copy Freely, Copy Once, or Copy Never.  When content either enters or exits the set top via the IEEE 1394 ports, and it contains 5C copy protection, then the set top must adhere to the applicable 5C rules, such as turning on Macrovision for the NTSC outputs if the content is labeled as Copy Never.


8-VSB stands for 8-level vestigial sideband.  It is a modulation technique chosen by the ATSC for the transmission of DTV broadcast signals (aka off-air).

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