What kinds of channels are there?

Channel: Television broadcasters receive their frequency assignment from the FCC. To make it easier for home users, the frequency bands were given "channel" numbers. For example, WCBS-TV broadcasts in the 54-60 Mhz band, which is designated as Channel 2.

Digital Channel: Under the new digital television scheme, most broadcasters are being moved to new frequency bands with new channel numbers. For example, WCBS is already broadcasting in digital as WCBS-DT. Their digital channel is 56, which is the same frequency band as UHF channel 56: 722-728 Mhz. Antennaweb.com calls the digital channel a "frequency assignment"; avsforum.com calls it the "actual channel."

Digital Virtual Channel: Many broadcasters have spent decades promoting their channel numbers to the public and needed  a way to maintain their old brand identity in spite of the new assignments. Also, because of the compression and multiplexing available with digital, broadcasters can now transmit multiple program services within their assigned frequency. To accommodate both legacy branding and multiple simultaneous feeds, a system of digital virtual channel numbers has been established. It consists of a number and a decimal. For example, WCBS-DT's main programming service is called Channel 2.1. The "2" represents the old VHF channel number they have used for over 60 years, and the "1" designates the first subchannel. If WCBS were to add Spanish-language programming, they might designate it Channel 2.2. Note that there is no standardized name for the digital virtual channel. On Wikipedia, it's called a "digital channel"; on antennaweb.com, it's called a "channel"; on avsforum.com, it's called a "virtual remapped channel."

QAM Channel: Cable systems distribute their programming using a technique called QAM. QAM channel numbers are chosen by your cable company and have nothing to do with the FCC-assigned channel numbers. If you don't have a set-top box, you select your programming using the QAM channel numbers above. If you do have a set-top box, ignore QAM and use your cable operator's program guide.

What is PSIP (Program and System Information Protocol)?

Over-the-air broadcasters transmit PSIP data to tell digital TVs which digital virtual channel corresponds to which digital channel.

What channels do I get on cable?

Assuming you have no cable box and Time Warner's Basic Cable service, you'll be able to view the unscrambled channels. Those are your local broadcast stations plus whatever other programming services Time Warner chooses to provide. You may also be able to view some of the local stations in high definition. 

Terminology: Unscrambled cable channels are called "clear QAM." Local broadcast stations that the cable companies are required to carry are called the "must-carry" stations.

How do I enter a channel number?

It depends on your television receiver, but you can probably drop leading zeroes. Also, sometimes a period may be used in place of the hyphen.

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References:

For a list of broadcast bands (frequency assignments) and their corresponding channels, see http://www.csgnetwork.com/tvfreqtable.html or http://en.wikipedia.org/wiki/North_American_broadcast_television_frequencies

Over-the-Air Digital Television Reception FAQ: http://www.avsforum.com/avs-vb/showthread.php?p=6652075&&#post6652075

Clear QAM: https://answers.launchpad.net/me-tv/+question/30257

Find your local OTA stations: http://www.antennaweb.org/aw/welcome.aspx

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This site is maintained by Nostradamus Advertising, a division of Advocate Enterprises, Inc. It is entirely unofficial. If you find an error or have a suggestion, please drop us a note. For official Time Warner Cable information, please go to their site. Last updated 01/08/2009 10:26:26 AM .