Digital Television

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Introduction

Important.png Note: This page applies to United States users only. Official information on the change is found here

Starting February 17th, 2009, through June 12th, the United States will change from analog broadcast television to digital broadcast television. This change has some implications for MythTV users and this page will try to answer some of the most common questions and misconceptions. This table generalizes the situation

Type of service Need to change
Analog antenna/broadcast
Yes
Cable television
Maybe
Satellite television
No

Because the cutover has been changed by Congress from a single date to a time period, different stations may change to digital on different dates, and because the digital switch over may involve channel changes you may be forced to update your lineups quite a number of times during the period, depending on where you live. How well scheduling providers will keep up with this is unknown.

Digital vs. HDTV

One common point of confusion is the use of digital television and HD television interchangeably. Digital television is simply the digital broadcast of TV signals compared to analog broadcast. Digital does not require a signal to be HD. HD is defined by the resolution of the content. Digital broadcasts can be in both SD (standard definition) and HD (high definition) formats.

Analog antenna/broadcast users

If you currently receive television using a standard antenna, you need to change equipment to continue to receive digital broadcasts. You have two basic options without changing to another type of service: a digital converter, or a digital broadcast capture card.

Digital converters

These are set top boxes which convert the digital broadcast signal back to analog so your existing equipment does not have to change. They tend to cost about $40-50, are of varying quality, and you can get a coupon for up to 2 of them from the government -- though both the coupons and the boxes may be in short supply at this late date. These should work fine with MythTV, but might require use of an IR blaster to change channels and will also require one converter per tuner in your system.

Lirc Config Files for Converter Boxes

Important.png Note: If you have a working config file for a digital converter box please attach it here for reference.

Working Config for the RCA DTA800b:

begin remote

 name  RCA_DTA800b
 bits           24
 flags SPACE_ENC
 eps            30
 aeps          250
 header       3750  4206
 one           252  2240
 zero          252  1245
 ptrail        275
 gap    8292
 toggle_bit_mask 0x0
     begin codes
         1                        0x7318CE
         2                        0x7328CD
         3                        0x7338CC
         4                        0x7348CB
         5                        0x7358CA
         6                        0x7368C9
         7                        0x7378C8
         8                        0x7388C7
         9                        0x7398C6
         0                        0x7308CF
         -                        0x76189E
         menu                     0x7088F7
         info                     0x73C8C3
         ok                       0x7F480B
         up                       0x7598A6
         down                     0x7588A7
         left                     0x7568A9
         right                    0x7578A8
         ch+                      0x72D8D2
         ch-                      0x72C8D3
     end codes

end remote

Digital broadcast cards

These cards are commonly sold as HDTV capture cards. They will have various features such as ATSC support, QAM support, or 8VSB support. They may also advertise if they support OTA signals. For digital broadcast capture, OTA support is required. This is synonymous with 8VSB and should be what you look for when purchasing a card. This tuner is analogous to a typical analog capture card like a PVR-150 and would take the place of that card in a digital setup.

A good example of this card in a PCI format is the AverMedia A180. There are other cards available, but you must choose one which is compatible with Linux and hence Myth.

The digital converter coupons cannot be used for computer capture cards.

Changing to digital capture will require changes to your lineup/video sources. This page may provide some guidance on how to proceed in scanning for digital channels and configuring the mapping of them to programming guides.

Cable TV users

Important.png Note: There is no requirement from the government for changes to cable television in conjunction with the change to broadcast TV

That being said, many cable companies are taking advantage of the change to force users to change to digital services and require the use of a STB, set top box, in order to receive programming.

If your cable provider requires the use of a STB to receive all stations, then this change will affect your MythTV configuration. You should refer to the Recording Digital Cable page for additional information. Effectively, you will require one STB per tuner.

Satellite TV users

Important.png Note: There is no change required by the government for satellite TV delivery.

Individual States

As mentioned in the introduction, different areas of the country are now allowed to change at different times (between Feb 17 and June 12, 2009). As a result there is confusion about when you need to change in your area. Below is a list of states and/or areas and the dates that the changes are to take place.

Utah Feb 17, 2009 according to the Utah Broadcasters Association.