Step 1: What is happening to television?

Snapshot:

• Local TV stations broadcast their TV channels OVER-THE-AIR for free viewing.  Many viewers receive the channels with an ANTENNA.

• The TV broadcasting system in the U.S. is called ANALOG TV.  Now TV stations are changing to a new, DIGITAL broadcasting system.

• DIGITAL TV is here now!  Nearly all "full power" TV stations have turned on a new DIGITAL TV channel while their old ANALOG channel is still on the air.

• The DIGITAL TV system is fantastic!  It features clear, crisp pictures and sound, wider programs, and High Definition TV for viewers who have HDTV sets and an HD signal source.  And the channels are still free.
  

• By law, U.S. TV stations must shut off their old ANALOG channel by February 17, 2009.
  

• Older, ANALOG TV sets cannot tune in the new DIGITAL TV channels using just an antenna.  Older TVs would just receive noise.
  

• Viewers who watch TV with an ANTENNA must take some steps so they can watch the new DIGITAL TV channels.

• Owners of older TVs have several choices for how they can watch the new DIGITAL TV channels.  No TVs will become obsolete or stop working.

• CABLE TV and SATELLITE TV are not affected by the change to DIGITAL TV.  Their subscribers probably don't have to do anything.

• Read steps 1 - 4 for more information.

The way that television station signals are broadcast from TV towers to your home is changing.  Here's why.

Television stations in the United States have used an ANALOG system of sending their signals over the air since commercial broadcasting began in the 1940s. 

With the ANALOG system, TV pictures are sent from a TV transmitter to a TV receiver using radio waves.  At the transmitter, a TV picture controls the strength of the radio waves.  Bright pictures make stronger waves, and dark pictures makes weaker waves.  So the radio waves change from weak to strong and back, very quickly, depending on the TV picture.  A traditional ANALOG TV set receives the radio waves with an ANTENNA and converts them back to a picture on the TV screen. 

This ANALOG TV system has worked well, but it is nearly seventy years old!  Now TV engineers have developed a new, DIGITAL TV broadcasting system.  The digital system works by turning a TV picture into a digital file, like music or video files on a computer. 

The DIGITAL TV system still uses radio waves to broadcast the TV signal.  But now the radio waves from the TV transmitter are sending a digital file of the TV picture.  A TV with a DIGITAL TUNER receives the radio signal.  It has a computer to read the digital file and convert it back into a TV picture and sound.  Viewers can watch the DIGITAL TV signal for free.

The new DIGITAL TV broadcasting system has many advantages, including:

• Crystal clear TV transmission.  DIGITAL TVs receive an identical copy of the TV picture that was transmitted, so they can show clear, sharp TV pictures.
  

• Wider TV picture.  With the DIGITAL TV system, TV pictures can be one-third wider than traditional TV pictures.  DIGITAL TVs have wider screens to show all of the wider digital TV pictures.
  

• Clear, crisp sound.  DIGITAL TV includes digital-quality stereo sound (with left and right channels), and for some programs, it includes 5.1 CHANNEL SURROUND SOUND.
  

• HIGH DEFINITION TV (HDTV).  DIGITAL TV includes the ability to transmit programs in HIGH DEFINITION (HDTV), a high quality TV format with pictures that have up to five times more detail than traditional ANALOG TV.  (Viewers must have an HDTV and an HDTV signal source to see true HDTV pictures.)
  

• Several TV programs can be broadcast in one TV signal (from one TV transmitter).  This is called "multicasting."  Inside the same space as one traditional ANALOG TV signal, DIGITAL TV can transmit several programs at the same time, including channels for future services like TV for cellphones and cars. 
  

Plus, just like ANALOG TV signals, the DIGITAL TV signals from community TV stations are still local, portable, and free.

Most U.S. TV stations have already begun broadcasting a new, separate digital channel while they continue to broadcast their traditional ANALOG channel. To continue the transition to DIGITAL TV, the U.S. Congress chose February 17, 2009, as the date when all U.S. FULL POWER TV stations must turn off their ANALOG channel.  After that date, U.S. FULL POWER TV station broadcasting will be ALL DIGITAL. 

Older, ANALOG TV sets cannot tune in the new DIGITAL TV channels using just an antenna.  Older TVs would just receive noise.  So viewers who watch TV with an antenna must take some steps so they can watch the new DIGITAL TV channels.  See Step 2 for ways to watch DIGITAL TV. 

And just because the ANALOG TV channels are shut off does not mean that older TVs will be obsolete or will stop working.  There are several ways to use older ANALOG TVs to watch the new DIGITAL channels!

There are some TV stations that are not affected by the change to DIGITAL TV yet.  These are TV stations that are licensed for LOW POWER.  They include LOW POWER TV ("LPTV") stations, "Class A" stations, and TV TRANSLATORS, which are transmitters that rebroadcast the signals of distant TV stations to rural or mountainous communities.  This group of stations has not been given new digital channels and is not required to change to digital broadcasting, so these stations will continue to broadcast in ANALOG.  There is more information on continuing to watch ANALOG channels in the section "How To Watch Digital TV." 

This year, all TV viewers need to think about how the change to DIGITAL TV may affect them.  Most viewers won't be affected at all.  Others will need to take action to make sure they can continue to watch their local TV stations when their channels become ALL DIGITAL. 

Read and watch Step 2 to find out how DIGITAL TV affects you.  
 
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CAPITALIZED WORDS are defined in the Digital TV Glossary of Terms.