Digital TV

• The FCC reports the U.S. Congress required all over-the-air, or terrestrial, television broadcast stations to stop transmitting analog television signals in 2009. These broadcasts were replaced by all digital broadcast signals to allow more of the available broadcast spectrum for emergency communications and improve picture and sound quality for TV viewers.
  
  

Receivers

• The FCC explains the term "digital receiver" is also known as a digital tuner, which decodes the digital signals sent by the free over-the-air broadcaster and allows them to be displayed on a television. A majority of television sets manufactured after 2007 have built-in digital receivers and antennas, allowing free over-the-air broadcasts to be viewed.
  
  

Analog

• The DTV website explains digital receivers for terrestrial broadcast TV can take the form of converter boxes to transform digital broadcast signals into analog signals to be viewed on older television sets. A set top digital receiver requires the use of an indoor or rooftop UHF/VHF antenna to receive terrestrial digital broadcast signals.