When we speak of transmission of pure digital television, we mainly talk about its reception and display of the signals. These signals come to us through the broadcasting over air or by transmission through the satellite system or cable system in our houses. There is a class of Direct TV that is getting a lot of name at present which is called DirecTV HDTV. When we combine a digital TV of high resolution with a Dolby surround sound (AC-3), we get a DirecTV HDTV. To have a stunning image, this combination has been made.
A new production and transmission equipment at the DirecTV HDTV station and even a new equipment for reception for DirecTV HDTV is required by the consumer. The strongest selling point for DirecTV HDTV is the higher resolution picture. After media’s perfect show up about DirecTV HDTV, the DirecTV HDTV has reached to all the electronic stores. The higher resolution which produces crystal clarity, as never seen before through picture tube, gives us a life like picture and digital sound. A usual TV gives us an effective picture resolution of about 210,000 pixels whereas in the highest resolution DirecTV HDTV format, each picture contains 2 million pixels. This nearly gives us ten times more detailed picture. The basic aim behind DirecTV HDTV is not to increase the definition per unit area but it is rather that the visual field percentage contained by the image should be increased. The proposal about all DirecTV HDTV was first submitted by General Instrument Corporation on May 31, 1990
By December 1990 ATRC also launched the same followed by Zenith and AT&T and the MIT. At present Japan is the only country which broadcasts DirecTV HDTV services to the viewers. The number of converters and receivers sold to the customers has reached to 100,000 and 30,000 respectively. The possibility of starting a digital satellite HDTV service in Japan has been eliminated by the establishment of the analog broadcast service, DirecTV HDTV. Right now, many stations do not broadcast HDTV program.
Slowly, the current analog TV can be either replaced or a new set-top box can be purchased for converting the digital signal. While purchasing any TV receivers we should first ensure that the new receiver has all the input jacks that match the connectors on the VCR, cable boxed DVD player etc.
We should always go in for a composite, S-video and component video as a minimum set of analog jacks so we can use our existing analog equipment with a new set.