Other
Frequently Asked Questions about KQED TV's Digital Conversion
What is digital television (DTV)?
The analog picture viewers currently receive is based on an analog transmission system (NTSC)
which is more than 50 years old, and relies on a system of varying voltages to transmit a
television picture. In December 1996 the Federal Communications Commission approved the US standard
for a new era of television - "digital television (DTV)," a general term covering any kind of
digital broadcasting. In a digital system, images and sound are processed using the same digital code
found in computers: converting each element in a complete video picture to a binary code composed of
1s and 0s. The result is a picture with much sharper detail and better color than the analog standards
in current use.
The digital revolution not only dramatically improves the quality of the television picture,
but also makes possible the over-the-air delivery of several simultaneous services to viewers.
These include the three main services of high definition television,
multicasting in standard definition television and data transmission.
Digital television allows stations to broadcast programs in much higher resolution or clarity than
standard analog television. This is called high definition television or HDTV. Viewers at home are able
to receive high-quality, crystal-clear pictures. These visually stunning pictures, with more than twice
the resolution and clarity of standard television, are displayed in a wide screen format with a 16:9
width to height ratio compared to analog's 4:3, or almost square format. And because HDTV is digital,
audiences have the benefit of six-channel CD-quality "surround sound." In other words, viewers are able
to enjoy a true home theater experience. HDTV normally provides 720 or 1080 lines of resolution (depending
on format) vs. 480 lines on standard definition.
This term refers to lower resolution digital broadcasts of about 480 lines of resolution.
New digital TVs are able to receive both HDTV and SDTV broadcasts. SDTV is clearer than analog TV.
Although not as good as HDTV, multiple SD signals can be transmitted in the same bandwidth as one HD signal.
When
not transmitting in HDTV, broadcasters will be able
to transmit four or more channels of SDTV programming
simultaneously. This is called multicasting. Although
SDTV will not match HDTV in quality, it will still
offer a higher quality picture than NTSC analog versions.
When transmitting in HDTV, fewer SD channels will can be multicast at the same time.
What is datacasting: enhanced and interactive DTV?
Digital broadcasting will offer an entirely new form of programming: enhanced digital television - the fusion of video, audio, images and text. For the first time, producers will be able to combine the storytelling power of video and film with the enormous data capacity of a digital television signal.
Viewers will be able to simultaneously watch an enhanced TV production and, in the background, receive hundreds of megabytes of additional video, audio, text and images related to the program. This information can include recipes from your favorite cooking show, lesson plans for classroom teachers, biographies of actors, program transcripts and resources for additional information. Imagine your favorite PBS documentary accompanied by a companion CD-ROM, but with the content stored directly on your computer or in the memory of your digital set-top box
Until February 17, 2009, stations will be transmitting programs in both analog and digital.
Today's TVs will continue to display analog transmissions (or dtv signals with appropriate receivers
and antennas) during that transition period. The FCC has mandated beginning February 18, 2009, all
TV broadcasting will be digital only. Viewers will still be able
to enjoy VHS tapes, DVD discs, and cable or satellite TV on current sets. Viewers who use indoor or outdoor
antennas to get their signal for their analog sets will need to purchase a digital converter box for your analog TV
in order to get any broadcast signals at all. However, although the digital converter box will allow
you to receive a picture, it won't display the quality of HD. (more info about the
DTV conversion.)
To receive KQED DT9 over the air, viewers must have
a good quality antenna attached to the digital receiver.
Depending upon your sight-line to Sutro Tower, multi-path
issues, and the quality of your current antenna,
it is possible that your current antenna (indoor
or rooftop) could receive digital station signals.
Or you may need a new one of better quality. It's
important to remember that with the new digital
system, the picture quality will always be sharp;
there is no ghosting or degration of signal with
DTV - you will receive a studio quality picture
or nothing at all.
What is the viewing area for the new digital channels?
The KQED digital signal
extends nearly 65 miles in all directions from
our transmitter site on Sutro Tower, but it is
terrain-sensitive. Comcast Cable will extend the
coverage area as the services becomes available.
KQED HD is now available on Comcast Cable Channel
709. For more information on this service, visit our
DTV, Cable and Satellite Info page.
Why does digital technology change the shape of the picture? What's with those black stripes on my analog TV? Why do we end up with Letterbox format?
The
original 4:3 picture ratio was established to cloesely
match the ratio used in film at the time. The new
16:9 ratio closely matches motion picture standards
today. The letterbox format which is showing up
on analog sets more and more allows viewers to see
the entire production in 16:9 ratio, without losing
nearly a third of the movie to cropping or pan & scan
techniques. In other words, you're seeing the show
as the producer/director created it, not reformatted
to fit the nearly square 4:3 ratio of analog sets.
(for more details, check out Robert Cringely's A
Different Aspect web pages.)
Will you be able to watch your existing VHS or DVD
collection (in a 4:3 ratio) on a new digital TV?
Most digital sets have an analog input that will
allow you to hook up your existing DVD or VHS player.
However, the picture quality will not be any better
than that of a high quality standard television
monitor.
KQED
is required by the Federal Communcations Act of
1996, an unfunded federal mandate, to convert to
digital broadcasting. Digital technology condenses
broadcast signals to make room on the spectrum for
cellular phones, paging, and other systems. By auctioning
that space, the government hopes to add billions
to the US Treasury and reduce the national debt.
The FCC mandated that all public television
stations in the country begin digital transmission by May 2003.
Beyond the federal mandates and deadlines, KQED's DTV capability
will allow the station to digitally broadcast over a variety of formats,
including multicasting on up to five channels, broadcasting with enhanced
or interactive television and, of course, airing programs in HDTV. Our ability to multicast
a variety of programs at the same time will allow viewers a greater flexibility in making
their television choices.
That's
a question for your favorite home entertainment
retailer. Prices are in the $1000-$8000 range,
but can cost more. As with all new electronic devices,
prices are expected to come down over time. To give
some perspective, The first color televisions sold
for about $700, which in today's dollars translates
to about $7000.
A lot less - anything from a $60 to $200 - but you get the
features you pay for. Although the digital converter box will allow you to receive a picture,
it won't allow access to high-definition or interactive programming, data, or other digital programming
services.
How can I keep up-to-date with KQED TV's conversion, and HDTV programming plans?
If you would like to receive twice-monthly email updates about upcoming programs, along with occasional
alerts regarding KQED's continuing conversion, visit our
Newsletters Subscriptions page, and sign up for HDTV Alerts.
What is the difference between DT-9.1, and DT-9.2 & 9.3?
KQED
is multicasting, currently using Digital channels 9.1 through 9.3.
Channel 9.1 is a simulcast of flagship channel Analog TV9's schedule,
using HD and widescreen versions of programs whenever available.
Channels 9.2 and 9.3 offer Standard Definition programs.
Since May 2000, KQED has been broadcasting a digital signal on its assigned channel, DT30.
On most digital receivers, you can still tune to DT30, but you will probably see the channels labeled
as 9.1, 9.2, etc., on your screen. Or you can tune directly to 9.1, 9.2, etc. since we use a "virtual ID"
system to identify our digital channels as part of Channel 9. Because systems vary, please refer
to your owner's manual for more information on channel navigation.
These digital program services are transitional as KQED builds a multicast service
that will offer up to four simultaneous digital channels. During this transition, we may change
the program mix on the digital transmitter to do testing, transmit data or broadcast other programs.
Viewers who watch KQED channel 9 on standard analog sets will not experience any change in their service until the federally mandated shut-off date of 2/17/09.
The minimum requirement for getting some benefit from
digital broadcast is a digital receiver with a good
antenna attached to receive KQED DT9 over the air. Or
viewers can subscribe to one of Comcast Cable's digital
packages. A digital television is not an initial requirement.
To receive KQED DT9 over the air, a digital receiver
will output a video signal (S-video, composite video,
or even RF) to a conventional TV set. Many viewers would
still benefit from a clearer signal (no ghosting), better
colors and sound, and no other annoying interference.
The next step would then be to add a better monitor.
Many people may already have a computer monitor they
could use at first, to see the quality difference. The
final step would then be to add a digital television
set (monitor), in order to take full advantage of all
services offered, such as high-definition or interactive
programming, data, or other digital programming services.
Viewers can also receive the KQED DT-9 signal on a personal
computer by installing a PC-DTV card and attaching an
antenna to the PC. The PC-DTV card turns your computer
into a television that can receive over the air signals
or be connected to cable.
Information about programs and material scheduled to
be broadcast on KQED's HD/Widescreen Channel is available
by visiting KQED's
DT-9.1 Schedule
KQED has put together a glossary
of terms you're likely to see and hear over the
upcoming months, and a list
of resources for more information about DTV.
find answers to...
schedule changes
digital tv tech FAQ
requirements
about KQED
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