Since HD radio is becoming more and more popular, I thought I would post
some FAQ's about it.
Q: What is HD Radio?
A: The term "HD Radio" is iBiquity Digital Corporation's trademarked name
for their digital audio broadcasting technology, which has become the IBOC
standard
adopted for the United States.
Q: What's IBOC?
A: IBOC - In Band On Channel - derives its name from the kind of digital
signal being broadcast. IBOC signals use the same AM and FM bandwidth as a
station's
analog signal ("in band"). The digital information is contained within the
station's signal ("on channel").
Q: Is HD Radio technology the same as HDTV?
A: Only in the sense that they're both digital signals. Television's move to
HDTV was mandated by the federal government. On the other hand, radio
stations
are voluntarily adding HD Radio technology to their regular broadcasts.
Stations will continue using the same AM and FM frequencies they do now.
Q: What does "HD" stand for?
A: Originally, the initials stood for "hybrid-digital," because the digital
signals were carried with the analog wave. According to iBiquity Digital
Corporation,
that's been changed, and the letters "HD" now don't stand for anything. Some
articles and news stories have erroneously assumed that "HD" stands for
"high
definition," which has contributed to the confusion between HD Radio
technology and high-definition TV.
Q: My favorite station says they're now broadcasting in HD Radio, but I
don't hear a difference. What gives?
A: Many radio stations promote their HD Radio capability in their analog
broadcasts. This sometimes leads to a little confusion, as the listener can
assume
that "now broadcasting in HD Radio" refers to a signal upgrade that only
needs to happen at the station's end. It's not.
Unless you have an HD Radio tuner, you won't receive the digital HD Radio
signals. So when you hear a station talking about HD Radio on your old
receiver
- and you don't hear a difference in sound quality - you're probably still
just receiving the analog signal. Only after you've purchased an HD Radio
tuner
can you hear the difference.
Q: How is HD Radio different than current FM and AM radio?
A: Because they're digital, HD Radio signals aren't subject to atmospheric
interference the way current FM and AM signals are. Background crackle and
hiss
are eliminated. The effect is similar to the difference between CDs and
vinyl records. The digital CD signal is free of the surface noise that's
always
present on LP playback.
Q: How can I find out if my local station is broadcasting digitally?
A: As stations add HD Radio capability to their service, they generally
publicize the fact. iBiquity Digital also maintains a site that lists which
stations
are broadcasting with HD Radio signals. Go to
hd-radio.com
to find stations broadcasting in HD Radio in your area.
Q: My radio isn't compatible with HD Radio broadcasts. Will it become
obsolete?
A: Partially. Stations broadcasting with HD Radio technology will continue
to simulcast their AM or FM analog signals, so you'll be able to enjoy the
same
stations as before. Without an HD Radio tuner, though, you'll miss out on
the digital-only multicast channels some stations now offer.
Q: What is multicasting?
A: An HD Radio signal can be subdivided to send out two or more different
kinds of programming simultaneously. When a station does this, it is
multicasting.
Q: What is HD2?
A: HD2 is the term multicasting stations are using for their secondary
digital-only channel. Some stations are using this second channel to offer
more
specialized programming, such as Latin Hits, Classical Opera, and
Electronica.
Q: Can all HD Radio tuners get these extra channels?
A: Multicasting was developed after the first generation of HD Radio tuners
hit the market. While all HD Radio tuners will pick up the station's primary
digital channel, only radios that are designated multicast-capable will be
able to pick up HD2 and any additional subchannels. Multicasting capability
has since become a standard feature on HD Radio tuners. At this point,
virtually all HD Radio tuners on the market can receive multicast channels.
Q: Satellite radio requires a monthly subscription fee for their digital
broadcasts. What do HD Radio broadcasts cost?
A: Like current FM and AM radio, HD Radio broadcasts are free to the public.
Your only expense is the purchase of an HD Radio tuner.
Q: Is the coverage area of my station's HD Radio signal identical to that of
their current signal?
A: Currently, the FCC requires that stations' digital transmitters operate
at lower power levels than their older analog counterparts. Because terrain
obstacles affect analog and digital signals in slightly different ways,
there's no sure-fire way to predict reception. For many stations, though,
the coverage
area for HD Radio seems to be about 60% of the analog coverage area. The FCC
is expected to raise the limits for digital broadcast power in the near
future.
This should make the HD Radio coverage area for a station similar to - but
not exactly the same as - its analog coverage area.
Q: What happens if I lose the HD Radio signal?
A: If your HD Radio tuner loses the station's digital signal, it will
automatically switch over to the analog signal broadcast at the same
frequency. There
may be a slight break in the sound when this happens. When the tuner is back
in range of your station's HD Radio signal, it will automatically go back
to the digital broadcast.
Q: I see a lot of car radios use the term "HD Radio ready." What does that
mean?
A: An HD Radio ready car radio - or "head unit" - can play HD Radio signals,
but requires connection to a separate HD Radio tuner. If the radio is a
factory
stereo, you'll have to get the tuner from the dealer. If you have a
brand-name stereo, we probably have the add-on tuner you need.
Q: Can I only hear HD Radio in the car?
A: No. Several manufacturers offer stand-alone tabletop radios that have
built-in HD Radio tuners. There are also a few home theater and stereo
receivers
with HD Radio tuners available as well. And the Zune HD digital player has
an HD Radio tuner built in for portable listening.
Q: What is "tagging"?
A: "Tagging" is short for either iTunesR Tagging (if your using an iPod), or
Song Tagging (if you're using a Zune HD). Tagging is a process that lets you
select the song you're listening to on an HD Radio station and create a
reminder on your portable player to purchase it at a later time. To take
advantage
of this feature, you need two things: a compatible iPod or Zune HD, and a
local radio station that's broadcasting an HD Radio signal with tagging
enabled.
As you're listening to the HD Radio signal, press the "Tag" button when you
hear a song you'd like to purchase. This saves the song information (but not
the song itself) to your player's memory. When you synch your player to your
computer, your tagged selections will appear as a list in either the iTunes
Store (if you're using an iPod) or the Zune Music Store (if you're using a
Zune HD), giving you the option of purchasing them through the store.
____________________________________________________
Denny Huff - President
Missouri Council of the Blind
Toll Free: (888) 362-1383
Cell: (636) 262-1383
MCB Phonecast: (816) 298-8969
<mailto:[email protected]> [email protected]
<http://www.MoBlind.Org> WWW.MoBlind.Org
_________________________________________________
The purpose of Missouri Council of the Blind shall be to promote the general
well-being of our members and legally blind people in Missouri, and to
support or participate in other programs promoting the best interests of
legally blind people everywhere.
_______________________________________________
ATI (Adaptive Technology Inc.)
A special interest affiliate of the Missouri Council of the Blind
http://moblind.org/membership/affiliates/adaptive_technology
