In article
,
gallant17 wrote:

On Jun 6, 7:35*am, "David Eduardo" wrote:
"Rfburns" wrote in message

...
A friend let me borrow his Sony XDR-S3HD radio before he sells it on
eBay to try and recoup some of his money. *Trying it out I kept
wondering * what¹s so compelling about this? *I could detect virtually
no difference in audio quality between FM analog and FM ³HD².

On a larger radio, there is a definite improvement in audio, but one of the
big advantages is the near total absence of multipath in vehicles in motion.

*What was even more irritating was that the analog and
digital signals were out of sync by about 5 seconds. *So much for a
smooth transition. *No CD Quality here boys.

The delay is supposed to be synchronized by the station. Obviously, the
station did not do this right, which is not HD's fault. All stations I have
heard transition seamlessly.

The real shocker was how power hungry the radio must be * and this is
just a tabletop clock radio * nothing fancy. *It comes with a MASSIVE
external power transformer ³brick² that you could use as an anchor for
a boat.

The available second generation receivers, overall, suck.

"Renowned Cambridge SoundWorks HD Radio Designer Explains HD Radio"

"HD Radio broadcasts require a consistent, stronger signal than analog
broadcasts... Below the minimum required signal le vel, the HD Radio
program switches back to the analog signal... There is a limit to how
far you can be from a transmitter and still receive an HD Radio
transmission. For flat land with no obstructions, this limit could be
as far away as 20-25 miles. For hilly terrain, the limit may drop to
10-15 miles. For the strongest signal within 20 miles of a radio
transmitter, the user should position the provided 30 inch dipole
antenna either horizontally or vertically along a wall or window."

http://www.hdradio.com/the_buzz.php?thebuzz=87

Do you understand why this is? It is because no thought was applied to
quality of service of the radio signal. This is a glaring omission in
the IBOC specification.

"IBOC TECHNOLOGY: An Assessment of Technical & Operational Issues in
the Canadian FM Radio Environment"

"For a variety of reasons relating to the time requirements for
digital signal processing, it takes 8-10 seconds for the digital audio
signals to be heard when an HD Radio receiver is first tuned to a
transmission. Likewise, it can take equally long to restore digital
quality when the signal fails and then returns again. A secondary
consequence of this processing delay is that programming fed to the
analog FM transmitter must be delayed by 8-10 seconds whenever the
blending feature is being utilized. This ensures that content is not
lost when the receiver switches back to analog mode during a digital
signal failure. Stations using this technology may need to implement
certain internal operational changes to accommodate the fact that off-
air listeners will experience delays of up to 10 seconds with both the
analog and digital versions of their programming. Since no analog
program version exists for ancillary HD2 or HD3 programming, listeners
experiencing digital failures must simply tolerate audio outages until
the signal restores itself."

http://www.cab-acr.ca/english/radio/...port_final.pdf

What a piece of crap system.

"HD Radio set to botch its first impression"

"It is patently stupid to tack on HD stations to existing analog
frequences (as in 98.5-1, 98.5-2, 98.5-3) and then put three different
things on those frequencies... Furthermore, the names are so
incredibly clunky, moving newfangled digital radio strongly in the
direction of even clunkier HAM radio. It's a confusing mass of digits,
decimals, and dashes."

http://www.hear2.com/2005/08/hd_radio_set_to.html


The HD signals are even more prone to dropouts in moving vehicles, if
even the signals can be picked up. If the signals are synced, then
there is a 5 to 10 second delay for acquiring the signals, as they are
constantly rebuffered.. Navigating the HD dial is a nightmare. This
system simply doesn't work, and is not applicable for real-world
applications. Consumers will no put up with this defective system.

IBOC is a piece of crap engineering and that management would put such a
miserable system on the air is almost beyond belief.

--
Telamon
Ventura, California