On Sun, 25 Jan 2004 21:20:31 GMT, Telamon
wrote:
In article ,
(Sidchase3) wrote:
Has anybody built or bought a DRM capable receiver? I printed out a
schedule of broadcastng times from the DRM website. It appears that
there are test transmissions going on from participating broadcasters
a good part of the day. One station transmits for an hour or two and
then passes off to another.
Has anyone heard these broadcasts? How was the clarity? As I
mentioned in Future of shortwave, I think there is tremendous
potential for digital shortwave particularly concerning the
transmission of text. The ability to interface these receivers with a
computer (PC, laptop, palm) coupled with the relatively high coverage
to cost ratio would enable a greater variety of thought (political,
social) from marginalized groups to the reach the public.
As far as the FCC banning domestic broadcasts, the law could be
challenged in court--I admit I don't know what the cost would be. But
more importantly, I think the ban needs to be challenged in the
court of public of opinion. Given the ridiculous situation today in
which businesses can own multiple stations in one locality and
enormous corporations control all the programming for those stations
the FCC's rationale for the ban falls flat on its face. Ironically,
domestic shortwave would represent the kind of programming diversity
that the FCC claims it wants to promote.
I strongly disagree that DRM in its current form will create over all
improved radio reception than analog. DRM reception will be different
and could be judged "better" at times but over all different conditions
and situations reception will be no better off than analog.
I believe that DRM can never be mertely "no better than analog".
Provided you can receive the signal in the first place, you can't
possibly get the usual background noise, fading, and limited bandwidth
as you get with analog, because you re receiving an MP3 compressed
digital signal, which is practically FM broadcast quality.
On the other hand, if you can't receive the signal with the required
threshold signal-to-noise ratio, you will hear nothing. Not even
noise, just pure silence.
Besides being no better than the current analog regime DRM brings
several new negatives along with it like some of the codexes are still
proprietary. The radios will consume more power and cost more money.
If the codec is a proprietary HCMOS chip, the extra 20mA or so won't
make much difference to the battery life. With software-based PC
receivers like the Winradio G303, this point does not apply.
The cost issue will depend on economy of scale. If there are millions
of users (as DRM obviously must anticipate), the chip will cost just a
few dollars, and may also integrate other existing receiver functions,
for example a conventional AM/FM demodulator, so it won't add
significantly to the cost of the radio.
Other negatives are the ability to control where broadcasts are heard
and by whom. What is going to stop a consortium of radio manufactures
and broadcasters if the broadcasters want certain broadcasts to be
heard only on certain continents similar to what is done with DVD's as
an example of potential abuse of a digital system?
This is potentially true, but it would be much harder to police than
with DVD (where the so-called "zoning" was a failure anyway and in
most countries you now get multi-zone DVD players as a matter of
course, no questions asked).
Whether anyone likes it or not the change to DRM means that shortwave
will no longer be a world wide medium.
The DRM consorcium must make it a world-wide medium in order for the
standard to succeed in the first place.
George