Very well said.
On 01-Jan-15 2:21 AM, Markus
Vester wrote:
As announced before,
the German longwave broadcast transmissions on 153 and 207
kHz (Deutschlandfunk) and 177 kHz (Deutschlandradio) will be terminated with
the New Year 2015. Presumably mediumwave AM transmissions will follow
one year later. It has been claimed that the continuation would be too
costly, considering the relatively small number of AM
listeners.
Along with others, I think that this is a sad
landmark in radio history, because
- AM radio is simple and intuitive. The
concepts of AM transmission and reception are easy to conceive,
even by a child. And it's motivating to play with it. In a few years, the
kids can still build a diode receiver, but listening to the small
surrogate oscillator Daddy has hidden behind the sofa will surely not be the
same thing!
Then try to explain digital audio broadcasting
to your grandson, all the way from end-to-end (microphone to speaker. I even
have strong doubts that there is a single expert person now who
understands the whole chain. Every engineer is supposed to be working on the
details of a small subpart, knows little more than he "needs to know",
and communication is done by formal processes and requirement
specifications. Of course this is a general trend in industry, but I
don't think it is very desirable.
- AM is linear. Listening to 153 kHz in the evening hours, faint Algerian music
can be heard in the background. When I was young I was fascinated by those
distant sounds, and it probably contributed strongly to my later interest in
"DX". You can actually hear that the radio waves have come a long way,
experience selective fading, and solar effects, or subtle
ionospheric effects like Luxembourg crossmodulation. Modern digital
radio considers all this undesirable interference - what you get
is either perfect mp3 stereo, or nothing at all.
- AM is a historic legacy. Especially on
longwave, each transmitter and antenna coupler is a unique
installation, and the antennas are impressive monuments. SAQ is a good
example: While it's no longer needed for transatlantic
communication, it's still being kept alive as
an educative and fascinating world heritage. Why not keep at least
one large LF broadcast transmitter?
- LF and MF radio is efficient. The
half-megawatt Donebach transmitter probably consumes a million Euros worth
of energy per year, and in addition, there is antenna and
transmitter maintenance to be paid for. But it provides gapless service
across many million square kilometers. Similar coverage with DAB will
probably require a thousand or more digital transmitters, which in total may
well consume a higher amount of power and secondary costs. One
difficulty about keeping LF transmitters alive may actually be there are so
few of them - as most engineers seem to be working on software and
silicon chip-level hardware, it may become hard to make spare parts and
find experienced service people for high-voltage RF in the
future.
- Radio helps to protect against spectrum
pollution. Members of the LF group are only too aware of the inflation of
inadequately filtered SMPS power supplies, "dirty" ADSL and PLC
communication over unshielded copper lines, and upcoming
threats like inductive e-car charging devices. Currently there
are still EMC regulations in place which at least provide
some limit on radiated and conducted interference above 150 kHz. But
when there are no more AM broadcast listeners, why should anyone invest
effort to protect that part of spectrum against local interference? The
situation for those few crazy LF enthusiasts who enjoy digging down to the
noise floor may soon become comparable to that of backyard astronomers in an
urban environment - ie plain frustrating.
End of rant...
Anyway, all the best for the new
year,
Markus (DF6NM)
No virus found in this
message.
Checked by AVG - www.avg.com
Version: 2015.0.5577 / Virus
Database: 4257/8841 - Release Date: 12/30/14
