"Byung Myung Sying" wrote in message
...
I wrote

Shortwave DX'ers have always had to struggle agains QRN from the
USSR's "woodpecker", the RTTY news services etc. DRM is no better
and no worse than any of these noises.


Frank replied:
DRM noise may be no worse than other sources of interference were, but
there
is no longer any justification for such interference. There's plenty of
open spectrum now. -

I reply to Frank:
No the case is absolutely the opposite. Spectrum space is much more
costly and less available than it was.


Absolutely the opposite? Please tell me which of these points are wrong:

1) The great transmitting stations with huge antenna farms which moved
thousands of messages across continents and oceans are now almost entirely
gone.

2) The news services are largely off shortwave.

3)Most military and diplomatic traffic is now carried off shortwave.

4) Shortwave broadcasters are reducing the number of hours they broadcast.

5) Several international broadcasters have dropped shortwave entirely.

I hear much less activity on shortwave than I did back in the 70s,
especially outside the SW broadcast and amateur bands. I'll admit I don't
keep detailed records of such things, but I really do think I'm correct.

Please detail just how SW spectrum has become less available and more costly
than it was.

The DRM'ers are using
absolutely legal, internationally allocated frequencies for their
transmissions. There is no legal or technical reason for them to
change their frequencies.


I never suggested the DRMers were lawbreakers. Not that that would much of
a point, because SW law isn't often enforced on an international level.

There is a good technical reason why DRM broadcasts should be segregated.
DRM does cause more interference, despite using the same channel width as
what's allocated to a standard broadcaster. DRM sounds like it has an even
distribution of energy across it's bandwidth, which means it has much more
energy 1 kHz or so off the carrier than a standard AM signal.



Frank wrote:

Satellite radio is an even better solution from the reliability and real
estate point of view.

DRM is an attempt to compete with satellite radio. -snip-

I reply:

Granted that satellite radio is a much better form of shortwave
broadcast transmission -- that's what I said in my last post! Read it
again: "It is questionable as to whether DRM will ever become viable
due to shortwave's unpredictablility and the high cost of real estate
necessary for broadcast of shortwave signals". I will also add that
the environmental impact from a 200 kW shortwave broadcast transmitter
is much greater than that of a satellite uplinker.

As to your argument that SWL'ers enjoy the unpredictability of
shortwave, I've been at it for many years and have logged and verified
thousands of commercial, utility, and ham contacts. DRM DX'ing is
another interesting challenge to the hobbyist.

Great. Let the DRM broadcasters play with of the frequencies RCA and AT&T
aren't using anymore.

Frank Dresser