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Old December 22nd 07, 09:49 AM posted to rec.radio.shortwave
RHF RHF is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Future of SW Broadcasting?

On Dec 21, 8:34*pm, (Jim Haynes) wrote:
I keep reading here things like shortwave broadcasting is going away.
But the new QST has a report on an international radio conference
where they say the broadcasters are trying to get more frequencies
in the HF region. *So what is going on?


JH,

Digital Radio Mondiale (DRM) eats up the High Frequency
{Shortwave} Radio Spectrum.
http://en.wikipedia.org/wiki/Digital_Radio_Mondiale

A Listener's Guide to Digital AM (DRM)
http://www.radionetherlands.nl/featu...siers/drm.html

Where Shortwave Analog Broadcasters could use 10 kHz
Channel Spacing with the old AM Transmission Mode.

DRM Shortwave 'Digital' Broadcasters need to use 25 kHz
of Channel Spacing for Standard DRM; and 50 kHz for Wide
DRM of Channel Spacing with the DRM Transmission Mode.

* DRM Digital Signal 'centered' on 13790 kHz with
http://shortwaveradio.org/drm_13_Af_010511_2100.jpg
AM Analog Signals on 13770, 13800, and 13810 kHz
http://radio.org.pl/~sp2mkt/TS570/DRM/shape.jpg

* One of the 'Killer Features' of DRM is 18 kHz Double
Channel : Kills everything within 25 kHz of the Center
Frequency ~ 50 kHz.
http://www.drm.org/system/technicalaspect.php

* Only a DRM Radio Station Broadcasting in Mode 'A'
or Mode 'B' using 18/20 kHz of Spectrum can deliver
'FM Quality' Audio.
http://www.drmradio.co.uk/html/drm_bandplan.html
* The UK's AM/MW Band 'X' Band may be extented from
1642 kHz to 1782 kHz for DRM.

~ RHF